Health Canada's public advisory on unauthorized and counterfeit GLP-1 receptor agonist products, last updated January 21, 2026, instructs Canadians to verify any prescription product by checking for an eight-digit Drug Identification Number (DIN) on the label and searching Health Canada's Drug Product Database before purchase

A GP, pharmacist, or specialist clinician can: Review your current medication list for potential interactions, particularly with diabetes medications, anticoagulants, thyroid treatments, and hormonal contraceptives Assess your nutritional status and advise on appropriate supplementation only where deficiencies are confirmed Monitor for adverse effects such as hypoglycaemia, gastrointestinal disturbance, or unexpected changes in blood pressure or heart rate Refer you to appropriate NHS services , including Tier 3 weight management programmes, if you are seeking structured support for obesity Discuss contraception and family planning , as retatrutide should not be used during pregnancy or breastfeeding
Leptin The robust regulatory response to rapid BW gain in animals seems similar to the presumably robust regulatory response of ancestral humans but not the weak response of modern humans
The study found no clear differences between GLP-1 drugs and sodium-glucose cotransporter 2 inhibitors (SGLT2i) in terms of lean body mass loss
Without lifestyle changes, weight regain is common after discontinuing GLP-1 receptor agonists