Rapid weight loss with no effort — that’s exactly the effect promised in TikTok videos where bloggers show “magic” results after taking Molecule capsules. This supplement is rapidly gaining popularity among young people in Russia and Eastern Europe. However, as a recent BBC investigation revealed, the marketing claims hide a far more dangerous reality. The Conversation reports on the findings.

Although the Molecule packaging lists harmless ingredients — dandelion root, fennel seeds, and black tea — laboratory tests detected sibutramine in the capsules. This medication was once prescribed for weight loss under the brand name Reductil, but was later banned in the U.S., the U.K., and EU countries due to serious side effects.

Sibutramine acts on satiety centers in the brain, increasing levels of serotonin and norepinephrine and reducing appetite. It can raise energy expenditure and help maintain weight after weight loss. Clinical data showed that, as part of a comprehensive approach — diet, exercise, and medical support — people could lose up to 5–10% of their body mass.

But in 2010, the European Medicines Agency and regulators in the U.S. and U.K. banned the drug. A large study, SCOUT, found that sibutramine increases the risk of heart attack and stroke, especially in people with heart disease.

In addition to cardiovascular complications, the drug can cause dry mouth, insomnia, headaches, and can significantly raise blood pressure and heart rate due to activation of the sympathetic nervous system.

Another danger is combining sibutramine with other medications. When taken with antidepressants (such as SSRIs or MAO inhibitors), it can trigger serotonin syndrome — a potentially life-threatening condition. Similar risks exist when it is taken together with certain migraine medications or opioid painkillers.

Symptoms include confusion, agitation, sweating, fever, rapid heartbeat, muscle twitching, and coordination problems. Furthermore, antibiotics and antifungal drugs that affect liver enzymes can increase sibutramine concentrations in the blood.

In Russia, sibutramine is available by prescription for treating obesity in adults. However, it increasingly appears in illegal dietary supplements marketed as “natural” weight-loss remedies — including Molecule capsules. Such products are sold online and bypass quality control, leaving buyers unaware of what they are actually consuming.

Experts stressed that the story of sibutramine is a clear warning about the dangers of unregulated weight-loss pills. Even a medication once approved for widespread use can cause significant harm, especially when sold illegally or taken without medical supervision.