GLP-1 weight loss medicine starts with your history and your labs

You've tried the diets and the apps. Someone you know started a GLP-1 medicine and looks and feels different, and you want to know whether it could work for you. The fastest path looks like the one with the fewest questions.

It isn't. The questions at the start are what make the rest of it safe and worth doing, and the prescribing labels themselves tell you which ones matter.

Who these medicines are approved for

Semaglutide for weight management is sold as Wegovy, and tirzepatide as Zepbound. Both labels describe the same core use. Zepbound's says it's indicated in combination with a reduced-calorie diet and increased physical activity to reduce excess body weight and maintain that reduction long term in adults with obesity, or adults with overweight who have at least one weight-related condition. Wegovy's label uses the same framing for adults and covers some adolescents as well.

When the FDA approved Zepbound in 2023, it defined those groups as a body mass index of 30 or greater, or 27 or greater with at least one weight-related condition. That's the first thing a provider confirms. The second is the phrase that appears in both labels: in combination with diet and activity. The medicine is designed to work alongside those changes, not instead of them.

Your history matters as much as your labs

Both labels carry a boxed warning and list situations where the medicine shouldn't be used, and some of those depend on your personal and family medical history. Your provider walks through them with you before your first dose.

That's a conversation, not a blood test, and it's one many people have never had. Before your first visit, gather what you know about your own health history and your family's.

What the labels tell prescribers to watch

The warnings sections of both labels list, among others, acute pancreatitis, acute gallbladder disease, hypoglycemia, and acute kidney injury related to dehydration. Those don't happen to most people. They're the reason a provider wants to know your history before you start and to stay in touch once you have.

It's also why your current medicines matter. If you take anything for diabetes, say so at the start, because hypoglycemia is on both labels' list of warnings.

Why a baseline comes first

A baseline is a snapshot of where you start, so later changes can be read against it instead of guessed at. Our weight loss panel covers HbA1c and fasting insulin, a lipid panel, a thyroid panel, liver enzymes and a hormonal screen. The thyroid and hormonal markers matter for another reason: weight that won't move has more than one possible cause, and some of them aren't solved by a GLP-1 at all. If you've struggled with your weight most of your life, your thyroid deserves a full check before you start.

The NIDDK's guidance is plain that you should try to stick with your healthy eating plan and stay physically active while taking weight-loss medicines. That's why our weight loss care pairs the medicine with nutrition guidance, follow-up and re-testing, not a one-time prescription.

4 things to know before your first visit

Your current weight and height. Your personal and family medical history, as best you know it. Whether you've ever had pancreatitis or gallbladder problems. And every medicine you take, especially anything for diabetes.

If you can answer all 4, your first consult can spend its time on you, not on paperwork.

The careful start is the fast one

It's tempting to treat the questions as a hurdle between you and the prescription. They're the opposite. They're what make sure the medicine fits you, and they're what make the follow-up meaningful once you're on it.

Start with your history and your labs. The rest of the plan is built on them.