GENERIC NAME: phentermine
BRAND NAMES: Adipex-P, Obenix, Suprenza
DISCONTINUED BRANDS: Fastin, Oby-Trim, Obestin-30, OnaMast, Tora, Wilpo
DRUG CLASS AND MECHANISM: Phentermine is a drug that suppresses appetite. Its exact mechanism of action is unknown. It probably decreases appetite by acting on centers in the brain that control appetite. Phentermine is similar to amphetamine. It stimulates the nervous system, elevates blood pressure, and increases heart rate.
PRESCRIBED FOR: Phentermine is combined with diet and exercise for the short-term treatment of obesity in individuals with a body mass index greater than or equal to 30 kg/m2 or greater than or equal to 27 kg/m2 with risk factors for heart disease. Phentermine should not be combined with other weight loss agents. The combination of phentermine and fenfluramine (FEN-PHEN) is associated with serious heart problems. Fenfluramine is no longer available in the United States.
SIDE EFFECTS: Side effects of phentermine include:
- dry mouth,
- an unpleasant taste,
- high blood pressure, and
- fast heart rates (palpitations).
Central nervous system side effects include:
Phentermine, especially when combined with fenfluramine, has been associated with high pressures in the pulmonary arteries (pulmonary hypertension) and defects in heart valves, both serious complications.
Physical and psychological dependence may occur with the long-term use of phentermine. A withdrawal reaction, which includes excessive drowsiness, fatigue, tremors and depression may occur after prolonged use.
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