Overview
DESCRIPTION Mecamylamine HCl is a potent, oral antihypertension agent and ganglion blocker, and is a secondary amine. It is N,2,3,3-tetramethyl-bicyclo [2.2.1] heptan- 2 -amine hydrochloride. Its empirical formula is C 11 H 21 N • HCl and its structural formula is: It is a white, odorless, or practically odorless, crystalline powder, is highly stable, soluble in water and has a molecular weight...
Mechanism of Action
CLINICAL PHARMACOLOGY Mecamylamine HCl reduces blood pressure in both normotensive and hypertensive individuals. It has a gradual onset of action (1/2 to 2 hours) and a long-lasting effect (usually 6 to 12 hours or more). A small oral dosage often produces a smooth and predictable reduction of blood pressure. Although this antihypertensive effect is predominantly orthostatic, the supine blood pressure is also significantly reduced. Pharmacokinetics and Metabolism Mecamylamine HCl is almost completely absorbed from the gastrointestinal tract, resulting in consistent lowering of blood pressure in most patients with hypertensive cardiovascular disease. Mecamylamine HCl is excreted slowly in the urine in the unchanged form.
Indications
- INDICATIONS AND USAGE For the management of moderately severe to severe essential hypertension and in uncomplicated cases of malignant hypertension.
Common Doses
- 2.5 mg
- 25 mg
Dosage
DOSAGE AND ADMINISTRATION Therapy is usually started with one 2.5 mg tablet of Mecamylamine HCl twice a day. This initial dosage should be modified by increments of one 2.5 mg tablet at intervals of not less than 2 days until the desired blood pressure response occurs (the criterion being a dosage just under that which causes signs of mild postural hypotension). The average total daily dosage of Mecamylamine HCl is 25 mg, usually in three divided doses. However, as little as 2.5 mg daily may be sufficient to control hypertension in some patients.
Contraindications
- CONTRAINDICATIONS Mecamylamine HCl should not be used in mild, moderate, labile hypertension and may prove unsuitable in uncooperative patients. It is contraindicated in coronary insufficiency or recent myocardial infarction. Mecamylamine HCl should be given with great discretion, if at all, when renal insufficiency is manifested by a rising or elevated BUN. The drug is contraindicated in uremia. Patients receiving antibiotics and sulfonamides should generally not be treated with ganglion blockers.
Side Effects
- ADVERSE REACTIONS The following adverse reactions have been reported and within each category are listed in order of decreasing severity. Gastrointestinal: Ileus, constipation (sometimes preceded by small, frequent liquid stools), vomiting, nausea, anorexia, glossitis and dryness of mouth. Cardiovascular: Orthostatic dizziness and syncope, postural hypotension. Nervous System/Psychiatric: Convulsions, choreiform movements, mental aberrations, tremor, and paresthesias (see WARNINGS ). Respiratory: Interstitial pulmonary edema and fibrosis.
Interactions
- Drug Interactions Patients receiving antibiotics and sulfonamides generally should not be treated with ganglion blockers. The action of Mecamylamine HCl may be potentiated by anesthesia, other antihypertensive drugs and alcohol.