Antikolinergit

Antikolinergit, or anticholinergics, are a class of drugs that block the action of the neurotransmitter acetylcholine at muscarinic receptors (M1–M5). They can be natural alkaloids such as atropine and scopolamine or synthetic compounds such as benztropine, trihexyphenidyl, glycopyrrolate, oxybutynin, and tolterodine. The drugs act as competitive antagonists at muscarinic receptors, reducing parasympathetic activity. Resulting effects include decreased secretions, relaxation of smooth muscle, and a faster heart rate; if the drug crosses the blood–brain barrier, it can produce cognitive and mood changes.

Antikolinergit have a range of clinical uses. In neurology and psychiatry, they help manage Parkinson’s disease symptoms such as tremor and rigidity and can counteract extrapyramidal side effects from antipsychotic medications. They are used as antispasmodics for gastrointestinal cramps and to reduce urgency in overactive bladder. Ophthalmic use includes pupil dilation and cycloplegia. Peripherally acting preparations are sometimes employed to reduce secretions before anesthesia or to treat excessive salivation.

Common adverse effects include dry mouth, blurred vision, constipation, urinary retention, and tachycardia. Central nervous system effects—such as confusion, delirium, dizziness, and memory impairment—are more likely with agents that cross the blood–brain barrier, and the risk is higher in older adults. Caution is advised in patients with glaucoma, urinary retention due to prostatic hypertrophy, or significant cognitive impairment. Drug interactions may occur with other anticholinergics, acetylcholinesterase inhibitors, and certain antidepressants.