A patient has been newly prescribed gentamicin 120mg, IM, once.

After reviewing the patient’s home medication list, which medication should the nurse be most concerned about?

Choice A rationale
Hyponatremia, or low sodium levels, is not typically associated with the use of milk of magnesia. Milk of magnesia works by drawing water into the intestines, which can help to soften the stool and stimulate bowel movements. While it can affect fluid balance, it does not directly affect sodium levels in the body.
Choice B rationale
This choice is correct. Milk of magnesia contains magnesium and can lead to hypermagnesemia, or high magnesium levels, if taken in excess or if the client has impaired kidney function. Hypermagnesemia can cause various symptoms, including nausea, vomiting, low blood pressure, and in severe cases, heart arrhythmias and cardiac arrest.
Choice C rationale
Hypokalemia, or low potassium levels, is not typically associated with the use of milk of magnesia. While milk of magnesia can affect fluid and electrolyte balance, it does not directly affect potassium levels in the body.
Choice D rationale
Hypercalcemia, or high calcium levels, is not typically associated with the use of milk of magnesia. Milk of magnesia does not contain calcium, so it would not contribute to an increase in calcium levels in the body.

Choice A rationale
Administering ondansetron when the client feels nauseous or vomits is not the most effective use of the medication. The goal is to prevent nausea and vomiting from occurring in the first place.
Choice B rationale
Administering ondansetron immediately after chemotherapy is complete may not provide the most effective prevention of nausea and vomiting. The medication needs time to work and should ideally be administered before chemotherapy begins.
Choice C rationale
The optimal time to administer ondansetron is 30 minutes prior to starting chemotherapy. This allows the medication to start working before the chemotherapy drugs that cause nausea and vomiting are administered.
Choice D rationale
While it’s important to respond to a client’s requests, waiting until the client requests the ondansetron may not prevent the onset of nausea and vomiting. It’s more effective to administer the medication proactively.