The telephone triage nurse receives a call from a patient asking for a prescription for a narcotic to manage his surgical pain.
The nurse explains that narcotic prescriptions must be written and cannot be called in to the pharmacy.
The patient says, “Why are narcotics so difficult to get a prescription for?” What is the nurse’s best response?

Choice A rationale

Anticholinergic drugs do not cause pupil restriction; they relax the muscles around the eye, leading to dilation.

Choice B rationale

Decreased lacrimal secretions are a secondary effect of anticholinergics and not their primary purpose in ophthalmology.

Choice C rationale

Anticholinergics cause pupil dilation (mydriasis) by relaxing the muscles that constrict the pupil, allowing for a better examination of the eye's interior.

Choice D rationale

Sedation is not a primary effect of anticholinergics used in ophthalmology.

Choice A rationale

This choice is incorrect. Cholinergic agonists primarily affect acetylcholine receptors, not GABA receptors. GABA receptors are involved in the inhibitory neurotransmission in the central nervous system and are the target of different drug classes, such as benzodiazepines and barbiturates, which are not related to cholinergic agonists.

Choice B rationale

This choice is incorrect. Cholinergic agonists do not decrease norepinephrine activity. Norepinephrine is a neurotransmitter involved in the sympathetic nervous system response, which is different from the cholinergic system. Drugs that decrease norepinephrine activity would have a different mechanism of action, such as adrenergic antagonists.

Choice C rationale

This choice is incorrect. The primary action of cholinergic agonists is not to increase dopamine activity. Dopamine is another neurotransmitter involved in various brain functions, including reward and motor control. Cholinergic agonists specifically target acetylcholine receptors, enhancing their activity, which is not related to dopamine receptors.

Choice D rationale

This choice is correct. Cholinergic agonists increase the activity of acetylcholine receptor sites throughout the body. These drugs mimic the action of acetylcholine, a neurotransmitter that plays a key role in the parasympathetic nervous system, which regulates functions such as muscle contraction, gland secretion, and heart rate. Enhancing acetylcholine activity helps in conditions like myasthenia gravis and certain types of glaucoma.