Nitroglycerin

(ni troh GLIS er in)

Introduced: 1847

Class: Antianginal, nitrates

Prescription: USA: Yes Canada: No

Controlled Drug: USA: No Canada: No

Available as Generic: Yes

Brand Names: Deponit, Nitrol, Nitrolingual Spray, Nitrong SR,

Principal Uses

As a Single Drug Product: Used primarily in the treatment of symptomatic coronary artery disease. The rapid-action forms are used to relieve acute attacks of anginal pain at their onset. The sustained-action forms are used to prevent the development of angina.

How This Drug Works: By direct action on the muscles in blood vessel walls, this drug relaxes and dilates both arteries and veins. Its beneficial effects in the management of angina are due to two mechanisms of action: (1) dilation of narrowed coronary arteries; (2) dilation of veins in the general circulation, with consequent reduction of the volume and pressure of blood entering the heart. The net effects are improved blood supply to the heart muscle and reduced workload for the heart. Both actions reduce the frequency and severity of angina.

Available Dosage Forms and Strengths

Canisters, translingual spray — 13.8 grams (200 doses), 0.4 mg per metered dose Capsules, prolonged-action — 2.5 mg, 2.6 mg, 6.5 mg, 9 mg

Ointment — 2%

Tablets, buccal — 1 mg, 2 mg, 3 mg

Tablets, prolonged-action — 2.6 mg, 6.5 mg, 9 mg

Tablets, sublingual — 0.15 mg, 0.3 mg, 0.4 mg, 0.6 mg

Transdermal systems — 2.5 mg, 5 mg, 7.5 mg, 10 mg, 15 mg (all per 24 hours)

Usual Adult Dosage Range: According to dosage form:

Sublingual spray—1 metered spray (0.4 mg) under tongue/3 to 5 min­utes, up to 3 doses within 15 minutes, to relieve acute angina. To prevent angina, 1 spray taken 5 to 10 minutes before exertion.

Sublingual tablets—0.15 to 0.6 mg dissolved under tongue at 5-minute intervals to relieve acute angina.

Prolonged-action tablets—1.3 to 6.5 mg at 8- to 12-hour intervals to pre­vent angina.

Prolonged-action capsules—2.5 to 9 mg at 8- to 12-hour intervals to prevent angina.

Ointment—2.5 to 5 cm (1 to 2 inches, 15 to 30 mg) applied in a thin, even layer of uniform size to hairless skin at 3- to 4-hour intervals to prevent angina.

Buccal tablets—1 to 2 mg/4 to 5 hours placed between cheek and gum.

Transdermal patches—5-sq.-cm to 30-sq.-cm patch applied to hairless skin once/24 hours to prevent angina. Note: Actual dosage and administration schedule must be determined by the physician for each patient individually.

Dosing Instructions: Dosage forms to be swallowed are best taken when stomach is empty (1 hour before or 2 hours after eating) to obtain maximal blood levels. Tablets should not be crushed for administration. Capsules may be opened, but the contents should not be crushed or chewed before swallowing.

Usual Duration of Use: Continual use on a regular schedule for 3 to 5 days is usually necessary to determine this drug's effectiveness in preventing and relieving acute anginal attacks. Individual dosage adjustments will be necessary for optimal results. Long-term use (months to years) re­quires supervision and periodic evaluation by your physician. Consult your physician on a regular basis.

This Drug Should Not Be Taken If

• you have had an allergic reaction to it previously.

• you are severely anemic.

• you have closed-angle glaucoma (inadequately treated).