Is Phentermine Appetite Suppressants Approved by the FDA Right for You?
Phentermine appetite suppressants have been approved for weight loss by the FDA since 1959. This is a very long time for any medication. The fact that its has been on the market for more than 65 years and over 50 million prescriptions have been written for it in the US alone tells us much about the safety and efficacy of the medication. I prescribed phentermine and the other FDA appetite suppressors to many overweight patients based on their medical history, metabolic and weight loss needs.When given to the appropriate patient there is steady, predictable weight loss of 2-3 lbs per week(sometimes greater depending upon the age, gender and starting weight of the patient) without any significant side effects. In fact the only side effects I see are dry mouth and a little bit of insomnia. The latter can be eliminated by taking the medications earlier in the day and avoiding caffeine after lunch.
Phentermine: Phendimetrazine Diethylpropion Tenuate®
Phentermine appetite supprssors include brand names of Fastin, Ionamin and Adipex. They are among the first drugs approved as an appetite suppressor (1959). Phentermine is sold under a variety of brand names including Ionamin® and Adipex-P® as well as under its generic name. Phentermine and its cousins Phendimetrazine and Diethylpropion are all sympathomimetic amines. They are known as an “anorectic” or “anorexigenic” drugs. Phentermine, phendimetrazine and diethylprorion have very little effect on blood pressure or heart rate. In low doses, most people experience virtually no effect on blood pressure, heart and even sleep. More than 100 extensive studies have been recently reported.
According to the National Library of Medicine, phentermine’s primary mode of action is that it increases the body’s release of catecholamines, specifically, epinephrine and norepinephrine, and possibly dopamine, as well. These catecholamines cause a decrease in appetite and an increase in energy expenditure by their influence on a variety of neurotransmitters and neuropeptides throughout the hypothalmus Quite simply, when you are taking phentermine, you tend to feel less hungry but more energetic and alert. Increased energy expenditure will burn more calories. Weight loss results from a combination of these influences.
Phentermine Appetite suppressants: Three Recent Studies Show Efficacy & Minimal Side Effects
Phentermine Appetite Sup[pressors: Weight Loss Study in UK:
Phentermine as an appetite suppressor was found effective in a British Study that compared it to a placebo over months. This study included three groups of 36 women each, two of which were given phentermine to augment their weight loss efforts. One group was given 15 mg per day continuously, and the other was given the same dose but only every other month. Both were put on a 1,000-calorie daily diet. The continuous group lost a total of 27 lbs. over the period, and the intermittent group lost slightly more at 28.7 lbs. Few if any side effects were noted. There were no significant differences in systolic and diastolic blood pressure between the groups.
Phentermine Diet Study in Korea:
A more recent trial of phentermine’s weight loss effects was conducted in 2005 in Korea. The dose was raised to the standard 37.5 mg dose. The drug was tested on a total of 34 people,. These subjects were given a 1,500 calories per day diet. After 14 weeks of study, the drug treatment group lost 16.5 lbs. Side effects in this study similar to many more reported are actually much less significant than most people think. Here is the report on side effects from the study:
“… in adverse events analysis, only 6 of 29 (20.7%) phentermine group subjects complaint on their palpitation, and this number is not significantly more than placebo group. Similarly, blood pressure had not increased after treatment period in phentermine group, and there had been no significant difference between both groups. Not only the blood pressure of endpoints but also the blood pressure of 4 weeks administration of phentermine is not significantly different between two groups. Not shown in the results, the analysis of blood pressure at 6th week, i.e. after 4 weeks administration of phentermine, the mean systolic pressure was 127.4 (SD 10.2) mmHg and the mean diastolic pressure was 85.1 (SD 8.4) mmHg in phentermine group (n = 28), compared to systolic 127.3 (SD 12.7) mmHg and diastolic 83.5 (SD 10.4) mmHg in placebo group (n = 24). Therefore, we can suggest that the administration of phentermine would not induce any serious cardiovascular effect at least for the patients whose risk of cardiovascular disease is not high.”
Phentermine Appetite suppressants: Weight Loss Study in US:
Phentermine appetite suppressors were ealuated in male and female patients in the US at UCLA while they participated in a very low calorie diet. Doses ranged from 8 to 30 mg per day and calories were reduced to 500 to 800 calories per day. Exercise was also included in this study. Average weight loss was 17 to 21 lbs after 13 weeks. Average weekly weight loss rate was about 2 lbs per week. Side effects of phentermine are listed below:
Phentermine and the other appetite suppressors remain very effective and play a major role in helping overweight individuals lose weight when used in low doses and titrated slowly over a period of time. Tens of millions of people have taken these medications over the past 45 years without any problems.
Diethylpropion and Tenuate: FDA Approved Diet Pills:
Phentermine appetite suppressants sucesss have been also observed in overweight patients taking Tenuate and diethylproprion. They have a similar adverse-effect and weight loss profile to phentermine, but are much less frequently prescribed, with approximately 1 million prescriptions dispensed between 2008–2011. A meta-analysis of 9 small studies ranging from 6–52 weeks37 found that patients using diethylpropion 75mg/d had a mean additional weight loss relative to placebo of 3.0 kg, with a mean total weight loss of 6.5 kg. I found diethylproprion to be a very useful drug with the least side effects of all weight loss drugs. The fact that it is short activingt (about 5 hours) permits very useful individualization of the drug. For example a full dose can be taken at 10 AM and 5 PM which control appetite over a 12 hour span, especially in the evening when many people need not only appetite suppression but control of cravings. Diethylproprion and Tenuate have very similar chemical structures to Buproprion, marketed as Wellbutrin for many years. Wellbutrin has been shown to diminish compulsive behaviors.
Phendimetrazine, despite the paucity of randomized controlled trials37 is prescribed three times more frequently than diethylpropion for obesity treatment, with more than 3 million phendimetrazine prescriptions estimated to have been filled between 2008–2011.41 In the completer’s analyses from two small 12-week trials,43, 44 it appears to have similar weight loss to other appetite suppressors.
Orlistat (Xenical®, Alli®)
Approved by the U.S. FDA in 1999, Xenical® (orlistat) is not in the appetite suppressants group. It is a lipase inhibitor for obesity management that acts by inhibiting the absorption of dietary fats. Orilstat prevents enzymes in the gastrointestinal tract from breaking down dietary fats into smaller molecules that can be absorbed by the body. This undigested fat is excreted in the bowel movement. Side effects of flatulence, fecal urgency, oily stools and leakage have limited its widespread use.
An over-the-counter version, brand name Alli®, has been on the market for the past two years. While it is expensive and has limited benefits, some studies show that teenagers have done well with it.
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Long Term Weight Loss Medication for Obesity: A Systematic and Clinical Review