Typical side-effects of antidepressants include dry mouth, weight gain, and lack of sex drive. Most types of antidepressants are typically safe to take, but may cause increased thoughts of suicide when taken by children, adolescents, and young adults. A discontinuation syndrome can occur after stopping any antidepressant. The risk is greater among those who have taken the medication for longer and when the medication in question has a short half-life. The problem usually begins within three days and may last for several months. Methods of prevention include gradually decreasing the dose among those who wish to stop, though it is possible for symptoms to occur with tapering.
The most important classes of antidepressants are:
One theory regarding the cause of depression is that it is characterized by an overactive hypothalamic–pituitary–adrenal axis (HPA axis) that resembles the neuro-endocrine response to stress. HPA-axis abnormalities participate in the development of depressive symptoms, and antidepressants may serve to regulate HPA-axis function.
The medical community has long debated the effectiveness of antidepressants, concentrating on whether one can attribute observed results in patients to the placebo effect.
The UK National Institute for Health and Care Excellence (NICE) 2009 guidelines indicate that antidepressants should not be routinely used for the initial treatment of mild depression, because the risk-benefit ratio is poor. The guidelines recommended that antidepressant treatment be considered for:
People with a history of moderate or severe depression,
Those with mild depression that has been present for a long period,
As a second-line treatment for mild depression that persists after other interventions,
As a first-line treatment for moderate or severe depression.
The guidelines further note that antidepressant treatment should be used in combination with psychosocial interventions in most cases, should be continued for at least six months to reduce the risk of relapse, and that SSRIs are typically better tolerated than other antidepressants.
American Psychiatric Association treatment guidelines recommend that initial treatment should be individually tailored based on factors that include severity of symptoms, co-existing disorders, prior treatment experience, and patient preference. Options may include pharmacotherapy, psychotherapy, electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS) or light therapy. They recommended antidepressant medication as an initial treatment choice in people with mild, moderate, or severe major depression, that should be given to all patients with severe depression unless ECT is planned.
Conflicting results have arisen from studies analyzing the efficacy of antidepressants by comparisons to placebo in people with acute mild to moderate depression. Stronger evidence supports the usefulness of antidepressants in the treatment of depression that is chronic (dysthymia) or severe.
A 2018 meta-analysis of trials found that in adults with major depressive disorder antidepressants were more efficacious than placebo 
Effect sizes measured at 8-weeks after treatment onset were modest with a summary standard mean difference of 0.3.
A 2018 meta-analysis of trials found that antidepressants showed little or no effect for treating depression in dementia.
A 2017 meta analysis comparing the efficacy of SSRIs against placebo found the mean reduction in Hamilton Depression Rating Scale (HDRS) to be -1.94 points over 49 studies. This was statistically significant, but failed to meet the clinical significance threshold, predefined according to the National Institute for Health and Care Excellence recommended standard mean difference of 0.5, equivalent to a 3-point reduction in HDRS. A high risk of bias was found, which could possibly explain the statistically significant effect of SSRI, and the authors concluded that the frequency of adverse events outweighed the small clinical improvements.
A 2015 systematic review of add-on therapies for treatment-resistant depression concluded that quetiapine and aripiprazole have the strongest evidence-base supporting their efficacy, but they are associated with additional treatment-related side effects when used as an add-on therapy.
In 2014 the U.S. FDA published a systematic review of all antidepressant maintenance trials submitted to the agency between 1985 and 2012. The authors concluded that maintenance treatment reduced the risk of relapse by 52% compared to placebo, and that this effect was primarily due to recurrent depression in the placebo group rather than a drug withdrawal effect.
A 2012 meta-analysis found that fluoxetine and venlafaxine were effective for major depression in all age groups. The authors also found no evidence of a relationship between baseline severity of depression and degree of benefit of antidepressants over placebo.
A review published in 2012 found a negative correlation between study year and efficacy of antidepressants as measured by response rate. The change in response rate was largely driven by increase in placebo response. However the authors still concluded that antidepressants were effective in treating depression. The authors found that TCAs were the most effective drug, followed by SNRIs, MAOIs, SSRIs and atypical antidepressants.
The efficacy of paroxetine (Paxil) and imipramine was observed in a 2010 meta analysis to be dependent upon the baseline severity, as measured by the HDRS. Antidepressants in patients with a score less than 23 (indicating mild to moderate depression) demonstrated a small benefit over placebo. However, antidepressants in those with a score >25 exhibited an advantage over placebo that cross the NICE threshold for clinical significance.
A review commissioned by the National Institute for Health and Care Excellence that published in 2009 concluded that there is strong evidence that SSRIs have greater efficacy than placebo on achieving a 50% reduction in depression scores in moderate and severe major depression, and that there is some evidence for a similar effect in mild depression. The treatment guidelines developed in conjunction with this review suggest that antidepressants should be considered in patients with moderate to severe depression and those with mild depression that is persistent or resistant to other treatment modalities.
In a 2008 publication, Irving Kirsch and Thomas Moore concluded that the overall effect of new-generation antidepressant medication is below recommended criteria for clinical significance. This updated work they had first published in 2002 in which they stated that the evidence is most consistent a role as active placebos.
A 2004 review concluded that antidepressant studies that failed to support efficacy claims were dramatically less likely to be published than those that did support favorable efficacy claims. Similar results were obtained for a study of publication of clinical trials of antidepressants in children. A 2015 investigation of meta-analyses of antidepressant studies found that 79% of them had "sponsorship or authors who were (pharmaceutical) industry employees and/or had conflicts of interest".
A study published in the Journal of the American Medical Association (JAMA) in 2002 demonstrated that the magnitude of the placebo effect in clinical trials of depression have been growing over time, while the effect size of tested drugs has remained relatively constant. The authors suggest that one possible explanation for the growing placebo effect in clinical trials is the inclusion of larger number of participants with shorter term, mild, or spontaneously remitting depression as a result of decreasing stigma associated with antidepressant use. Placebo response rates in clinical trials of complementary and alternative (CAM) therapies are significantly lower than those in clinical trials of traditional antidepressants.
