Pilostat and Systemic vagotonic effects

Topically applied cholinergic agents are systemically absorbed, with the potential for producing rare but clinically significant systemic effects, including urinary incontinence, tightness of the bladder, increased gastric contractility and acid secretion, bradycardia, severe hypotension, bronchospasm, seizures, and coma. Increases in blood pressure may occur rarely due to a nicotinic effect on sympathetic ganglia. Therapy with ophthalmic cholinergic agents, particularly the long-acting cholinesterase inhibitors (e.g., demecarium and echothiophate), should be administered cautiously in patients with corneal abrasion (which may increase drug penetration), bronchospastic diseases, spastic gastrointestinal disturbances, urinary tract obstruction, peptic ulcer, pronounced bradycardia and hypotension, vascular hypertension, acute cardiac failure, recent myocardial infarction, epilepsy, parkinsonism, and other conditions that may respond adversely to vagotonic effects. The usual precautions should be followed to minimize the risk of systemic toxicity, including digital compression of the nasolacrimal ducts (1 to 2 minutes) following instillation to limit drainage into the nasal chamber, where extensive absorption may occur, and washing hands after use to prevent skin absorption. Excessive cholinergic effects may be reversed with parenterally administered atropine.