Nitrates are antianginals. They relax vascular smooth muscle with a resultant decrease in venous return and decrease in arterial blood pressure, which reduces left ventricular workload and decreases myocardial oxygen consumption, relieving the pain of angina.

Indications

Treatment of acute angina (sublingual, translingual, inhalant preparations)

Prophylaxis of angina (oral sustained release, sublingual, topical, transdermal, translingual, transmucosal preparations)

Treatment of angina unresponsive to recommended doses of organic nitrates or betablockers (IV preparations)

Management of perioperative hypertension, heart failure associated with acute MI (IV preparations)

Produce controlled hypotension during surgery (IV preparations)Unlabeled uses: Reduction of cardiac workload in acute MI and in heart failure (sublingual,topical); diffuse esophageal spasm without reflux

Contraindications and cautions

Contraindicated with allergy to nitrates, angle-closure glaucoma, severe anemia, early MI, head trauma, cerebral hemorrhage, cardiomyopathy, concommitant use with phosphodiesterase type 5 (PDE5) inhibitors, pregnancy, or lactation.

Use cautiously with hepatic or renal disease, hypotension or hypovolemia, increased in- tracranial pressure, constrictive pericardi- tis, pericardial tamponade, low ventricular filling pressure or low pulmonary capillary wedge pressure (PCWP).

Adverse effects

CNS: Headache,apprehension, restlessness, weakness, vertigo, dizziness, faintness

CV: Tachycardia, retrosternal discomfort, palpitations, hypotension, syncope, collapse, orthostatic hypotension, angina

Dermatologic: Rash, exfoliative dermatitis, cutaneous vasodilation with flushing, pallor, perspiration, cold sweat, contact dermatitis (transdermal preparations), topical allergic reactions (topical nitroglycerin ointment)

GI: Nausea, vomiting, incontinence of urine and feces, abdominal pain

Local: Local burning sensation at the point of dissolution (sublingual)

Other: Ethanol intoxication with high dose IV use (alcohol in diluent)

Interactions

Drug-drug

Increased risk of hypertension and decreased antianginal effect with ergot alkaloids

Decreased pharmacologic effects of heparin

Risk of orthostatic hypotension with calcium channel blockers

Profound hypotension with PDE5 inhibitors

Drug-lab test

False report of decreased serum cholesterol if done by the Zlatkis-Zak color reaction