The STAR*D Trial
The largest and most expensive study conducted to date, on the effectiveness of pharmacological treatment for depression, was commissioned by the National Institute of Mental Health. The study was dubbed "The Sequenced Treatment Alternatives to Relieve Depression" (STAR*D) Study. The results are summarized here.
Participants in the trial were recruited when they sought medical care at general medical or psychiatric clinics. No advertising was used to recruit subjects in order to maximize the generalizability of the study results. Participants were required to have a minimum score of 14 points on the Hamilton Depression Scale (HAM-D17) in order to be enrolled in the trial. Generally accepted cutoffs are 7–17 points for mild depression, 18–24 points for moderate depression, and ≥ 24 for severe depression. The average participant baseline HAM-D17 score was 22. The pre-specified primary endpoint of this trial was remission as determined by the HAM-D score, with all patients with missing scores rated as non-responders. In the aftermath of the trial, the investigators have presented the results mainly using the secondary endpoint of remission according to the QIDS-SR16 Score, which tend to be somewhat higher.
After the first course of treatment, 27.5% of the 2,876 participants reached remission with a HAM-D score of 7 or less and 33% achieved remission according to the QIDS-SR scale. The response rate according to the QIDS-SR16 score was 47%. Twenty-six percent dropped out.
After the second course of treatment, 21 to 30% of the remaining 1,439 participants remitted. Switching medications can achieve remission in about 25% of patients.
After the third course of treatment, 17.8% of the remaining 310 participants remitted.
After the fourth and last course of treatment, 10.1% of the remaining 109 participants remitted.
Relapse within 12 months was 33% in those who achieved remission in the first stage, and 42% to 50% in those achieving remission in later stages. Relapse was higher in those who responded to medication but did not achieve remission (59–83%) than in those who achieved remission.
There were no statistical or meaningful clinical differences in remission rates, response rates, or times to remission or response among any of the medications compared in this study. These included bupropion sustained release, bupropion, citalopram, lithium, mirtazapine, nortriptyline, sertraline, triiodothyronine, tranylcypromine, and venlafaxine extended release.[medical citation needed]
A 2008 review of randomized controlled trials concluded that symptomatic improvement with SSRIs was greatest by the end of the first week of use, but that some improvement continued for at least 6 weeks.
Limitations and strategies
Between 30% and 50% of individuals treated with a given antidepressant do not show a response. In clinical studies, approximately one-third of patients achieve a full remission, one-third experience a response and one-third are nonresponders. Partial remission is characterized by the presence of poorly defined residual symptoms. These symptoms typically include depressed mood, psychic anxiety, sleep disturbance, fatigue and diminished interest or pleasure. It is currently unclear which factors predict partial remission. However, it is clear that residual symptoms are powerful predictors of relapse, with relapse rates 3–6 times higher in patients with residual symptoms than in those who experience full remission. In addition, antidepressant drugs tend to lose efficacy over the course of treatment. According to data from the Centers for Disease Control and Prevention, less than one-third of Americans taking one antidepressant medication have seen a mental health professional in the previous year. A number of strategies are used in clinical practice to try to overcome these limits and variations. They include switching medication, augmentation, and combination.
"Trial and error" switching
The American Psychiatric Association 2000 Practice Guideline advises that where no response is achieved following six to eight weeks of treatment with an antidepressant, to switch to an antidepressant in the same class, then to a different class of antidepressant.
A 2006 meta-analysis review found wide variation in the findings of prior studies; for patients who had failed to respond to an SSRI antidepressant, between 12% and 86% showed a response to a new drug. However, the more antidepressants an individual had already tried, the less likely they were to benefit from a new antidepressant trial. However, a later meta-analysis found no difference between switching to a new drug and staying on the old medication; although 34% of treatment resistant patients responded when switched to the new drug, 40% responded without being switched.
A combination strategy involves adding another antidepressant, usually from a different class so as to have effect on other mechanisms. Although this may be used in clinical practice, there is little evidence for the relative efficacy or adverse effects of this strategy. Other tests recently conducted include the use of psychostimulants as an augmentation therapy. Several studies have shown the efficacy of combining modafinil to treatment-resistant patients. It has been used to help combat SSRI-associated fatigue.
The therapeutic effects of antidepressants typically do not continue once the course of medication ends. This results in a high rate of relapse. A 2003 meta-analysis of 31 placebo-controlled antidepressant trials, mostly limited to studies covering a period of one year, found that 18% of patients who had responded to an antidepressant relapsed while still taking it, compared to 41% whose antidepressant was switched for a placebo.
A gradual loss of therapeutic benefit occurs in a minority of people during the course of treatment. A strategy involving the use of pharmacotherapy in the treatment of the acute episode, followed by psychotherapy in its residual phase, has been suggested by some studies.
Generalized anxiety disorder
Antidepressants are recommended by the National Institute for Health and Care Excellence (NICE) for the treatment of generalized anxiety disorder (GAD) that has failed to respond to conservative measures such as education and self-help activities. GAD is a common disorder of which the central feature is excessive worry about a number of different events. Key symptoms include excessive anxiety about multiple events and issues, and difficulty controlling worrisome thoughts that persists for at least 6 months.
Antidepressants provide a modest-to-moderate reduction in anxiety in GAD, and are superior to placebo in treating GAD. The efficacy of different antidepressants is similar.
SSRIs are a second-line treatment of adult obsessive–compulsive disorder (OCD) with mild functional impairment and as first-line treatment for those with moderate or severe impairment. In children, SSRIs can be considered as a second-line therapy in those with moderate-to-severe impairment, with close monitoring for psychiatric adverse effects. SSRIs are efficacious in the treatment of OCD; patients treated with SSRIs are about twice as likely to respond to treatment as those treated with placebo. Efficacy has been demonstrated both in short-term treatment trials of 6 to 24 weeks and in discontinuation trials of 28 to 52 weeks duration.
