A class of drugs developed for type 2 diabetes turned out to produce substantial weight loss, and their adoption for that purpose has been among the fastest in pharmaceutical history.
What they do
Mimic a hormone that regulates appetite and slows digestion. People taking them feel full sooner and think about food less. The weight loss in trials is larger than any previous medication achieved and approaches what surgery produces.
What is established
The weight loss is real and sustained while the drug is taken. Cardiovascular benefits have been shown in trials, independent of the weight effect. Side effects are common and mostly gastrointestinal.
Stopping the drug leads to weight regain in most people, which means it is a long-term treatment rather than a course.
What is not settled
Long-term safety beyond the trial periods, which are years rather than decades. The right patient population, since demand vastly exceeds the group for whom the evidence is strongest. And whether the muscle loss that accompanies the weight loss matters for health.
The wider effects
Food companies have reported changes in purchasing patterns. Bariatric surgery demand has shifted. Health insurers are wrestling with the cost of covering a permanent medication for a large population.
And supply, which lagged demand for years, produced shortages that affected the diabetic patients the drugs were designed for.
What this is not
Medical advice. Whether these drugs are appropriate for any individual is a question for a doctor who knows their history. This is a description of what changed, not a recommendation.