Yes, your doctor can prescribe weight loss medication if you meet certain weight and health criteria. The standard threshold is 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, high cholesterol, sleep apnea, or heart disease. Your primary care doctor can write the prescription, though some people end up working with specialists for more complex cases.
Who Qualifies for a Prescription
The FDA sets the eligibility bar that doctors follow. If your BMI is 30 or above, you qualify regardless of other health conditions. If your BMI falls between 27 and 29.9, you need at least one weight-related comorbidity to be eligible. Common qualifying conditions include type 2 diabetes, high blood pressure, abnormal cholesterol levels, sleep apnea, cardiovascular disease, fatty liver disease, polycystic ovary syndrome, and osteoarthritis.
For reference, a BMI of 30 corresponds to roughly 180 pounds at 5’4″ or 210 pounds at 5’9″. Your doctor will also likely measure your waist circumference, since carrying fat around your midsection (more than 35 inches for women, 40 inches for men) raises health risks even when BMI alone doesn’t tell the full story. Most doctors expect you to have already tried diet and exercise changes before moving to medication, though this isn’t always a strict requirement.
Pregnancy, breastfeeding, or plans to become pregnant rule out all prescription weight loss drugs. Beyond that, each medication has its own list of conditions that make it unsafe, which your doctor will review based on your medical history.
What Medications Are Available
There are five FDA-approved medications for long-term weight management, and they fall into three broad categories based on how they work.
GLP-1 Medications
Semaglutide (Wegovy) and liraglutide (Saxenda) are injectable drugs that mimic a gut hormone called GLP-1. They work on multiple fronts: reducing appetite and hunger, slowing how quickly food leaves your stomach, increasing feelings of fullness after meals, lowering cravings, and even shifting food preferences away from high-calorie options. Wegovy is a once-weekly injection; Saxenda is daily. Both are approved for adults and children 12 and older. You cannot take either one if you or a close family member has had a type of thyroid cancer called medullary thyroid carcinoma.
Combination Pills
Phentermine-topiramate (Qsymia) is a once-daily pill that pairs an appetite suppressant with a seizure medication that also reduces hunger. It’s approved for adults and children 12 and older. It’s off-limits if you have glaucoma or an overactive thyroid, and topiramate raises the risk of birth defects, making reliable contraception essential.
Naltrexone-bupropion (Contrave) combines an addiction-treatment drug with an antidepressant, both of which affect appetite signals in the brain. It’s approved for adults only. You should not take it if you have uncontrolled high blood pressure, a seizure disorder, an eating disorder, or if you use opioids. This medication can also affect mood, and in some cases has been linked to changes in thinking and suicidal thoughts.
Fat Absorption Blocker
Orlistat (Xenical) works in the gut rather than the brain, blocking your body from absorbing about a third of the fat you eat. It’s taken three times daily with meals. It doesn’t suppress appetite, so the experience is quite different from the other options. Unabsorbed fat can cause oily stools, gas, and urgency, especially if you eat high-fat meals.
In terms of results, FDA-approved medications typically produce 5% to 10% total body weight loss, compared to about 3% from behavioral changes alone. GLP-1 drugs, particularly semaglutide, tend to produce results at the higher end of that range.
Which Doctors Can Prescribe Them
Any licensed physician, including your primary care doctor or family doctor, can prescribe weight loss medication. Nurse practitioners and physician assistants can also prescribe in most states. You do not need to see a specialist to get started.
That said, some people benefit from working with doctors who have additional training in obesity medicine or endocrinology. These specialists often work alongside dietitians, exercise physiologists, and psychologists as part of an interdisciplinary team. They tend to have more experience managing dose adjustments, side effects, and the transition off medication. If your primary care doctor isn’t comfortable prescribing these drugs, or if you have complex health conditions, asking for a referral to an obesity medicine specialist is a reasonable next step.
What Happens at the Appointment
Expect your doctor to calculate your BMI, measure your waist, and review your full medical history. Blood work is standard, typically checking your blood sugar, cholesterol, thyroid function, and liver and kidney markers. These tests serve two purposes: confirming whether you have weight-related health conditions that affect eligibility, and making sure it’s safe to prescribe a particular drug given your overall health.
Your doctor will ask about previous weight loss attempts, your eating patterns, physical activity level, and any medications you currently take. Some weight loss drugs interact with antidepressants, seizure medications, and opioids, so a complete medication list matters. If everything checks out, your doctor will recommend a specific medication based on your health profile, preferences (pill versus injection), and which side effects are most acceptable to you.
Most medications start at a low dose and increase gradually over several weeks. This titration period helps your body adjust and minimizes side effects like nausea, which is especially common with GLP-1 drugs early on.
Insurance Coverage Can Be a Hurdle
One of the biggest practical barriers to weight loss medication is paying for it. Many insurance plans either don’t cover anti-obesity drugs or impose strict prior authorization requirements. Private coverage often depends on whether your employer chose to include the benefit, and even when coverage exists, insurers may require documentation that you’ve tried diet and exercise programs first, or that you meet specific clinical criteria beyond the FDA minimums.
GLP-1 medications like Wegovy are particularly expensive without coverage, often running over $1,000 per month at retail price. If your insurance denies coverage, your doctor may consider off-label alternatives. Metformin, commonly used for type 2 diabetes, and topiramate, an anti-seizure drug, both cause weight loss as a side effect and cost far less. These aren’t FDA-approved specifically for weight management, but doctors can legally prescribe them off-label, and some patients see meaningful results. In case reports, patients using these medications lost between 12 and 56 kilograms over periods of three to six months, though results vary widely.
What to Know About Stopping the Medication
Weight loss medications work while you take them. In one study of semaglutide, participants regained two-thirds of the weight they had lost after stopping the drug. This doesn’t mean the medication failed. It means obesity is a chronic condition, and for many people, long-term use is part of the plan, similar to taking blood pressure medication indefinitely.
If you’ve built strong exercise and eating habits while on the medication, you have a better chance of maintaining your results after stopping. But this is worth discussing with your doctor before you start, not after. Ask how long they expect you to stay on the drug, what the plan looks like if you want to stop, and what monitoring you’ll need going forward. Setting expectations early helps you avoid the frustration of regain later.