The prescription weight loss landscape changed significantly when GLP-1 medications arrived. For the first time, drugs were producing weight loss results that previously only surgery could achieve. But prescription weight loss isn't one thing; it's a category with very different medications, very different side effect profiles, and very different costs.
Not all prescription weight loss medications work the same way.
GLP-1 receptor agonists (semaglutide, tirzepatide — branded as Ozempic, Wegovy, Mounjaro, Zepbound) mimic a hormone your gut naturally releases after eating. They slow stomach emptying, reduce appetite signals in the brain, and help regulate blood sugar. These aren't stimulants. Most people experience a significant reduction in food "noise" — the constant preoccupation with food that many people with obesity describe. Clinical trials showed 15% to 22% average body weight loss over 68 weeks, which is substantially higher than any previous drug class.
Older appetite suppressants like phentermine work differently — they're stimulants that reduce appetite by activating the sympathetic nervous system. They're effective short-term but are generally approved for only 12 weeks due to cardiovascular effects and dependency concerns.
Orlistat blocks fat absorption in the gut. It's available in both prescription strength and lower-dose over-the-counter form. It's less effective than GLP-1s and has notable gastrointestinal side effects when you eat high-fat meals.
Combination medications like phentermine-topiramate (Qsymia) and naltrexone-bupropion (Contrave) work through multiple mechanisms and show moderate effectiveness.
Doctors generally prescribe weight loss medications to patients with a BMI of 30 or higher, or a BMI of 27 or higher with at least one weight-related health condition such as type 2 diabetes, high blood pressure, or sleep apnea.
GLP-1 medications are not recommended for people with a personal or family history of medullary thyroid carcinoma or MEN2 syndrome. They're not approved during pregnancy. People with a history of pancreatitis should discuss risks carefully.
A real prescription requires a real evaluation — a telehealth visit or in-person appointment where a provider reviews your health history, current medications, and whether any of these drugs are appropriate for you.
GLP-1 medications: Most people start at a low dose and increase slowly over several months. The slow titration exists to manage side effects — primarily nausea, which is common early on and usually improves. Other side effects include vomiting, constipation, and in some people, muscle mass loss if not eating enough protein. The medication requires weekly injections for most formulations. Results build gradually — significant weight loss typically shows clearly after 3 to 6 months.
What happens if you stop: Weight often returns when GLP-1 medications are discontinued. These medications are increasingly viewed as long-term treatments rather than short-term interventions, similar to blood pressure medications.
List prices for GLP-1 medications run $900 to $1,400 per month. Insurance coverage is inconsistent — many plans cover them for type 2 diabetes (Ozempic, Mounjaro) but not specifically for weight loss (Wegovy, Zepbound). Coverage is changing, but slowly.
Compounded semaglutide became widely available when the brand-name drugs were on the FDA shortage list, at significantly lower prices. The FDA shortage designation has changed — search for current status before assuming compounded versions are available or FDA-approved, as this situation has shifted multiple times.
Manufacturer savings programs exist for commercially insured patients and can reduce monthly costs significantly. Eligibility and availability change.
Search current insurance coverage policies for your specific plan. Search whether your state has any particular prescribing requirements. Search current availability of manufacturer discount programs. And search for patient reviews of the specific telehealth or in-person provider you're considering — the experience of starting these medications varies significantly based on the quality of follow-up care and dosing guidance you receive.