Should I discontinue (DC) hydralazine in a patient who developed flushing and chest tightness after administration?

From the Guidelines

Yes, you should discontinue hydralazine in this patient who developed flushing and chest tightness after administration, as these symptoms suggest a possible hypersensitivity reaction. Immediately stop the medication, monitor the patient's vital signs, and assess for additional symptoms such as rash, wheezing, or hypotension that could indicate a more severe reaction.

Reasons for Discontinuation

• The patient's symptoms of flushing and chest tightness after hydralazine administration suggest a possible hypersensitivity reaction, which is a contraindication for continued use of the medication 1.
• Hydralazine can cause direct vasodilation leading to flushing, but when accompanied by chest tightness, this suggests an immune-mediated reaction rather than just the expected pharmacologic effect.
• The medication should be discontinued to prevent further adverse reactions and potential complications.

Next Steps

• Document this reaction clearly in the patient's chart and add hydralazine to their allergy list.
• After discontinuation, consult with the patient's primary physician to select an alternative antihypertensive medication from a different drug class, such as an ACE inhibitor, ARB, calcium channel blocker, or beta-blocker 1.
• The patient should be counseled to avoid hydralazine in the future and to inform all healthcare providers about this reaction.

Key Considerations

• The selection of an antihypertensive agent should be based on the drug’s pharmacology, pathophysiological factors underlying the patient’s hypertension, degree of progression of target organ damage, the desirable rate of BP decline, and the presence of comorbidities.
• Continuous infusion of short-acting titratable antihypertensive agents is often preferable to prevent further target organ damage in hypertensive emergencies.

From the FDA Drug Label

Adverse reactions with hydralazine hydrochloride are usually reversible when dosage is reduced. However, in some cases it may be necessary to discontinue the drug. The patient developed flushing and chest tightness after administration of hydralazine, which may be indicative of an adverse reaction.

• Discontinuation of hydralazine should be considered in this case, as the drug label suggests that adverse reactions are usually reversible when dosage is reduced, but may require discontinuation in some cases 2.
• It is also important to note that the drug label does not provide specific guidance on the management of flushing and chest tightness, but it does suggest that the drug should be used with caution in patients with suspected coronary artery disease, as it may cause anginal attacks and ECG changes of myocardial ischemia 2.
• Therefore, the decision to discontinue hydralazine should be made on a case-by-case basis, taking into account the patient's individual clinical situation and medical history.

From the Research

Patient Reaction to Hydralazine

The patient in question has developed flushing and chest tightness after administration of hydralazine. This reaction could be indicative of an adverse response to the medication.

Possible Causes and Considerations

• The patient's symptoms may be related to the vasodilatory effects of hydralazine, which can cause a decrease in blood pressure and lead to reflex tachycardia 3.
• Hydralazine has been known to cause serious adverse reactions, including hypotension, renal insufficiency, and decreased systemic arterial oxygen saturation 3.
• The patient's reaction may also be related to their individual acetylator phenotype, as slow acetylators are more likely to experience side effects from hydralazine 4.
• It is also possible that the patient is experiencing a rare but severe cutaneous presentation of hydralazine-induced ANCA vasculitis, although this would typically be accompanied by other symptoms such as renal or pulmonary involvement 5.

Consideration of Discontinuation

• Given the patient's symptoms, it may be necessary to discontinue hydralazine to prevent further adverse reactions.
• The decision to discontinue hydralazine should be made on a case-by-case basis, taking into account the patient's individual response to the medication and their underlying medical condition.
• Alternative treatments may be considered, such as other vasodilators or antihypertensive medications, depending on the patient's specific needs and medical history.