The nurse is caring for a client with neurogenic diabetes insipidus and administers what drug to treat the condition.

Octreotide is a synthetic analog of somatostatin, a hormone that inhibits the secretion of growth hormone, insulin, glucagon, and other hormones. Octreotide can cause gastrointestinal side effects such as abdominal pain, diarrhea, constipation, nausea, vomiting, and flatulence. These side effects are more common and severe with the oral route than with the injectable route.

Choice B is wrong because tinnitus, or ringing in the ears, is not a common or serious side effect of octreotide.

Choice C is wrong because alteration in consciousness is not a common or serious side effect of octreotide.

However, octreotide can affect blood glucose levels and cause hypoglycemia or hyperglycemia, which can lead to confusion, dizziness, fainting, seizures, or coma in severe cases.

Choice D is wrong because changes in vision are not a common or serious side effect of octreotide.

However, octreotide can cause rare but serious eye problems such as blurred vision, double vision, eye pain, or blindness due to optic nerve damage or retinal detachment.

These eye problems require immediate medical attention.

Normal ranges for blood glucose are 70 to 100 mg/dL (3.9 to 5.6 mmol/L) for fasting and less than 140 mg/dL (7.8 mmol/L) for postprandial.

Oxygen cannot diffuse rapidly across the membrane to tissues in the eye. This is because diabetic retinopathy is a condition that occurs when high blood sugar levels damage the tiny blood vessels that nourish the retina, the light-sensitive tissue at the back of the eye. As a result, the retina becomes ischemic (lacking oxygen) and tries to grow new blood vessels that are fragile and leaky.

Choice A is wrong because inability of cells in the eye to reproduce is not a cause of diabetic retinopathy.

The retina has a high metabolic rate and needs a constant supply of oxygen and nutrients to function properly.

Choice B is wrong because increase of aqueous humor in the eye is not a cause of diabetic retinopathy.

Aqueous humor is the clear fluid that fills the front part of the eye, not the retina.

An increase of aqueous humor can cause glaucoma, which is a different eye disorder that affects the optic nerve.

Choice C is wrong because decrease of nerve innervations throughout the eye is not a cause of diabetic retinopathy.

Nerve innervations are the connections between nerves and other tissues, such as muscles or glands.

Diabetic retinopathy affects the blood vessels, not the nerves, of the retina.