Atropine

Atropine is an alkaloid originally synthesized from Atropa belladonna. It is a racemic mixture of d-and l-hyoscyamine, of which only l-hyoscyamine is pharmacologically active.[A251670,L42835] Atropine is generally available as a sulfate salt and can be administered by intravenous, subcutaneous, intramuscular, intraosseous, endotracheal and ophthalmic methods. Oral atropine is only available in combination products.[A251660,L42840] Atropine is a competitive, reversible antagonist of muscarinic receptors that blocks the effects of acetylcholine and other choline esters.[A251660,L42815,L42825,L42835] It has a variety of therapeutic applications, including pupil dilation and the treatment of anticholinergic poisoning and symptomatic bradycardia in the absence of reversible causes.[A251660] Atropine is a relatively inexpensive drug and is included in the World Health Organization List of Essential Medicines.[A251675]