In contrast to Bay K8644, which is not for clinical use, Ambroxol is a frequently used mucolytic drug that triggers lysosomal secretion by mobilizing calcium from acidic calcium stores. This effect does most likely not occur by a direct interaction between the drug and a lysosomal calcium channel, but indirectly by neutralizing the acidic pH within lysosomes. Calcium permeable ion channels in lysosomal membranes that may be activated by a luminal pH increase include two pore channels (TPCs), mucolipin TRP channels (TRPMLs) and purinergic receptors of the P2X channel type.
^Schramm M, Thomas G, Towart R, Franckowiak G (1983). "Activation of calcium channels by novel 1,4-dihydropyridines. A new mechanism for positive inotropics or smooth muscle stimulants". Arzneimittelforschung. 33 (9): 1268–72. PMID6196037.
^Fois, Giorgio; Hobi, Nina; Felder, Edward; Ziegler, Andreas; Miklavc, Pika; Walther, Paul; Radermacher, Peter; Haller, Thomas; Dietl, Paul (2015). "A new role for an old drug: Ambroxol triggers lysosomal exocytosis via pH-dependent Ca2+ release from acidic Ca2+ stores". Cell Calcium. 58 (6): 628–637. doi:10.1016/j.ceca.2015.10.002. PMID26560688.