Antidepressants are recommended as an alternative or additional first step to self-help programs in the treatment of bulimia nervosa. SSRIs (fluoxetine in particular) are preferred over other antidepressants due to their acceptability, tolerability, and superior reduction of symptoms in short-term trials. Long-term efficacy remains poorly characterized. Bupropion is not recommended for the treatment of eating disorders due to an increased risk of seizure.
Similar recommendations apply to binge eating disorder. SSRIs provide short-term reductions in binge eating behavior, but have not been associated with significant weight loss.
Clinical trials have generated mostly negative results for the use of SSRIs in the treatment of anorexia nervosa. Treatment guidelines from the National Institute of Health and Care Excellence recommend against the use of SSRIs in this disorder. Those from the American Psychiatric Association note that SSRIs confer no advantage regarding weight gain, but that they may be used for the treatment of co-existing depressive, anxiety, or obsessive–compulsive disorders.
A 2012 meta-analysis concluded that antidepressants treatment favorably affects pain, health-related quality of life, depression, and sleep in fibromyalgia syndrome. Tricyclics appear to be the most effective class, with moderate effects on pain and sleep and small effects on fatigue and health-related quality of life. The fraction of people experiencing a 30% pain reduction on tricyclics was 48% versus 28% for placebo. For SSRIs and SNRIs the fraction of people experiencing a 30% pain reduction was 36% (20% in the placebo comparator arms) and 42% (32% in the corresponding placebo comparator arms). Discontinuation of treatment due to side effects was common. Antidepressants including amitriptyline, fluoxetine, duloxetine, milnacipran, moclobemide, and pirlindole are recommended by the European League Against Rheumatism (EULAR) for the treatment of fibromyalgia based on "limited evidence".
A 2014 meta-analysis from the Cochrane Collaboration found the antidepressant duloxetine to be effective for the treatment of pain resulting from diabetic neuropathy. The same group reviewed data for amitriptyline in the treatment of neuropathic pain and found limited useful randomized clinical trial data. They concluded that the long history of successful use in the community for the treatment of fibromyalgia and neuropathic pain justified its continued use. The group was concerned about the potential for overestimating the amount of pain relief provided by amitriptyline, and highlighted that only a small number of people will experience significant pain relief by taking this medication.
Antidepressants may be modestly helpful for treating people who both have depression and alcohol dependence, however the evidence supporting this association of low quality. Buproprion is used to help people stop smoking.
Almost any medication involved with serotonin regulation has the potential to cause serotonin toxicity (also known as serotonin syndrome) – an excess of serotonin that can induce mania, restlessness, agitation, emotional lability, insomnia and confusion as its primary symptoms. Although the condition is serious, it is not particularly common, generally only appearing at high doses or while on other medications. Assuming proper medical intervention has been taken (within about 24 hours) it is rarely fatal.
MAOIs tend to have pronounced (sometimes fatal) interactions with a wide variety of medications and over-the-counter drugs. If taken with foods that contain very high levels of tyramine (e.g., mature cheese, cured meats, or yeast extracts), they may cause a potentially lethal hypertensive crisis. At lower doses the person may be bothered by only a headache due to an increase in blood pressure.
In response to these adverse effects, a different type of MAOI has been developed: the reversible inhibitor of monoamine oxidase A (RIMA) class of drugs. Their primary advantage is that they do not require the person to follow a special diet, while being purportedly effective as SSRIs and tricyclics in treating depressive disorders.
SSRI use in pregnancy has been associated with a variety of risks with varying degrees of proof of causation. As depression is independently associated with negative pregnancy outcomes, determining the extent to which observed associations between antidepressant use and specific adverse outcomes reflects a causative relationship has been difficult in some cases. In other cases, the attribution of adverse outcomes to antidepressant exposure seems fairly clear.
SSRI use in pregnancy is associated with an increased risk of spontaneous abortion of about 1.7-fold, and is associated with preterm birth and low birth weight.
A systematic review of the risk of major birth defects in antidepressant-exposed pregnancies found a small increase (3% to 24%) in the risk of major malformations and a risk of cardiovascular birth defects that did not differ from non-exposed pregnancies. A study of fluoxetine-exposed pregnancies found a 12% increase in the risk of major malformations that just missed statistical significance. Other studies have found an increased risk of cardiovascular birth defects among depressed mothers not undergoing SSRI treatment, suggesting the possibility of ascertainment bias, e.g. that worried mothers may pursue more aggressive testing of their infants. Another study found no increase in cardiovascular birth defects and a 27% increased risk of major malformations in SSRI exposed pregnancies. The FDA advises for the risk of birth defects with the use of paroxetine and the MAOI should be avoided.
A 2013 systematic review and meta-analysis found that antidepressant use during pregnancy was statistically significantly associated with some pregnancy outcomes, such as gestational age and preterm birth, but not with other outcomes. The same review cautioned that because differences between the exposed and unexposed groups were small, it was doubtful whether they were clinically significant.
A neonate (infant less than 28 days old) may experience a withdrawal syndrome from abrupt discontinuation of the antidepressant at birth. Antidepressants have been shown to be present in varying amounts in breast milk, but their effects on infants are currently unknown.
Moreover, SSRIs inhibit nitric oxide synthesis, which plays an important role in setting vascular tone. Several studies have pointed to an increased risk of prematurity associated with SSRI use, and this association may be due to an increase risk of pre-eclampsia of pregnancy.
Another possible problem with antidepressants is the chance of antidepressant-induced mania or hypomania in patients with or without a diagnosis of bipolar disorder. Many cases of bipolar depression are very similar to those of unipolar depression. Therefore, the patient can be misdiagnosed with unipolar depression and be given antidepressants. Studies have shown that antidepressant-induced mania can occur in 20–40% of bipolar patients. For bipolar depression, antidepressants (most frequently SSRIs) can exacerbate or trigger symptoms of hypomania and mania.
