Phentermine Vs. Ephedra

Phentermine and ephedra are appetite suppressants, but the U.S. Food and Drug Administration banned the sale of products containing ephedra in 2004. Also, phentermine is one of the ingredients of the banned fen-phen combination. But medical researchers concluded that phentermine was not the problem ingredient in fen-phen, so phentermine is still prescribed without the banned ingredient fenfluramine.

Ephedra Problems

Ephedra or ma huang has been used in herbal medicine but is not safe especially when combined with caffeine, according to the National Center for Complementary and Alternative Medicine. Ephedra and ephedrine alkaloids can increase a dieter's blood pressure to dangerously high levels; the drug was also linked to fatal heart attacks and strokes. Thus, the FDA banned sales of any supplement containing ephedra or its alkaloids in 2004.

Fen-Phen Ban

Phentermine, part of the banned fen-phen combo, has been prescribed as an appetite suppressant since 1959, according to the Mayo Clinic. In 1997, researchers with the Mayo Clinic and the FDA discovered that fenfluramine was responsible for sometimes-fatal heart valve and lung damage in patients. They declared phentermine relatively safe for use, and that appetite suppressant is the most commonly prescribed diet pill in the United States.

Phentermine Basics

Your doctor may prescribe an instant-release tablet form of phentermine to take before meals or an extended-release capsule that works to suppress your appetite all day, according to PubMed Health. Phentermine is available in its generic form or under the brand names Adipex-P, Atti Plex P, Ionamin, Kraftobese, Panshape M, Phentercot, Phentride, Pro-Fast, Raphtre, Supramine, Tara-8, Teramine and Termene. Most doctors prescribe phentermine for three to six weeks and you should not use it for more than 12 weeks at a time due to its potential for addiction.

Contraindictions and Side Effects

You should not take phentermine if you have a history of drug or alcohol abuse, are pregnant, planning to get pregnant, nursing a baby or have high blood pressure, warns PubMed Health. You may experience side effects such as dry mouth, an unpleasant taste in your mouth, nausea, vomiting or diarrhea. If you experience itching, hives, difficulty breathing, difficulty exercising, heart palpitations, increased blood pressure, chest pain, dizziness, swelling in your legs and ankles or severe insomnia, seek immediate medical aid. Alcohol can worsen phentermine side effects, so limit your drinking while on this appetite suppressant.