Known brand names include Atropen and Isopto Atropine.
An injectable anticholinergic that blocks acetylcholine at muscarinic receptors. It speeds up a dangerously slow heart rate, dries secretions before and during surgery, and is the antidote for organophosphate insecticide, carbamate, and certain mushroom poisonings.
Atropine blocks acetylcholine, a nerve chemical that slows the heart and makes glands release saliva, sweat, and mucus. It does this at muscarinic receptors in the heart, glands, and smooth muscle. The block can be overcome if acetylcholine builds up to high levels, as happens when its normal breakdown is stopped. With acetylcholine blocked, the heart speeds up, secretions dry up, and the airways widen.
Given into a vein, its peak effects on heart rate and saliva come about 7 to 8 minutes later, and the body clears half of it from the blood in about 2 to 4 hours. A small dose can briefly slow the heart before the faster rate sets in. In poisoning, the aim is to ease airway tightening, dry the lungs, and improve oxygen levels. The faster heart rate raises the heart's oxygen needs and can worsen heart disease from narrowed arteries, and blocked sweating can cause fever in infants and small children.
Atropine is an injection used in emergencies to speed up a heart rate that is dangerously slow and causing symptoms. It is the antidote for poisoning by organophosphate or carbamate pesticides and by certain mushrooms. Before and during surgery, it dries up saliva and blocks nerve reflexes that can suddenly slow the heart. In all these uses, it temporarily blocks severe or life-threatening effects of acetylcholine, a nerve chemical.
It is given as a shot, usually into a vein, but it can also go into a muscle, under the skin, into the bone, or down a breathing tube. Both adults and children receive it, with children's amounts based on body weight. The label lists no situations in which it must never be used, but it warns that it can trigger acute glaucoma, block urine flow in people with an enlarged prostate, and thicken mucus in people with chronic lung disease.
Dry mouth, blurred vision, sensitivity to light, and a fast heart rate are common, and less sweating can make people overheat. Constipation and trouble urinating also happen. The label treats serious allergic reactions, worsening chest pain or heart damage in people with heart disease, a sudden type of glaucoma, blockage of the stomach outlet, and complete inability to urinate in men with an enlarged prostate as serious. Large doses can cause agitation, hallucinations, delirium, coma, and failure of breathing and circulation.