Dr. Friedman’s Guide to New And Old Weight Loss Drugs
Dr. Friedman’s initial approach as an Endocrinologist regarding weight loss is to first rule out any endocrine problems, such as hypothyroidism, Cushing’s syndrome, or growth hormone deficiency, that may lead to weight gain. He then encourages the patient to consume a lowcalorie diet, and he often recommends eating an increasing amount of vegetables, as they are low in calories with a large amount of nutrition, as well as to increase exercise. However, many patients need a jumpstart for the weight loss, and this is where weight loss medicine comes into play. There are 2 new weight loss medicines that have been FDA approved in 2012, although it is unclear whether these medicines have an advantage over existing weight loss medicine. Prior to these two FDA approvals, the only weight loss medicine FDA approved for long-term use is Orlistat which is also available over-the-counter as Alli. The prescription version contains 100 mg of Orlistat and is usually given 3 times a day while the over-the-counter form, Alli, contains 50 mg of the drug and the patient can take 1 to 2 pills before each meal. Orlistat works by decreasing fat absorption so in a patient who is consuming a high-fat diet, that fat will not be absorbed and the patient will not get those calories. The patient will also experience diarrhea when eating a high-fat diet, and this may condition the patient not to eat a high-fat diet. However, most of Dr. Friedman’s patients know about eating a low-fat diet and therefore, this drug is not that helpful for most of the patients.
The second drug that has been around for over 50 years is FDA approved for short-term but not for long-term weight loss. This is Phentermine of which the brand name is Adipex. Phentermine was part of the Fen-Phen combination that was quite popular about 20 years ago. Fenfluramine, the drug that is abbreviated Fen, was pulled from the market in 1997 due to valve and lung problems. However, the Phentermine, which is the Phen drug, has remained in use and is actually a quite-effective weight loss medicine. Phentermine works by decreasing appetite and also may have some effects on increased metabolism and is in the family of amphetamine-like drugs. Therefore, the side effects of Phentermine include feeling hyper or jittery, rapid heart beat, increased blood pressure, and trouble sleeping. The drug works quite well short-term in reducing food intake and can often be given before lunch and dinner. The tablets are 37.5 mg in dose and therefore, Dr. Friedman often gives 1/2 tablet before lunch and dinner. In some patients, this keeps them awake at night and therefore, Dr. Friedman may give them a full pill to take in the morning. However, as the drug is only FDA approved for short-term use, Dr. Friedman usually gives this for a period of 2 to 4 months.
One of the 2 new drugs the FDA approved is called Qsymia, which contains Phentermine plus extended-release Topiramate. The Phentermine in the drug is actually a lower dose than in Phentermine itself and is usually given as either 15 mg or 7.5 mg of Phentermine compared to the 37.5 mg which is available as Phentermine alone. Topamax is a drug that was originally developed as a seizure drug that was found to have weight loss properties; however, this drug has a lot of side effects and is actually nicknamed “Stupamax” as it often makes people have decreased memory. Qsymia came out in 2012 and has only recently been used. It is available, but there is some difficulty getting it and it is about $160/month, with only about 1 out of 5 prescriptions covered by insurance. Dr. Friedman does not see any advantage of this drug over Phentermine itself. Therefore, Dr. Friedman has not started using Qsymia in his patients.
The other new drug is called Belviq, of which the generic name is lorcaserin. This is a serotonin 5HT2C receptor agonist that is similar to the fenfluramine that was removed from the market; however, fenfluramine was a 5HT2B receptor agonist and Belviq is a 5HT2C receptor agonist. Therefore, this is likely to be much more safe than the fenfluramine which was removed from the market. However, as of April 2013, this drug is not yet clinically available in the United States due to issues related it being a controlled substance. This drug does seem quite promising, and Dr. Friedman would be interested in prescribing this drug once it becomes available.
In summary, weight loss medicines can be used to help patients lose weight who have already tried diet and exercise and have already had their endocrine problems treated. The drug that is most successful as a weight loss medicine is Phentermine, although the new medicine, Belviq, looks promising.