There are mixed reviews about the recent approval of lorcaserin (Belviq) and its new availability as a prescription weight loss drug. Obesity has become an epidemic in the United States and across the world and the maker of lorcaserin, Arena Pharmaceuticals, will market this drug as a supplement to drug and exercise to help patients reach their weight loss goals faster. Every drug has side effects and I felt it was important to look closer at some of the possible reactions.
Lorcaserin activates the serotonin 2C receptor which helps you eat less and feel full sooner. Previous weight loss drugs activated the 2B receptor and caused damage to heart valves. Cardiovascular health will be monitored once this hits the market to ensure no damage to the heart valves occur, as there were concerns about this in trials. In October 2010, lorcaserin was rejected by the FDA due to a cancer signal being detected. It caused mammary tumors in rats, which the makers believe is related to the animal themselves and should not have the same effect in human subjects (although prolactin levels can become increased in humans leading to breast development in men and lactation in women).
Multiple studies had patients with and without diabetes treated long term for one to two years with nearly 8,000 patients participating. Those who were randomized with lorcaserin along with diet and exercise counseling lost 3 to to 3.7 percent more weight. The drug should be discontinued if the patient does not lose at least five percent of their body weight in the first twelve weeks.
Now, because this medication has an effect on serotonin I would put a HUGE warning on this when used with antidepressants (Paxil, Lexapro, Zoloft, Cymbalta, Effexor) and pain medications like tramadol. Serotonin syndrome can result in seizures.
Belviq also could possibly effect memory and affection attention levels. For someone like me who needs to stay sharp and focused I don’t want something to make me feel fuzzy.
Upon stopping the medication many patients may experience withdrawal-like side effects like feeling jittery, headaches and insomnia. There is no recommendation at this point of decreasing the dose slowly to avoid these effects but it might be a reasonable thing to consider and ask your doctor about.
The most common side effects of Belviq in non-diabetic patients are headache, dizziness, fatigue, nausea, dry mouth, and constipation; in diabetic patients there is low blood sugar (hypoglycemia), headache, back pain, cough, and fatigue. Belviq should also be avoided during pregnancy and is not recommended for children under 18 at this time.
The good news is that the drug company has to conduct six long-term post-market studies, which means they will be looking at the drug’s effects after it’s on the market. Many drugs, like Vioxx and Bextra, are pulled off the market when damaging information surfaces because of post-market studies like this. Though I’d like to believe that the side effects will make people more hesitant to try Belviq, I know better. Without more guidance in the nutrition and exercise departments, people will continue to look for a miracle solution.
image via FDA
July 9th, 2012