In a cholinergic crisis in a patient with myasthenia gravis, which medication should the nurse plan to administer?

In the context of a cholinergic crisis in a patient with myasthenia gravis, atropine is the appropriate medication to administer. A cholinergic crisis occurs when there is an excess of acetylcholine at the neuromuscular junction, often due to excessive dosing of cholinergic medications like pyridostigmine. This can lead to symptoms such as muscle weakness, salivation, lacrimation, urination, diarrhea, gastrointestinal distress, and respiratory muscle paralysis.

Atropine is an anticholinergic agent that works by blocking the effects of acetylcholine on muscarinic receptors. In a cholinergic crisis, atropine can help mitigate the overstimulation caused by excess acetylcholine, particularly alleviating symptoms like increased salivation and bronchial secretions.

Other medications listed are not effective in managing the symptoms of a cholinergic crisis. For instance, potassium iodide does not interact with the cholinergic system, glucagon primarily addresses hypoglycemia or beta-blocker overdose, and protamine is used to reverse heparin's effects but has no role in cholinergic crises. Hence, atropine is essential in treating the cholinergic toxicity associated with myasthenia gravis