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: The client has a history of hypertension is not the correct answer. Hypertension is a condition in which the blood pressure is abnormally high, usually above 140/90 mmHg. Propranolol is a beta-blocker that lowers the blood pressure and reduces the workload of the heart. Propranolol is indicated for the treatment of hypertension and angina pectoris, which is a type of chest pain caused by reduced blood flow to the heart. The nurse does not need to report this finding to the provider, as it is consistent with the prescription.

Choice B reason: The client has a history of hypothyroidism is not the correct answer. Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormones, which regulate the metabolism and energy levels. Propranolol can mask some of the signs of hypothyroidism, such as tachycardia, tremors, and anxiety. Propranolol can also interfere with the absorption and conversion of thyroid hormones. The nurse should monitor the client's thyroid function tests and report any abnormal values to the provider, but this finding is not a contraindication to the use of propranolol.

Choice C reason: The client has a history of bronchial asthma is the correct answer. Bronchial asthma is a chronic inflammatory disorder of the airways that causes wheezing, coughing, and shortness of breath. Propranolol is a non-selective beta-blocker that blocks the beta-1 receptors in the heart and the beta-2 receptors in the lungs. Blocking the beta-2 receptors can cause bronchoconstriction, which can worsen the symptoms of asthma and trigger an asthma attack. Propranolol is contraindicated in clients who have bronchial asthma, and the nurse should report this finding to the provider immediately.

Choice D reason: The client has a history of migraine headaches is not the correct answer. Migraine headaches are recurrent episodes of severe and throbbing pain, usually on one side of the head, that can be accompanied by nausea, vomiting, and sensitivity to light and sound. Propranolol is effective in preventing migraine headaches, as it reduces the frequency and severity of the attacks. Propranolol is indicated for the prophylaxis of migraine headaches, and the nurse does not need to report this finding to the provider, as it is consistent with the prescription.

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.