Reports of poisoning tied to injectable weight-loss drugs in the Netherlands doubled to 149 in 2025 from 76 a year earlier, according to the National Poisons Information Center (NVIC). The center also reported its first cases involving unregistered slimming medications and experimental peptide-based substances.

Poisoning occurs when the body is exposed to too much of an active substance or when harmful or illegal compounds are present, the NVIC, part of UMC Utrecht, found. Symptoms can include nausea, vomiting, dizziness, a rapid heart rate, and high blood pressure. In severe cases, patients may develop dehydration, liver damage, or kidney failure.

The NVIC said 40 percent of reports involving medications containing semaglutide, liraglutide, and tirzepatide involved use without a doctor’s supervision.

The center also recorded six reports involving retatrutide, an experimental weight-loss drug. In the first five months of 2026, that number rose to 12. The drug is not registered in the Netherlands and cannot be prescribed by physicians.

Intensive care toxicologist and NVIC head Dylan de Lange warned about increasing informal use of injectable products. He told NOS, “More and more people are sometimes using all kinds of vague products daily, with all the associated risks.”

He added that users often do not know what they are injecting. He said, “In many cases, people themselves do not even know what they are injecting.”

De Lange said social media is contributing to the trend. He described it as dangerous. He said, “The list of possible acute and chronic health risks of online-ordered substances is endless.”