Which organ is primarily responsible for excretion of a medication?

Choice A reason: “This medication should be taken after eating to reduce nausea.” is not a correct statement that demonstrates understanding about ondansetron. Ondansetron is a medication that prevents nausea and vomiting by blocking the action of serotonin, a chemical that stimulates the vomiting center in the brain. Ondansetron can be taken with or without food, and it does not affect the digestion or absorption of food. Ondansetron is usually taken before the start of chemotherapy, radiation, or surgery, which are the common causes of nausea and vomiting.

Choice B reason: “This medication should not be taken with starfruit.” is not a correct statement that demonstrates understanding about ondansetron. Ondansetron is a medication that prevents nausea and vomiting by blocking the action of serotonin, a chemical that stimulates the vomiting center in the brain. Ondansetron does not interact with starfruit, which is a tropical fruit that contains substances that can inhibit the enzyme CYP3A4, which is involved in the metabolism of many drugs. Ondansetron is mainly metabolized by another enzyme, CYP1A2, and it has a low potential for drug interactions¹.

Choice C reason: “This medication may make me tired and confused.” is a correct statement that demonstrates understanding about ondansetron. Ondansetron is a medication that prevents nausea and vomiting by blocking the action of serotonin, a chemical that stimulates the vomiting center in the brain. Ondansetron can also cross the blood brain barrier and affect other serotonin receptors in the brain, which are involved in regulating mood, cognition, and sleep. Ondansetron can cause side effects such as fatigue, drowsiness, headache, and confusion, which can impair the mental alertness and performance of the client. The client should be advised to avoid driving, operating machinery, or doing other tasks that require attention after taking ondansetron.

Choice D reason: “This medication may cause rebound nausea.” is not a correct statement that demonstrates understanding about ondansetron. Ondansetron is a medication that prevents nausea and vomiting by blocking the action of serotonin, a chemical that stimulates the vomiting center in the brain. Ondansetron does not cause rebound nausea, which is a condition of nausea that occurs after the discontinuation of a medication that suppresses nausea. Ondansetron is not a medication that suppresses nausea, but rather prevents it by blocking the stimulation of the vomiting center. Ondansetron does not cause dependence or withdrawal symptoms, and it can be stopped without causing rebound nausea.

Choice A reason: This is incorrect. Lisinopril is an angiotensin converting enzyme (ACE) inhibitor that lowers blood pressure and reduces the workload of the heart. It does not have a diuretic effect, meaning it does not increase urination.
Choice B reason: This is correct. Lisinopril can cause orthostatic hypotension, which is a sudden drop in blood pressure when changing positions. This can lead to dizziness, fainting, or falls. To prevent this, the nurse should instruct the client to rise slowly from sitting or lying positions and to avoid sudden movements.
Choice C reason: This is incorrect. Lisinopril can be taken with or without food. Taking it on an empty stomach does not improve its effectiveness or reduce its side effects.
Choice D reason: This is incorrect. Lisinopril does not cause weight gain due to fluid retention. In fact, it can help reduce edema, which is swelling caused by excess fluid in the body.