Common side effects are belching, bloating, stomach discomfort or upset, nausea, vomiting, indigestion, dizziness, and flushing. Uncommon and rare side effects include angina, palpitations, hypersensitivity, itchiness, rash, hives, bleeding, hallucinations, arrhythmias, and aseptic meningitis.
Contraindications include intolerance to pentoxifylline or other xanthine derivatives, recent retinal or cerebral haemorrhage, and risk factors for haemorrhage.
In a Cochrane systematic review on the use of Pentoxifylline for intermittent claudication in 2015, the following was concluded "The quality of included studies was generally low, and very large variability between studies was noted in reported findings including duration of trials, doses of pentoxifylline and distances participants could walk at the start of trials. Most included studies did not report on randomisation techniques or how treatment allocation was concealed, did not provide adequate information to permit judgement of selective reporting and did not report blinding of outcome assessors. Given all these factors, the role of pentoxifylline in intermittent claudication remains uncertain, although this medication was generally well tolerated by participants".
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