A nurse is caring for a client who has developed agranulocytosis as a result of taking propylthiouracil to treat hyperthyroidism. The nurse should understand that this client is at increased risk for which of the following conditions?

Choice A reason: Vitamin K is the antidote for warfarin, not heparin. Vitamin K reverses the effects of warfarin by increasing the synthesis of clotting factors in the liver.

Choice B reason: Glucagon is the antidote for insulin, not heparin. Glucagon increases the blood glucose level by stimulating the breakdown of glycogen in the liver.

Choice C reason: Protamine is the antidote for heparin, not vitamin K or glucagon. Protamine neutralizes the effects of heparin by binding to it and forming a stable complex.

Choice D reason: Iron is not an antidote for any anticoagulant. Iron is a mineral that is essential for the production of hemoglobin and red blood cells.

Choice A reason: Expecting to gain weight while taking this medication is not a correct instruction, as it may discourage the client from adhering to the treatment and may worsen the hypertension. Captopril is an angiotensin-converting enzyme (ACE) inhibitor that lowers the blood pressure by preventing the formation of angiotensin II, a potent vasoconstrictor. Captopril does not cause significant weight gain, but it may cause fluid retention or edema in some cases. The nurse should advise the client to monitor the weight daily and report any sudden or excessive increase to the provider.

Choice B reason: Not using salt substitutes while taking this medication is a correct instruction, as it may prevent the risk of hyperkalemia, a potentially life-threatening condition. Captopril may increase the potassium level in the blood by reducing the secretion of aldosterone, a hormone that regulates the sodium and potassium balance. Salt substitutes may contain potassium chloride, which may further elevate the potassium level. The nurse should advise the client to avoid salt substitutes and high-potassium foods, such as bananas, oranges, or tomatoes, and to have regular blood tests to check the electrolyte levels.

Choice C reason: Counting the pulse rate before taking the medication is not a necessary instruction, as it may not reflect the effect of the medication on the blood pressure. Captopril does not affect the heart rate significantly, but it may lower the blood pressure too much, especially in the first few weeks of treatment or after a dose increase. This may cause hypotension, dizziness, or fainting. The nurse should advise the client to monitor the blood pressure regularly and report any symptoms of hypotension to the provider.

Choice D reason: Taking the medication with food is not a correct instruction, as it may reduce the absorption and effectiveness of the medication. Captopril should be taken on an empty stomach, at least one hour before or two hours after a meal, to ensure optimal bioavailability. The nurse should advise the client to take the medication at the same time every day and to avoid skipping or doubling the doses.