Studies have shown that the use of antidepressants is correlated with an increased risk of suicidal behaviour and thinking (suicidality) in those aged under 25. This problem has been serious enough to warrant government intervention by the US Food and Drug Administration (FDA) to warn of the increased risk of suicidality during antidepressant treatment. According to the FDA, the heightened risk of suicidality is within the first one to two months of treatment. The National Institute for Health and Care Excellence (NICE) places the excess risk in the "early stages of treatment". A meta-analysis suggests that the relationship between antidepressant use and suicidal behavior or thoughts is age-dependent. Compared to placebo the use of antidepressants is associated with an increase in suicidal behavior or thoughts among those aged under 25 (OR=1.62). This increase in suicidality approaches that observed in children and adolescents. There is no effect or possibly a mild protective effect among those aged 25 to 64 (OR=0.79). Antidepressant treatment has a protective effect against suicidality among those aged 65 and over (OR=0.37).
In a study of 1022 outpatients, overall sexual dysfunction with all antidepressants averaged 59.1% with SSRIs values between 57 and 73%, mirtazapine 24%, nefazodone 8%, amineptine 7% and moclobemide 4%. Moclobemide, a selective reversible MAO-A inhibitor, does not cause sexual dysfunction, and can actually lead to an improvement in all aspects of sexual function.
Bupropion, a weak NDRI and nicotinic antagonist, may be useful in treating reduced libido as a result of SSRI treatment.
Changes in weight
Changes in appetite or weight are common among antidepressants, but largely drug-dependent and are related to which neurotransmitters they affect. Mirtazapine and paroxetine, for example, have the effect of weight gain and/or increased appetite, while others (such as bupropion and venlafaxine) achieve the opposite effect.
The antihistaminic properties of certain TCA- and TeCA-class antidepressants have been shown to contribute to the common side-effects of increased appetite and weight gain associated with these classes of medication.
Antidepressant discontinuation syndrome, also called antidepressant withdrawal syndrome, is a condition that can occur following the interruption, reduction, or discontinuation of antidepressant medication. The symptoms may include flu-like symptoms, trouble sleeping, nausea, poor balance, sensory changes, and anxiety. The problem usually begins within three days and may last for several months. Rarely psychosis may occur.
Methods of prevention include gradually decreasing the dose among those who wish to stop, though it is possible for symptoms to occur with tapering. Treatment may include restarting the medication and slowly decreasing the dose. People may also be switched to the long acting antidepressant fluoxetine which can then be gradually decreased.
Approximately 20–50% of people who suddenly stop an antidepressant develop an antidepressant discontinuation syndrome. The condition is generally not serious. Though about half of people with symptoms describe them as severe. Some restart antidepressants due to the severity of the symptoms.
SSRIs appear to cause emotional blunting, or numbness in some people who take them. This is a reduction in extremes of emotion, both positive and negative. While the person may feel less depressed, they may also feel less happiness or empathy in some situations. This may be cause for a dose reduction or medication change. The exact mechanism is unknown.
The earliest and probably most widely accepted scientific theory of antidepressant action is the monoamine hypothesis (which can be traced back to the 1950s), which states that depression is due to an imbalance (most often a deficiency) of the monoamine neurotransmitters (namely serotonin, norepinephrine and dopamine). It was originally proposed based on the observation that certain hydrazine anti-tuberculosis agents produce antidepressant effects, which was later linked to their inhibitory effects on monoamine oxidase, the enzyme that catalyses the breakdown of the monoamine neurotransmitters. All currently marketed antidepressants have the monoamine hypothesis as their theoretical basis, with the possible exception of agomelatine which acts on a dual melatonergic-serotonergic pathway. Despite the success of the monoamine hypothesis it has a number of limitations: for one, all monoaminergic antidepressants have a delayed onset of action of at least a week; and secondly, there are a sizeable portion (>40%) of depressed patients that do not adequately respond to monoaminergic antidepressants. A number of alternative hypotheses have been proposed, including the glutamate, neurogenic, epigenetic, cortisol hypersecretion and inflammatory hypotheses.
Adjunct medications are an umbrella term used to describe substances that increase the potency or "enhance" antidepressants. They work by affecting variables very close to the antidepressant, sometimes affecting a completely different mechanism of action. This may be attempted when depression treatments have not been successful in the past.
Common types of adjunct medication techniques generally fall into the following categories:
Two or more antidepressants taken together
From the same class (affecting the same area of the brain, often at a much higher level)
From different classes (affecting multiple parts of the brain not covered simultaneously by either drug alone)
It is unknown if undergoing psychological therapy at the same time as taking anti-depressants enhances the anti-depressive effect of the medication.
Less common adjunct medication
Lithium has been used to augment antidepressant therapy in those who have failed to respond to antidepressants alone. Furthermore, lithium dramatically decreases the suicide risk in recurrent depression. There is some evidence for the addition of a thyroid hormone, triiodothyronine, in patients with normal thyroid function.
Psychopharmacologists have also tried adding a stimulant, in particular, d-amphetamine. However, the use of stimulants in cases of treatment-resistant depression is relatively controversial. A review article published in 2007 found psychostimulants may be effective in treatment-resistant depression with concomitant antidepressant therapy, but a more certain conclusion could not be drawn due to substantial deficiencies in the studies available for consideration, and the somewhat contradictory nature of their results.
Before the 1950s, opioids and amphetamines were commonly used as antidepressants. Their use was later restricted due to their addictive nature and side effects. Extracts from the herb St John's wort have been used as a "nerve tonic" to alleviate depression.
Isoniazid, iproniazid, and imipramine
In 1951, Irving Selikoff and Edward H. Robitzek [de], working out of Sea View Hospital on Staten Island, began clinical trials on two new anti-tuberculosis agents developed by Hoffman-LaRoche, isoniazid and iproniazid. Only patients with a poor prognosis were initially treated; nevertheless, their condition improved dramatically. Selikoff and Robitzek noted "a subtle general stimulation ... the patients exhibited renewed vigor and indeed this occasionally served to introduce disciplinary problems." The promise of a cure for tuberculosis in the Sea View Hospital trials was excitedly discussed in the mainstream press.
