Question

"Patient: 39-year-old woman

Chief complaint: Please excuse my sunglasses. I had an eye doctor appointment before my dentist appointment, and the optometrist put in drops to dilate my eyes.
What is most likely the mechanism of action of the eye drops administered to your patient
a. it inhibited the parasympathetic innervation of the muscles in the iris.
b. It induced the parasympathetic innervation of the muscles in the iris.
c. It inhibited the sympathetic innervation of the muscles in the iris"

Answer 1

The eye drops administered to the patient likely inhibited the parasympathetic innervation of the muscles in the iris, resulting in pupillary dilation.

Step-by-step explanation:

The mechanism of action of the eye drops administered to the patient is that they inhibited the parasympathetic innervation of the muscles in the iris.

Normally, the parasympathetic system releases acetylcholine to stimulate the circular iris muscles, causing constriction of the pupil. However, the eye drops likely contained an adrenergic receptor antagonist or blocker, which prevents the release of acetylcholine, thus inhibiting the constriction of the pupil.

By inhibiting the parasympathetic innervation, the eye drops cause pupillary dilation, allowing more light to enter the eye.