A nurse is caring for a client who has hypertension and asks the nurse about a prescription for propranolol. The nurse should inform the client that this medication is contraindicated in clients who have a history of which of the following conditions?

Choice A reason: Reducing intake of potassium-rich foods is not necessary for clients taking hydrochlorothiazide, as this medication can cause hypokalemia (low potassium levels) due to increased potassium excretion in the urine. Clients may need to increase their intake of potassium-rich foods or take potassium supplements to prevent hypokalemia.

Choice B reason: Avoiding grapefruit juice is not necessary for clients taking hydrochlorothiazide, as this medication does not interact with grapefruit juice. Grapefruit juice can affect the metabolism of some other medications, such as statins, calcium channel blockers, and cyclosporine, by inhibiting the enzyme CYP3A4 in the liver.

Choice C reason: Taking this medication before bedtime is not advisable for clients taking hydrochlorothiazide, as this medication can cause increased urination and nocturia (nighttime urination). Clients should take this medication in the morning or at least 6 hours before bedtime to avoid disrupting their sleep.

Choice D reason: Monitoring for leg cramps is an important instruction for clients taking hydrochlorothiazide, as this medication can cause muscle cramps due to electrolyte imbalances, such as hypokalemia, hyponatremia (low sodium levels), or hypomagnesemia (low magnesium levels). Clients should report any signs of muscle cramps, weakness, or fatigue to their provider.

Choice A reason: Applying a new transdermal patch when chest pain is experienced is not a correct instruction, as it may delay the relief of the pain and increase the risk of adverse effects. Transdermal nitroglycerin is a long-acting form of nitrate that is used for the prevention of angina attacks, not for the treatment of acute episodes. The client should use a short-acting form of nitrate, such as sublingual or spray, for the immediate relief of chest pain.

Choice B reason: Applying the transdermal patch in the morning is a correct instruction, as it helps to maintain a steady level of nitrate in the blood throughout the day and prevent angina attacks. Transdermal nitroglycerin has a duration of action of about 12 to 24 hours, depending on the dose and the individual response. The client should apply the patch in the morning and remove it at night, to allow a nitrate-free interval of at least 8 hours and prevent the development of tolerance.

Choice C reason: Applying the transdermal patch in the same location as the previous patch is not a correct instruction, as it may cause skin irritation and reduce the absorption of the medication. Transdermal nitroglycerin should be applied to a clean, dry, and hairless area of the skin, preferably on the chest, upper arm, or back. The client should rotate the application sites and avoid areas that are exposed to heat, moisture, or friction.

Choice D reason: Applying a new transdermal patch once a week is not a correct instruction, as it may not provide adequate protection against angina attacks and increase the risk of rebound angina. Transdermal nitroglycerin should be applied daily, with a nitrate-free interval of at least 8 hours, to maintain a therapeutic level of nitrate in the blood and prevent the loss of efficacy. The client should follow the prescribed dosing schedule and consult the provider before making any changes.