In 1952, learning of the stimulating side effects of isoniazid, the Cincinnati psychiatrist Max Lurie tried it on his patients. In the following year, he and Harry Salzer reported that isoniazid improved depression in two thirds of their patients and coined the term antidepressant to describe its action. A similar incident took place in Paris, where Jean Delay, head of psychiatry at Sainte-Anne Hospital, heard of this effect from his pulmonology colleagues at Cochin Hospital. In 1952 (before Lurie and Salzer), Delay, with the resident Jean-Francois Buisson [fr], reported the positive effect of isoniazid on depressed patients. The mode of antidepressant action of isoniazid is still unclear. It is speculated that its effect is due to the inhibition of diamine oxidase, coupled with a weak inhibition of monoamine oxidase A.
Selikoff and Robitzek also experimented with another anti-tuberculosis drug, iproniazid; it showed a greater psychostimulant effect, but more pronounced toxicity. Later, Jackson Smith, Gordon Kamman, George E. Crane, and Frank Ayd, described the psychiatric applications of iproniazid. Ernst Zeller found iproniazid to be a potent monoamine oxidase inhibitor. Nevertheless, iproniazid remained relatively obscure until Nathan S. Kline, the influential head of research at Rockland State Hospital, began to popularize it in the medical and popular press as a "psychic energizer". Roche put a significant marketing effort behind iproniazid. Its sales grew until it was recalled in 1961, due to reports of lethal hepatotoxicity.
Attempting to improve the effectiveness of chlorpromazine, Kuhn – in conjunction with the GeigyPharmaceutical Company – discovered the compound "G 22355", later renamed imipramine. Imipramine had a beneficial effect in patients with depression who showed mental and motor retardation. Kuhn described his new compound as a "thymoleptic" "taking hold of the emotions," in contrast with neuroleptics, "taking hold of the nerves" in 1955–56. These gradually became established, resulting in the patent and manufacture in the US in 1951 by Häfliger and SchinderA.
Antidepressants became prescription drugs in the 1950s. It was estimated that no more than 50 to 100 individuals per million suffered from the kind of depression that these new drugs would treat, and pharmaceutical companies were not enthusiastic in marketing for this small market. Sales through the 1960s remained poor compared to the sales of tranquilizers, which were being marketed for different uses. Imipramine remained in common use and numerous successors were introduced. The use of monoamine oxidase inhibitors (MAOI) increased after the development and introduction of "reversible" forms affecting only the MAO-A subtype of inhibitors, making this drug safer to use.
By the 1960s, it was thought that the mode of action of tricyclics was to inhibit norepinephrine reuptake. However, norepinephrine reuptake became associated with stimulating effects. Later tricyclics were thought to affect serotonin as proposed in 1969 by Carlsson and Lindqvist as well as Lapin and Oxenkrug.[medical citation needed]
St John's wort fell out of favor in most countries through the 19th and 20th centuries, except in Germany, where Hypericum extracts were eventually licensed, packaged and prescribed. Small-scale efficacy trials were carried out in the 1970s and 1980s, and attention grew in the 1990s following a meta-analysis. It remains an over-the-counter drug (OTC) supplement in most countries. Research continues to investigate its active component hyperforin, and to further understand its mode of action.
Society and culture
In the United States, antidepressants were the most commonly prescribed medication in 2013. Of the estimated 16 million "long term" (over 24 months) users, roughly 70 percent are female.
In the UK, figures reported in 2010 indicated that the number of antidepressant prescribed by the National Health Service (NHS) almost doubled over a decade. Further analysis published in 2014 showed that number of antidepressants dispensed annually in the community went up by 25 million in the 14 years between 1998 and 2012, rising from 15 million to 40 million. Nearly 50% of this rise occurred in the four years after the 2008 banking crash, during which time the annual increase in prescriptions rose from 6.7% to 8.5%. These sources also suggest that aside from the recession, other factors that may influence changes in prescribing rates may include: improvements in diagnosis, a reduction of the stigma surrounding mental health, broader prescribing trends, GP characteristics, geographical location and housing status. Another factor that may contribute to increasing consumption of antidepressants is the fact that these medications now are used for other conditions including social anxiety and post traumatic stress.
As of 2003, worldwide, 30 to 60% of people didn't follow their practitioner's instructions about taking their antidepressants, and as of 2013 in the US, it appeared that around 50% of people did not take their antidepressants as directed by their practitioner.
When people fail to take their antidepressants, there is a greater risk that the drug won't help, that symptoms get worse, that they miss work or are less productive at work, and that the person may be hospitalized. This also increases costs for caring for them.
Social science perspective
In looking at the issue of antidepressant use, some academics have highlighted the need to examine the use of antidepressants and other medical treatments in cross-cultural terms, due to the fact that various cultures prescribe and observe different manifestations, symptoms, meanings and associations of depression and other medical conditions within their populations. These cross-cultural discrepancies, it has been argued, then have implications on the perceived efficacy and use of antidepressants and other strategies in the treatment of depression in these different cultures. In India antidepressants are largely seen as tools to combat marginality, promising the individual the ability to re-integrate into society through their use—a view and association not observed in the West.
Because most antidepressants function by inhibiting the reuptake of neurotransmitters serotonin, dopamine, and norepinepherine these drugs can interfere with natural neurotransmitter levels in other organisms impacted by indirect exposure. Antidepressants fluoxetine and sertraline have been detected in aquatic organisms residing in effluent dominated streams. The presence of antidepressants in surface waters and aquatic organisms has caused concern because ecotoxicological effects to aquatic organisms due to fluoxetine exposure have been demonstrated.
