A nurse is reviewing laboratory results of a client who has atrial fibrillation and is taking warfarin. For which of the following results should the nurse notify the provider?

Choice A reason: This is not a problem for a client who has hypertension and a new prescription for metoprolol, as metoprolol is a beta-blocker that can reduce the workload of the heart and improve the symptoms of heart failure.

Choice B reason: This is not a problem for a client who has hypertension and a new prescription for metoprolol, as metoprolol does not have any significant interactions with antibiotics or other medications used to treat pneumonia.

Choice C reason: This is a problem for a client who has hypertension and a new prescription for metoprolol, as tadalafil is a phosphodiesterase-5 inhibitor that can lower the blood pressure and cause hypotension when taken with metoprolol. The nurse should investigate further and notify the provider of the potential interaction.

Choice D reason: This is not a problem for a client who has hypertension and a new prescription for metoprolol, as metoprolol does not affect the blood glucose levels or the management of diabetes.

Choice A reason: Ototoxicity is not a severe reaction to propranolol, but it may occur with some other medications, such as aminoglycosides, loop diuretics, or salicylates. Ototoxicity may damage the inner ear or the auditory nerve and cause hearing loss, tinnitus, or vertigo. The nurse should assess the client's medication history and monitor the client's hearing function.

Choice B reason: Hypokalemia is not a severe reaction to propranolol, but it may occur with some other medications, such as thiazide diuretics, corticosteroids, or insulin. Hypokalemia may cause muscle weakness, cramps, arrhythmias, or cardiac arrest. The nurse should advise the client to eat foods rich in potassium, such as bananas, oranges, or potatoes, and to have regular blood tests to check the electrolyte levels.

Choice C reason: Tachycardia is not a severe reaction to propranolol, but it may be a sign of overdose, withdrawal, or rebound effect. Propranolol is a beta-blocker that lowers the heart rate and blood pressure by blocking the effects of epinephrine and norepinephrine. Propranolol may cause bradycardia, not tachycardia, as a side effect. The nurse should monitor the client's vital signs and advise the client to take the medication as prescribed and not to stop it abruptly.

Choice D reason: Postural hypotension is a severe reaction to propranolol, as it may cause dizziness, fainting, or falls. Postural hypotension occurs when the blood pressure drops significantly when the client changes position, such as from lying to sitting or standing. Propranolol may cause postural hypotension by reducing the vascular tone and the cardiac output. The nurse should instruct the client to change position slowly and to report any symptoms of postural hypotension to the provider.