Phentermine is the most widely-prescribed weight-loss medication in the United States. It first received FDA approval in 1959 as an appetite suppressant for the short-term management of obesity. History. Fenfluramine as a single drug was first introduced in the 1970s, but was not popular because it only temporarily reduced weight. A 1984 study found a weight loss of 7.5 kg on average in 24 weeks, as compared to 4.4 kg under placebo. It sold modestly until the 1990s, when it was combined with phentermine and heavily marketed. A similar. Phentermine is a prescription appetite suppressant used for the short-term treatment of obesity [1, 2]. It is utilized in combination with behavioral changes such as eating a healthier diet and exercising regularly to promote weight loss. Phentermine is taken once daily, in the morning, by mouth in the form of a tablet pill. Phentermine is only available by prescription. Weight Loss MD only uses pharmaceutical grade medication from manufactures in the United States. For Obesity: I'm on my 5th month of Phentermine for weight loss. I was originally prescribed it for 3 months, but since I'm doing well with NO side effects, my doc gave me the option of taking it for up to 6 months. User Reviews for Phentermine (Page 2) Also known as: Adipex-P, Lomaira, Suprenza. The following information is NOT intended to endorse drugs or recommend therapy. ‡Qsymia was studied in 2 large trials supporting FDA approval that involved 3754 patients whose BMI was 27 kg/m 2 or greater. Patients were randomized to placebo, phentermine 3.75 mg/topiramate 23 mg, phentermine 7.5 mg/topiramate 46 mg, or phentermine 15 mg/topiramate 92 mg. INDICATIONS. ADIPEX-P ® is indicated as a short-term (a few weeks) adjunct in a regimen of weight reduction based on exercise, behavioral modification and caloric restriction in the management of exogenous obesity for patients with an initial body mass index greater than or equal to 30 kg/m 2, or greater than or equal to 27 kg/m 2 in the. Phentermine is a prescription weight-loss drug. Most doctors agree that phentermine works by suppressing the appetite and upregulating the metabolism, though the specific pathways are not fully understood. How to use Phentermine HCL. Take this medication by mouth as directed by your doctor, usually once a day, 1 hour before breakfast or 1 to 2 hours after breakfast.