Coral reef fish have been demonstrated to modulate aggressive behavior through serotonin. Artificially increasing serotonin levels in crustaceans can temporarily reverse social status and turn subordinates into aggressive and territorial dominant males.
Exposure to fluoxetine has been demonstrated to increase serotonergic activity in fish, subsequently reducing aggressive behavior. Perinatal exposure to fluoxetine at relevant environmental concentrations has been shown to lead to significant modifications of memory processing in 1-month-old cuttlefish. This impairment may disadvantage cuttlefish and decrease their survival. Somewhat less than 10% of orally administered fluoxetine is excreted from humans unchanged or as glucuronide.
^Zhou X, Ravindran AV, Qin B, Del Giovane C, Li Q, Bauer M, Liu Y, Fang Y, da Silva T, Zhang Y, Fang L, Wang X, Xie P (April 2015). "Comparative efficacy, acceptability, and tolerability of augmentation agents in treatment-resistant depression: systematic review and network meta-analysis". J Clin Psychiatry. 76 (4): e487–98. doi:10.4088/JCP.14r09204. PMID25919841. Quetiapine and aripiprazole appear to be the most robust evidence-based options for augmentation therapy in patients with treatment-resistant depression
^Borges S, Chen YF, Laughren TP, Temple R, Patel HD, David PA, Mathis M, Unger E, Yang P, Khin NA (2014). "Review of maintenance trials for major depressive disorder: a 25-year perspective from the US Food and Drug Administration". J Clin Psychiatry. 75 (3): 205–14. doi:10.4088/JCP.13r08722. PMID24717376.
^"Depression in Adults (update)"(PDF). National Collaborating Centre for Mental Health Commissioned by the National Institute for Health and Care Excellence. www.nice.org.uk. 2009. pp. 282–292. Archived from the original(PDF) on 12 June 2013. Retrieved 20 November 2013.
^Kirsch I, Moore TJ, Scoboria A, Nicholls SS (2002). "The emperor's new drugs: An analysis of antidepressant medication data submitted to the U.S. Food and Drug Administration". Prevention & Treatment. 5. doi:10.1037/1522-37220.127.116.113a.
^Whittington CJ, Kendall T, Fonagy P, Cottrell D, Cotgrove A, Boddington E (2004). "Selective serotonin reuptake inhibitors in childhood depression: Systematic review of published versus unpublished data". The Lancet. 363 (9418): 1341–5. doi:10.1016/S0140-6736(04)16043-1. PMID15110490.
^Walsh BT, Seidman SN, Sysko R, Gould M (2002). "Placebo Response in Studies of Major Depression: Variable, Substantial, and Growing". JAMA. 287 (14): 1840–7. doi:10.1001/jama.287.14.1840. PMID11939870.
^Freeman MP, Mischoulon D, Tedeschini E, Goodness T, Cohen LS, Fava M, Papakostas GI (2010). "Complementary and alternative medicine for major depressive disorder: a meta-analysis of patient characteristics, placebo-response rates, and treatment outcomes relative to standard antidepressants". J Clin Psychiatry. 71 (6): 682–8. doi:10.4088/JCP.10r05976blu. PMID20573327.
^Fava M, Rush AJ, Wisniewski SR, Nierenberg AA, Alpert JE, McGrath PJ, Thase ME, Warden D, Biggs M, Luther JF, Niederehe G, Ritz L, Trivedi MH (2006). "A Comparison of Mirtazapine and Nortriptyline Following Two Consecutive Failed Medication Treatments for Depressed Outpatients: A STAR*D Report". The American Journal of Psychiatry. 163 (7): 1161–72. doi:10.1176/appi.ajp.163.7.1161. PMID16816220.
^ abTrivedi MH, Fava M, Wisniewski SR, Thase ME, Quitkin F, Warden D, Ritz L, Nierenberg AA, Lebowitz BD, Biggs MM, Luther JF, Shores-Wilson K, Rush AJ (2006). "Medication Augmentation after the Failure of SSRIs for Depression". New England Journal of Medicine. 354 (12): 1243–52. doi:10.1056/NEJMoa052964. PMID16554526.
^Trivedi MH, Rush AJ, Wisniewski SR, Nierenberg AA, Warden D, Ritz L, Norquist G, Howland RH, Lebowitz B, McGrath PJ, Shores-Wilson K, Biggs MM, Balasubramani GK, Fava M (2006). "Evaluation of Outcomes with Citalopram for Depression Using Measurement-Based Care in STAR*D: Implications for Clinical Practice". American Journal of Psychiatry. 163 (1): 28–40. doi:10.1176/appi.ajp.163.1.28. PMID16390886.
^Warden D, Trivedi MH, Wisniewski SR, Davis L, Nierenberg AA, Gaynes BN, Zisook S, Hollon SD, Balasubramani GK, Howland R, Fava M, Stewart JW, Rush AJ (2007). "Predictors of attrition during initial (citalopram) treatment for depression: a STAR*D report". Am J Psychiatry. 164 (8): 1189–97. doi:10.1176/appi.ajp.2007.06071225. PMID17671281.
^Rush AJ, Trivedi MH, Wisniewski SR, Stewart JW, Nierenberg AA, Thase ME, Ritz L, Biggs MM, Warden D, Luther JF, Shores-Wilson K, Niederehe G, Fava M (2006). "Bupropion-SR, Sertraline, or Venlafaxine-XR after Failure of SSRIs for Depression". New England Journal of Medicine. 354 (12): 1231–42. doi:10.1056/NEJMoa052963. PMID16554525.
^Rush AJ, Trivedi MH, Wisniewski SR, et al. (November 2006). "Acute and longer-term outcomes in depressed outpatients requiring one or several treatment steps: a STAR*D report". Am J Psychiatry. 163 (11): 1905–17. doi:10.1176/appi.ajp.163.11.1905. PMID17074942.
