NitroMist® should not be used in patients who are using phosphodiesterase type 5 inhibitors, such as those used for the treatment of erectile dysfunction, which have been shown to potentiate the hypotensive effects of organic nitrates. NitroMist® should not be used in patients with severe anemia, in patients with increased intracranial pressure, and in patients with a history of hypersensitivity to this or other nitrates or nitrites. Skin reactions consistent with hypersensitivity have been observed with organic nitrates. NitroMist® should be used with caution if patients have low systolic blood pressure, are undergoing diuretic therapy, or are undergoing tissue-type plasminogen activator therapy.
Co-administration of aspirin and nitroglycerin has been reported to increase nitroglycerin levels and intravenous nitroglycerin reduces the anticoagulant effect of heparin, so activated partial thromboplastin times should be monitored. Oral administration of nitroglycerin increases bioavailability of ergotamine, so concomitant use of ergotamine and related drugs should be avoided. Excessive use may lead to the development of tolerance. Severe hypotension, particularly with upright posture, may occur even with small doses of nitroglycerin.
Hypotension induced by nitroglycerin may be accompanied by paradoxical bradycardia and increased angina pectoris. The benefits of NitroMist® in patients with acute myocardial infarction or congestive heart failure have not been established. Nitrate therapy may aggravate the angina caused by hypertrophic cardiomyopathy. Nitroglycerin produces dose-related headaches, which may be severe. Tolerance to headaches occurs. The most common adverse reactions are headache, flushing, hypotension and syncope.