.png | width = 221 | CAS_number = 28797-61-7 | ATC_prefix = A02 | ATC_suffix = BX03 | ATC_supplemental = | PubChem = 4848 | DrugBank = APRD00515 | chemical_formula = C₁₉H₂₁N₅O₂ | molecular_weight = 351.403 g/mol | bioavailability = | protein_bound = | metabolism = | elimination_half-life = | pregnancy_category = | legal_status = | routes_of_administration = }}

Pirenzepine (markated by Merck Marker under the trade-name Gastrozepin) is used in the treatment of peptic ulcers, as it reduces gastric acid secretion and reduces muscle spasm. It is in a class of drugs known as Muscarinic (Acetylcholine) receptor antagonists - acetyl choline being the neurotransmitter of the parasympathetic nervous system which initiates the rest-and-digest state (as aposed to fight-or-flight), the result being an increase in gastric motility and digestion.

Pirenzepine has been investigated for use in myopia control^*.

Pharmacology