^Warden D, Rush AJ, Trivedi MH, Fava M, Wisniewski SR (2007). "The STAR*D Project results: A comprehensive review of findings". Current Psychiatry Reports. 9 (6): 449–59. doi:10.1007/s11920-007-0061-3. PMID18221624.
^Baghai TC, Möller HJ, Rupprecht R (2006). "Recent Progress in Pharmacological and Non-Pharmacological Treatment Options of Major Depression". Current Pharmaceutical Design. 12 (4): 503–15. doi:10.2174/138161206775474422. PMID16472142.
^ abRuhé HG, Huyser J, Swinkels JA, Schene AH (2006). "Switching Antidepressants After a First Selective Serotonin Reuptake Inhibitor in Major Depressive Disorder". The Journal of Clinical Psychiatry. 67 (12): 1836–55. doi:10.4088/JCP.v67n1203. PMID17194261.
^Mischoulon D, Nierenberg AA, Kizilbash L, Rosenbaum JF, Fava M (2000). "Strategies for managing depression refractory to selective serotonin reuptake inhibitor treatment: A survey of clinicians". Canadian Journal of Psychiatry. 45 (5): 476–81. doi:10.1177/070674370004500509. PMID10900529.
^Lam RW, Wan DD, Cohen NL, Kennedy SH (2002). "Combining Antidepressants for Treatment-Resistant Depression". The Journal of Clinical Psychiatry. 63 (8): 685–93. doi:10.4088/JCP.v63n0805. PMID12197448.
^Goss AJ, Kaser M, Costafreda SG, Sahakian BJ, Fu CH (2013). "Modafinil augmentation therapy in unipolar and bipolar depression: a systematic review and meta-analysis of randomized controlled trials". The Journal of Clinical Psychiatry. 74 (11): 1101–7. doi:10.4088/JCP.13r08560. PMID24330897.
^Geddes JR, Carney SM, Davies C, Furukawa TA, Kupfer DJ, Frank E, Goodwin GM (2003). "Relapse prevention with antidepressant drug treatment in depressive disorders: A systematic review". The Lancet. 361 (9358): 653–61. doi:10.1016/S0140-6736(03)12599-8. PMID12606176.
^Fineberg, N. A.; Brown, A; Reghunandanan, S; Pampaloni, I (2012). "Evidence-based pharmacotherapy of obsessive-compulsive disorder". The International Journal of Neuropsychopharmacology. 15 (8): 1173–91. doi:10.1017/S1461145711001829. hdl:2299/216. PMID22226028.
^Häuser W, Wolfe F, Tölle T, Uçeyler N, Sommer C (April 2012). "The role of antidepressants in the management of fibromyalgia syndrome: a systematic review and meta-analysis". CNS Drugs. 26 (4): 297–307. doi:10.2165/11598970-000000000-00000. PMID22452526.
^Einarson TR, Kennedy D, Einarson A (2012). "Do findings differ across research design? The case of antidepressant use in pregnancy and malformations". J Popul Ther Clin Pharmacol. 19 (2): e334–48. PMID22946124.
^Montejo AL, Llorca G, Izquierdo JA, Rico-Villademoros F (2001). "Incidence of sexual dysfunction associated with antidepressant agents: a prospective multicenter study of 1022 outpatients. Spanish Working Group for the Study of Psychotropic-Related Sexual Dysfunction". J Clin Psychiatry. 62 Suppl 3: 10–21. PMID11229449.
^Ozmenler NK, Karlidere T, Bozkurt A, Yetkin S, Doruk A, Sutcigil L, Cansever A, Uzun O, Ozgen F, Ozsahin A (2008). "Mirtazapine augmentation in depressed patients with sexual dysfunction due to selective serotonin reuptake inhibitors". Hum Psychopharmacol. 23 (4): 321–6. doi:10.1002/hup.929. PMID18278806.
^Fornaro, M; Anastasia, A; Novello, S; Fusco, A; Pariano, R; De Berardis, D; Solmi, M; Veronese, N; Stubbs, B; Vieta, E; Berk, M; de Bartolomeis, A; Carvalho, AF (29 October 2018). "The emergence of loss of efficacy during antidepressant drug treatment for major depressive disorder: An integrative review of evidence, mechanisms, and clinical implications". Pharmacological Research. doi:10.1016/j.phrs.2018.10.025. PMID30385364.
^Pringle, A; McCabe, C; Cowen, PJ; Harmer, CJ (August 2013). "Antidepressant treatment and emotional processing: can we dissociate the roles of serotonin and noradrenaline?". Journal of Psychopharmacology (Oxford, England). 27 (8): 719–31. doi:10.1177/0269881112474523. PMID23392757.
^ abMaes M, Yirmyia R, Noraberg J, Brene S, Hibbeln J, Perini G, Kubera M, Bob P, Lerer B, Maj M (March 2009). "The inflammatory & neurodegenerative (I&ND) hypothesis of depression: leads for future research and new drug developments in depression". Metabolic Brain Disease. 24 (1): 27–53. doi:10.1007/s11011-008-9118-1. PMID19085093.
^Cashman, JR; Ghirmai, S (2009). "Inhibition of serotonin and norepinephrine reuptake and inhibition of phosphodiesterase by multi-target inhibitors as potential agents for depression". Bioorganic & Medicinal Chemistry. 17 (19): 6890–7. doi:10.1016/j.bmc.2009.08.025. PMID19740668.
^Muntner, Stephen M. Stahl ; with illustrations by Nancy (2013). Stahl's essential psychopharmacology : neuroscientific basis and practical application (4th ed.). Cambridge: Cambridge University Press. ISBN978-1107686465.
^Gasior M, Bergman J, Kallman MJ, Paronis CA (April 2005). "Evaluation of the reinforcing effects of monoamine reuptake inhibitors under a concurrent schedule of food and i.v. drug delivery in rhesus monkeys". Neuropsychopharmacology. 30 (4): 758–64. doi:10.1038/sj.npp.1300593. PMID15526000.
