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
The more commonly reported adverse reactions have included palpitations, restlessness, insomnia, and headache.
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]
Frequency not reported: Urticaria[Ref]
Frequency not reported: Rash[Ref]
Frequency not reported: Micturition disturbances[Ref]
More about Fastin (phentermine)
- Drug interactions
- Dosage information
- During pregnancy or Breastfeeding
- Reviews (81)
- Drug images
- Drug class: anorexiants
Related treatment guides
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):
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.