Anticholinergic toxicity occurs when there is an excess of anticholinergic substances in the body, which block the action of the neurotransmitter acetylcholine. This can happen due to the use of certain medications, such as antidepressants, antihistamines, or muscle relaxants, as well as exposure to some plants or chemicals. Symptoms of anticholinergic toxicity include confusion, dry mouth, dilated pupils, increased heart rate, and difficulty urinating. In severe cases, it can lead to seizures or coma. Treatment typically involves discontinuing the offending agent and may include the use of physostigmine, an antidote that helps restore normal neurotransmitter function.