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Adipex-P Side Effects

Generic name: phentermine

Medically reviewed by Drugs.com. Last updated on Nov 10, 2023.

Note: This document contains side effect information about phentermine. Some dosage forms listed on this page may not apply to the brand name Adipex-P.

Applies to phentermine: oral capsule, oral tablet.

Serious side effects of Adipex-P

Along with its needed effects, phentermine (the active ingredient contained in Adipex-P) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking phentermine:

Rare

Incidence not known

Other side effects of Adipex-P

Some side effects of phentermine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

For Healthcare Professionals

Applies to phentermine: compounding powder, oral capsule, oral capsule extended release, oral tablet, oral tablet disintegrating.

General

The more commonly reported adverse reactions have included palpitations, restlessness, insomnia, and headache.

Cardiovascular

Frequency not reported: Regurgitant cardiac valvular disease, primary pulmonary hypertension, palpitations, tachycardia, elevated blood pressure, precordial pain, ischemic events, angina, myocardial infarction, cardiac failure, cardiac arrest[Ref]

Nervous system

Frequency not reported: Overstimulation, restlessness, nervousness, dizziness, euphoria, dysphoria, tremor, headache, fatigue, cerebrovascular events[Ref]

Psychiatric

Frequency not reported: Insomnia, psychosis, impotence, libido changes, depression, hallucinations[Ref]

Hypersensitivity

Frequency not reported: Urticaria[Ref]

Gastrointestinal

Frequency not reported: Dry mouth, unpleasant taste, diarrhea, constipation, other gastrointestinal disturbances, nausea, vomiting, abdominal cramps[Ref]

Dermatologic

Frequency not reported: Rash[Ref]

Genitourinary

Frequency not reported: Micturition disturbances[Ref]

Other

Frequency not reported: Facial edema[Ref]

Frequently asked questions

References

1. Cerner Multum, Inc. Australian Product Information.

2. Product Information. Phentermine Hydrochloride (phentermine). Teva Pharmaceuticals USA. 2016.

3. Product Information. Adipex-P (phentermine). Teva Pharmaceuticals (formerly Gate Pharmaceuticals). 2016.

4. Product Information. Lomaira (phentermine). KVK-Tech Inc. 2016.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.