Obesity is an illness which is harder to take care of than many cancers. Doctors and patients have been buying a medicinal approach coupled with proper nutrition and regular exercises to cope with chronic obesity. One of the most popular drug for the goal is phentermine.

Once broadly praised as a "wonder drug", phentermine still boasts as the most commonly recommended appetite suppressant in the US, one of the reason being their cheaper cost compared to other similar drugs.

Phentermine enhances the levels of several neurotransmitters including dopamine and norepinephrine affecting blood flow, heartbeat, and reactivity to stress. Can make people eat more rapidly but for eat less. Another urge for food suppressant, fenfluramine, acts on a different neurotransmitter, serotonin. Serotonin is involved with handling mood and reduces the feelings of agitation associated with hunger.

Phentermine is a generic name, which is sold under various brandnames including Ionamin, Adpex-P, Fastin, etc. Phentermine first became available for consumers in the late 50s, and later modified as Phentermine Hydrochloride (HCl) in the 70s.

Phentermine became popular again in the 90s as 'cocktail', Fen-Phen. Within 1992, Dr. Weintraub from University of Rochester Institution of drugs and Dentistry posted a paper with a study that Fen-Phen works more effectively than diet or exercise in persistent obese cases. Fen-Phen became an overnight sensation.

Whilst phentermine and fenfluramine are both approved by FOOD AND DRUG ADMINISTRATION separately, their mixture, 'Fen-Phen' never was, and their prescription by doctors was considered "off-label".

Dexfen-Phen is another mixture including phentermine. In this case, the other ingredient is dexfenfluramine or redux. Dexfenfluramine was also used being an appetite suppressant. Dexfen-Phen again followed the suit, and became widely popular.

In 1997, Mayo Clinic reported twenty four cases of heart control device disease in the patients who had taken fen-phen beverage. Further findings suggested fenfluramine and dexfenfluramine may be related to heart device disorder, and accordingly, FOOD AND DRUG ADMINISTRATION (FDA) issued a public health advisory and requested drug manufacturers to voluntarily pull away fenfluramine and dexfenfluramine.

Unlike fenfluramine and dexfenfluramine, phentermine was not removed the market. Phentermine is again used in various beverage forms. It was necessary since phentermine's appetite suppressing effect decreases rather swiftly over time.

Among the new cocktail involving phentermine is "Phen-Pro", phentermine plus prozac, a popular antidepressants. Phen-pro cocktail makes phentermine work longer and has no considerable psychological effect.