Brazil's Anvisa warns against illegal retatrutida weight‑loss pens

Brazil's health regulator Anvisa has issued multiple alerts that retatrutida, an experimental drug under phase‑3 trials by Eli Lilly for obesity and type‑2 diabetes, is being sold illegally on the internet and at the country’s borders. The molecule is not approved in any country, and the company has not filed for registration with any regulatory agency. In the first three months of 2026, customs and Anvisa seized more than R$ 11 million worth of unregistered “weight‑loss pens” containing retatrutida, surpassing the total value seized in all of 2025.

Anvisa warns that products lacking registration provide no guarantee of the active ingredient, correct dosage, or manufacturing quality, exposing users to unknown side‑effects, contamination, and ineffective treatment. The agency urges the public to avoid purchasing or using such products and to report any suspected illegal sales.

A medical education event in Recife also highlighted the growing risk of indiscriminate use of injectable weight‑loss pens, stressing the need for proper medical prescription and scientific evidence before use. Together, these warnings underscore a broader concern over unregulated obesity‑treatment products in Brazil.