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Fastin Side Effects

Generic name: phentermine

Medically reviewed by Drugs.com. Last updated on Nov 10, 2021.

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

For the Consumer

Applies to phentermine: oral phentermine hydrochloride capsules and tablets, oral phentermine resin complex capsules

Side effects include:

Palpitation, tachycardia, increased BP, overstimulation, restlessness, insomnia, tremor, dizziness, headache, euphoria, dysphoria, dryness of the mouth, unpleasant taste, diarrhea, constipation, vomiting, other GI disturbances, urticaria, impotence, changes in libido.

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]

References

1. Cerner Multum, Inc. "Australian Product Information." O 0

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.