Thai FDA Warns Against Improper Use of Weight-Loss Injection Pens, Citing Yo-Yo Effect and Serious Health Risks

The Thai Food and Drug Administration (Thai FDA) has issued a public warning over the improper use of so-called “weight-loss injection pens,” cautioning that misuse can lead to rapid weight regain (the yo-yo effect) and serious adverse health outcomes. The alert follows widespread use and promotion of the injections on social media platforms.

Bangkok, Jan 6, 2026  Suphatra Boonserm, Secretary-General of the Thai FDA, said the agency is deeply concerned after observing increasing use of weight-loss injection pens among the general public, including self-adjustment of doses and injection methods without medical supervision.

She emphasized that in Thailand, medicines in the glucagon-like peptide-1 receptor agonist (GLP-1 RA) group are approved only for the treatment of type 2 diabetes and for weight reduction in patients with obesity not for cosmetic weight loss in otherwise healthy individuals.

GLP-1 RA medications work by promoting early satiety and reducing appetite, which can result in short-term weight loss. However, improper use or discontinuation without medical guidance may cause rapid rebound weight gain, commonly referred to as the yo-yo effect.

The Thai FDA warned that misuse also carries the risk of serious side effects, including hypoglycemia, kidney failure, gallbladder inflammation, depression, and muscle wasting especially among individuals with underlying conditions such as kidney disease, liver disease, thyroid disorders, or other endocrine conditions. These patients require careful evaluation and close medical supervision.

“Despite ongoing enforcement actions against illegal advertising and online sales of these medicines, misuse continues to be a persistent problem,” Suphatra said.

She added that the Thai FDA is currently proposing to the Ministry of Public Health to upgrade the regulatory status of GLP-1 RA medicines from “dangerous drugs” to “special controlled drugs.” If approved, sales would be restricted to licensed pharmacies and require a physician’s prescription, with mandatory sales records to enable effective monitoring.

The Secretary-General also urged the public not to be misled by claims such as “inject and get slim,” stressing that there is no miracle drug for safe and sustainable weight loss. Proper weight management should focus on lifestyle changes, including balanced nutrition, regular exercise, adequate rest, and mental health care approaches that also help reduce long-term risks of non-communicable diseases.

Members of the public who encounter suspicious advertising or illegal sales of health products are encouraged to report them via the Thai FDA hotline 1556, Line @FDAThai, Facebook FDAThai, or local provincial public health offices nationwide.

Source: www.thaihealth.or.th