phentermine (Adipex-P, Obenix, Suprenza)

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

  • Medical and Pharmacy Editor: Charles Patrick Davis, MD, PhD
    Charles Patrick Davis, MD, PhD

    Charles Patrick Davis, MD, PhD

    Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

Habits That Can Help You Lose Weight Slideshow

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:

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.

Medically Reviewed by a Doctor on 9/18/2015
FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

See more info: phentermine on RxList
RxList Logo

Need help identifying pills and medications?

Use the pill identifier tool on RxList.

Subscribe to MedicineNet's Weight Loss/Healthy Living Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Health Solutions From Our Sponsors