A case report on antimuscarinic drug-induced confusion: A cognitive side effect

Oxybutynin and tolterodine are antimuscarinic agents indicated for the treatment of overactive bladder, which is manifested as urinary incontinence, urgency, or frequency. Oxybutynin works by competitively inhibiting acetylcholine at postganglionic muscarinic receptors M 1 , M 2 , and M 3 , causing smooth muscles in the bladder to relax, and tolterodine works by competitively binding to the bladder’s muscarinic M 3 receptors, reducing bladder contraction by raising the tone of the internal urethral sphincter and decreasing the tone of the detrusor muscle. Central nervous system’s (CNS) side effects are attributed by the oxybutynin’s anticholinergic actions. There is evidence of several CNS effects associated with anticholinergic medications, including agitation, confusion, disorientation, somnolence, memory loss, and hallucinations. These adverse effects occur in patients during the first few months of treatment or when the dose of oxybutynin is increased. This case report emphasizes the confused behavior of the patient on taking oxybutynin and tolterodine and also the cognitive side effects experienced by the patient.