Starting semaglutide for weight loss involves getting a prescription, meeting specific health criteria, and gradually increasing your dose over several months. The process is designed to be slow and methodical, giving your body time to adjust to the medication and minimizing side effects. Here’s what each step actually looks like.
Who Qualifies for a Prescription
Semaglutide for weight loss (sold as Wegovy) is FDA-approved for adults with a BMI of 30 or higher, which qualifies as obesity. If your BMI falls between 27 and 29.9, you can still qualify if you have at least one weight-related health condition, such as high blood pressure or high cholesterol. It’s also approved for adolescents aged 12 and older with obesity.
There are a few groups who cannot take semaglutide. If you or a close family member has a history of medullary thyroid cancer, or if you have a condition called Multiple Endocrine Neoplasia syndrome type 2, the medication is off the table. The same applies if you’ve ever had a serious allergic reaction to semaglutide.
What Happens at Your First Appointment
Your doctor will likely order blood work before writing a prescription. This typically includes a comprehensive metabolic panel, which checks your blood sugar, electrolyte balance, and kidney and liver function. You’ll also get a lipid profile to measure cholesterol and triglycerides, along with a hemoglobin A1c test that shows your average blood sugar over the past few months. Kidney function tests are common too. These results give your provider a baseline to track how your body responds to the medication over time.
Beyond lab work, expect a conversation about your weight history, any previous attempts at losing weight, and your current diet and activity level. Most insurers and prescribers want to see that you’re combining the medication with a reduced-calorie diet and increased physical activity. This isn’t just a formality. Semaglutide works best alongside lifestyle changes, and insurance companies often require documentation of both for coverage approval.
The Dose Escalation Schedule
You won’t start at the full dose. The FDA-approved starting dose is 0.25 mg injected once per week, and it stays there for four weeks. This initial dose isn’t really meant to produce significant weight loss. It’s about letting your digestive system adjust to the drug.
From there, your provider will increase the dose roughly every four weeks. The target maintenance dose for weight loss with Wegovy is 2.4 mg per week. Getting there takes about 16 to 20 weeks, depending on how well you tolerate each increase. Some people experience stronger side effects at certain dose jumps, and your doctor may hold you at a lower dose for an extra few weeks before moving up. The goal is to find a dose that’s effective while keeping side effects manageable.
How to Give Yourself the Injection
Semaglutide comes in a prefilled pen with a small needle. You inject it just under the skin, not into muscle. The three recommended sites are your stomach (about two inches away from your belly button), the front of your thigh (avoiding the inner thigh), and the back of your upper arm between the shoulder and elbow. The stomach tends to be the most popular choice because it has a large surface area and the fat layer there allows for good absorption.
Rotate your injection site each week. If you inject in your stomach this week, try your thigh next week and your upper arm the week after. This prevents skin irritation, discomfort, or changes in the tissue at any one spot. You can inject on any day of the week, but try to keep it consistent. If you do need to change your injection day, just make sure at least 48 hours have passed since your last dose.
Storing Your Pen Correctly
Before you use a pen for the first time, it needs to stay in the refrigerator between 36°F and 46°F. Once you’ve used it, you have two options: keep it in the fridge or store it at room temperature between 59°F and 86°F. Either way, an opened pen is good for up to 56 days. After that, discard it and start a new one, even if medication remains inside. Never freeze the pen, and keep the cap on when it’s not in use to protect it from light.
Managing Nausea and Other Side Effects
Nausea is the most common side effect, especially during the first few weeks and after each dose increase. It tends to improve as your body adjusts, but there’s a lot you can do to make it more tolerable.
Start by cutting your usual portion sizes in half. Eat slowly, finish what’s on your plate, then wait 15 to 20 minutes before deciding if you want more. Semaglutide slows how quickly food leaves your stomach, so the volume you used to handle comfortably may now feel like too much. Eating protein first at each meal is a smart strategy because the medication can significantly reduce your appetite, and you want to make sure you’re getting enough nutrition from what you do eat.
When nausea hits, stick to bland, low-fat foods: crackers, toast, rice, soup, and gelatin. Avoid fried foods, spicy dishes, fatty cuts of meat, and anything highly acidic, all of which can worsen both nausea and heartburn. Sugary drinks like soda, juice, and energy drinks should be off the list too. Focus instead on lean proteins, non-starchy vegetables, whole grains, berries, lentils, and beans. Prebiotic fibers and resistant starches (found in foods like lentils and slightly underripe bananas) support digestive health and complement what the medication is doing.
Insurance Coverage Can Be Complicated
Getting insurance to cover semaglutide for weight loss is one of the biggest hurdles. Many plans explicitly exclude medications prescribed solely for weight loss. UnitedHealthcare, for example, covers Wegovy for cardiovascular risk reduction or a specific liver condition, but not for weight management alone. Other major insurers have similar restrictions.
If your plan does offer coverage, expect a prior authorization process. Your doctor will need to submit documentation showing your BMI, any weight-related health conditions, and that you’re following a reduced-calorie diet with increased physical activity. Some insurers require evidence that you’ve tried other weight loss interventions first. This process can take days to weeks, so factor that into your timeline. If coverage is denied, your provider’s office can often file an appeal. Manufacturer savings programs and telehealth weight loss clinics are alternatives some people explore when insurance falls through, though out-of-pocket costs can run over $1,000 per month without coverage.
What the First Month Looks Like
During the first four weeks at 0.25 mg, you may notice a modest decrease in appetite and some mild nausea. Dramatic weight loss isn’t typical yet. This phase is about building the habit of your weekly injection, figuring out which injection site you prefer, learning what foods sit well with you, and establishing the dietary patterns that will matter more as the dose goes up. Working with a registered dietitian during this period can help you build a sustainable eating plan rather than simply eating less by default.
By the time you reach the maintenance dose several months later, most people have found their rhythm with the medication. Side effects have typically leveled off, portion sizes feel natural rather than forced, and the weight loss trajectory becomes clearer. The medication is designed for long-term use, so the habits you build in these early weeks set the foundation for what comes next.