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Are all weight loss drugs safe?
Last reviewed: 01.07.2025
Non-surgical obesity medications are pharmacological agents that control or reduce weight. They perform a weight-regulating function by altering metabolism, appetite, or calorie absorption.
However, the use of these drugs carries a certain risk to the patient's health and before starting therapy you should be aware of their side effects.
- Phentermine and topiramate
To study the effectiveness of taking combinations of these two drugs, scientists conducted a randomized study. During the experiment, one group of participants took a combination of these drugs, and the second - a placebo. Experts found that the drugs really reduce the patients' weight. Compared to the group that took the placebo, patients who took phentermine and topiramate were able to lose 9% more weight. However, in addition to weight loss, experts found that the drugs have a negative effect on the cardiovascular system, and can also cause birth defects in children. Despite the fact that the patients' weight was going away, the Food and Drug Administration refused to approve these drugs as an effective means of combating excess weight.
- Bupropion and naltrexone
Bupropion is a second-generation antidepressant and has nothing to do with weight loss. In diet pills, it acts as a mood enhancer. This drug is effective in the fight against smoking due to its antidepressant effect, due to which the former smoker does not suffer so much from the symptoms of withdrawal from cigarettes. Like most antidepressants, this drug has side effects: increased excitability or, conversely, drowsiness, dry mouth, abdominal pain, tremors of the limbs.
The second drug causes blockade of opiate receptors, due to which it is successfully used in the treatment of alcohol and drug addicts. Its side effects include nausea, depression, headaches, sleep disturbances, anxiety and much more. In clinical trials, people taking Contrave, which included bupropion and naltrexone, lost an average of only 4.2% more weight than those taking a placebo. These figures were too small for the Food and Drug Administration to approve it. So whether you should take such an explosive mixture is up to you.
- Phentermine, 5-hydroxytryptophan and carbidopa
Phentermine and 5-hydroxytryptophan are used as supplements that suppress appetite and sleep. According to studies, these drugs were prescribed to their patients by about 20% of doctors, despite the fact that their effects have not been fully studied. There is no definitive data on the side effects of these drugs, but it is still known that this combination can cause increased heart rate, increase blood pressure and provoke skin inflammation.
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