Flavoxate-d5 is intended for use as an internal standard for the quantification of flavoxate by GC- or LC-MS. Flavoxate is an inhibitor of L-type calcium channels and an antimuscarinic agent.1 It induces relaxation of potassium-precontracted isolated human urinary bladder detrusor muscle (IC50 = 2 µM) and reduces contractions induced by the acetylcholine receptor agonist carbachol or calcium in isolated rat detrusor strips.1,2 Microinjection of flavoxate (0.68 µg/animal) into the oral pontine reticular nucleus inhibits reflex micturition in decerebrated cats, and intravenous or intracerebroventricular administration reduces isovolumetric rhythmic bladder contractions in rats.2 Formulations containing flavoxate have previously been used in the treatment of frequent or urgent urination, increased nocturnal urination, bladder pain, and urinary incontinence.
1.Tomoda, T., Aishima, M., Takano, N., et al.The effects of flavoxate hydrochloride on voltage-dependent L-type Ca2+ currents in human urinary bladderBrit. J. Pharmacol.146(1)25-32(2005) 2.Kimura, Y., Sasaki, Y., Hamada, K., et al.Mechanisms of the suppression of the bladder activity by flavoxateInt. J. Urol.3(3)218-227(1996)