^ abTatsumi M, Groshan K, Blakely RD, Richelson E (1997). "Pharmacological profile of antidepressants and related compounds at human monoamine transporters". Eur J Pharmacol. 340 (2–3): 249–258. doi:10.1016/S0014-2999(97)01393-9. PMID9537821.
^Buigues, J; Vallejo, J (1987). "Therapeutic response to phenelzine in patients with panic disorder and agoraphobia with panic attacks". Journal of Clinical Psychiatry. 48 (2): 55–9. PMID3542985.
^Liebowitz, MR; Schneier, FR; Campeas, R; Hollander, E; Hatterer, J; Fyer, A; et al. (1992). "Phenelzine vs atenolol in social phobia: A placebo-controlled comparison". Archives of General Psychiatry. 49 (4): 290–300. doi:10.1001/archpsyc.49.4.290. PMID1558463.
^Versiani M, Nardi AE, Mundim FD, Alves AB, Liebowitz MR, Amrein R. Pharmacotherapy of social phobia. A controlled study with moclobemide and phenelzine. BJP [Internet]. 1992 Sep 1 [cited 2013 Oct 4];161(3):353–60. Available from: Versiani, M.; Nardi, A. E.; Mundim, F. D.; Alves, A. B.; Liebowitz, M. R.; Amrein, R. (1992). "Pharmacotherapy of Social Phobia". British Journal of Psychiatry. 161 (3): 353–360. doi:10.1192/bjp.161.3.353. Archived from the original on 20 November 2015. Retrieved 20 November 2015.
^Heimberg, RG; Liebowitz, MR; Hope, DA; et al. (1998). "Cognitive behavioral group therapy vs phenelzine therapy for social phobia: 12-week outcome". Arch Gen Psychiatry. 55 (12): 1133–41. doi:10.1001/archpsyc.55.12.1133. PMID9862558.
^Davidson, J; Ingram, J; Kilts, C (1987). "A pilot study of phenelzine in the treatment of post-traumatic stress disorder". The British Journal of Psychiatry. 150 (2): 252–5. doi:10.1192/bjp.150.2.252.
^Nierenberg AA, Fava M, Trivedi MH, Wisniewski SR, Thase ME, McGrath PJ, Alpert JE, Warden D, Luther JF, Niederehe G, Lebowitz B, Shores-Wilson K, Rush AJ (2006). "A comparison of lithium and T(3) augmentation following two failed medication treatments for depression: A STAR*D report". American Journal of Psychiatry. 163 (9): 1519–30. doi:10.1176/appi.ajp.163.9.1519. PMID16946176.
^Stahl, Stephen M. (2011). The Prescriber's Guide (Stahl's Essential Psychopharmacology). Cambridge University Press. p. 39.
^Czygan FC (2003). "Kulturgeschichte und Mystik des Johanniskrauts: Vom 2500 Jahre alten Apotropaikum zum aktuellen Antidepressivum" [From a 2500-year-old apotropic comes a current antidepressive. The cultural history and mistique of St. John's wort]. Pharmazie in Unserer Zeit (in German). 32 (3): 184–90. doi:10.1002/pauz.200390062. PMID12784538.
^Healy D (1996). The psychopharmacologists: interviews. London: Chapman and Hall. p. 8. ISBN978-1-86036-008-4.
^Healy D (1998). The Psychopharmacologists: Volume 2. A Hodder Arnold Publication. pp. 132–4. ISBN978-1-86036-010-7.
^Robitzek EH, Selikoff IJ, Mamlok E, Tendlau A (1953). "Isoniazid and Its Isopropyl Derivative in the Therapy of Tuberculosis in Humans: Comparative Therapeutic and Toxicologic Properties". Chest. 23 (1): 1–15. doi:10.1378/chest.23.1.1. PMID12998444.
^Nathan PJ (2001). "Hypericum perforatum (St John's Wort): A non-selective reuptake inhibitor? A review of the recent advances in its pharmacology". Journal of Psychopharmacology. 15 (1): 47–54. doi:10.1177/026988110101500109. PMID11277608.
^Kaplan, Jessica E.; Keeley, Robert D.; Engel, Matthew; Emsermann, Caroline; Brody, David (July 2013). "Aspects of patient and clinician language predict adherence to antidepressant medication". Journal of the American Board of Family Medicine: JABFM. 26 (4): 409–420. doi:10.3122/jabfm.2013.04.120201. PMID23833156.
^ abHo, SC; Chong, HY; Chaiyakunapruk, N; Tangiisuran, B; Jacob, SA (15 March 2016). "Clinical and economic impact of non-adherence to antidepressants in major depressive disorder: A systematic review". Journal of Affective Disorders. 193: 1–10. doi:10.1016/j.jad.2015.12.029. PMID26748881.
^Fong PP (2001). "Antidepressants in Aquatic Organisms: A Wide Range of Effects". In Daughton CG, Jones-Lepp TJ. Pharmaceuticals and personal care products in the environment: scientific and regulatory issues. Washington, DC: American Chemical Society. pp. 264–281. ISBN978-0-8412-3739-1.
^Brooks BW, Chambliss CK, Stanley JK, Ramirez A, Banks KE, Johnson RD, Lewis RJ (2005). "Determination of select antidepressants in fish from an effluent-dominated stream". Environ. Toxicol. Chem. 24 (2): 464–9. doi:10.1897/04-081r.1. PMID15720009.
^Di Poi C, Darmaillacq AS, Dickel L, Boulouard M, Bellanger C (2013). "Effects of perinatal exposure to waterborne fluoxetine on memory processing in the cuttlefish Sepia officinalis". Aquat. Toxicol. 132–133: 84–91. doi:10.1016/j.aquatox.2013.02.004. PMID23474317.
^Nentwig G (2007). "Effects of pharmaceuticals on aquatic invertebrates. Part II: the antidepressant drug fluoxetine". Arch. Environ. Contam. Toxicol. 52 (2): 163–70. doi:10.1007/s00244-005-7190-7. PMID17160491.