Who is a candidate for GLP-1 weight-loss medication?

Patients often arrive having already done the arithmetic: they know their BMI, they have read that it qualifies, and they want to know which medicine to start. Those are reasonable questions. But candidacy is not only a number. It is a number, plus a history that makes the medicine safe, plus a plan that makes it worth taking. This article walks through all three the way I do in the office.

What the FDA labels actually say

Two medicines currently dominate GLP-1-based weight management: semaglutide, which acts on the GLP-1 receptor, and tirzepatide, which acts on both the GIP and GLP-1 receptors. Each is sold under different brand names for different approved uses — one set of products for type 2 diabetes, another for chronic weight management. That distinction matters, because the labeling (who the product is for, how it is dosed, what the warnings are) belongs to the specific product. Compounded versions have no FDA-approved labeling of their own, so the approved products’ labels are the usual reference for who should and should not take these medicines.⁸

The current weight-management labels describe the eligible population in words rather than numbers: adults with obesity, or adults with overweight in the presence of at least one weight-related comorbid condition, used together with a reduced-calorie diet and increased physical activity.^1,2 The pivotal trials translated those words into body-mass-index thresholds: a BMI of 30 kg/m² or more, or 27 kg/m² or more with at least one weight-related condition.^3,4

The labels also carry indications beyond weight. The semaglutide weight-management product is approved to reduce the risk of major cardiovascular events in adults with established cardiovascular disease and either obesity or overweight, based on the SELECT trial,⁵ and the injection is also labeled for adolescents 12 and older with obesity. The tirzepatide weight-management product is also approved for moderate-to-severe obstructive sleep apnea in adults with obesity. This article focuses on adults seeking weight management.

Two points are easy to miss. First, “adjunct to diet and physical activity” is part of the approved use, not decoration. Second, the labels advise against combining these products with any other GLP-1 receptor agonist, including a diabetes product containing the same molecule.^1,2

Which weight-related conditions count

For a BMI between 27 and 30, the question is whether weight is already affecting your health. In the trials, qualifying conditions included high blood pressure, abnormal cholesterol, obstructive sleep apnea and cardiovascular disease; type 2 diabetes and prediabetes are also weight-related conditions that physicians commonly consider.^3,4 In practice I also ask about fatty liver disease, joint pain that limits activity, and anything else in your history where weight is part of the picture.

BMI is a crude measure. It does not distinguish muscle from fat, and it can under- or over-estimate risk in different bodies. It is still the measure the labels and trials use, so it is where eligibility is documented — but waist circumference, blood pressure, labs and how you actually function all shape the recommendation.

Who should not take these medicines

The labels list a small number of absolute contraindications. You should not start a semaglutide- or tirzepatide-based weight-management product if you have:^1,2

• A personal or family history of medullary thyroid carcinoma (MTC), or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Both products carry a boxed warning because they caused thyroid C-cell tumors in rodents; whether they do so in humans is unknown.
• A prior serious hypersensitivity reaction to the medicine or any of its ingredients.

Pregnancy is the other firm line. The labels advise that weight loss is not recommended during pregnancy and that the medicine be stopped when pregnancy is recognized; because semaglutide stays in the body for a long time, its label advises stopping at least two months before a planned pregnancy.^1,2 If you are trying to conceive, that changes the plan.

Conditions that call for extra caution

Beyond the contraindications, the labels’ warnings describe situations where a physician needs to weigh risks carefully, adjust other medicines, or decide that now is not the right time:^1,2

• Pancreatitis. Acute pancreatitis has been reported. A past episode does not automatically exclude you, but it is a serious consideration and is discussed individually.
• Gallbladder disease. Gallstones and gallbladder inflammation occurred more often with the medication than with placebo; rapid weight loss itself raises the risk.
• Severe gastrointestinal disease. These medicines slow stomach emptying and are not recommended for people with severe gastroparesis.
• Kidney disease. Vomiting and diarrhea can cause dehydration and acute kidney injury, particularly while the dose is being increased.
• Diabetes treated with insulin or a sulfonylurea. The combination raises the risk of low blood sugar; those doses often need to come down.
• Diabetic retinopathy. People with diabetes and retinopathy need monitoring, because rapid improvement in blood sugar has been associated with temporary worsening.
• Upcoming surgery or sedation. Delayed stomach emptying raises the risk of aspiration under anesthesia, so your surgical team needs to know.
• Oral contraceptives. The tirzepatide label advises switching to a non-oral method, or adding a barrier method, for four weeks after starting and after each dose increase.

Some cautions come from clinical judgment rather than the label. A history of an eating disorder, for example, changes how I think about an appetite-suppressing medicine, and I will say so directly.

The history and labs we review

PrimeCell’s GLP-1 program uses compounded GLP-1 medications, prescribed only after a physician evaluation. Compounded drugs are not FDA-approved, and the FDA does not review them for safety, effectiveness or quality. They are not the same as, and should not be assumed equivalent to, Wegovy or Zepbound.

At PrimeCell, the GLP-1 program starts with a history that is longer than most people expect: your weight trajectory over the years, what you have tried and what happened when you stopped, sleep, stress, alcohol, current medicines (some cause weight gain), prior surgeries, and the personal and family history that the contraindications above depend on — including thyroid cancer in relatives, which people often do not think to mention.

Labs are reviewed or ordered based on that history. They commonly include blood sugar and hemoglobin A1c, kidney function and electrolytes, liver tests, a lipid panel and thyroid testing, with others added when your history points to them. Recent results from your primary care physician are welcome and often enough. The purpose is practical: to find a reason not to prescribe, to set a baseline for monitoring, and to catch conditions — prediabetes, fatty liver, an untreated thyroid problem — that change the plan.

What happens at the evaluation

The first visit is an evaluation, in office or, for eligible Florida patients, by telemedicine. It ends with one of three answers:

1. Yes, reasonably. You meet the labeled criteria, nothing in your history argues against it, and you understand the commitment. The medication is a compounded GLP-1 medication, and we explain what that means before you start; then we choose a starting dose and plan the first weeks — including side effects and what to eat when appetite drops. The options, including FDA-approved brand-name products you may be able to obtain through your own insurance or pharmacy, are part of that conversation.
2. Not yet. Something needs attention first: a lab result, a medication that should be changed, surgery on the calendar, a pregnancy plan.
3. No — and here is what else can help. A contraindication, or a situation where the risks outweigh the likely benefit. That answer comes with alternatives, not a closed door.

In each case you should leave understanding why. Program fees are explained at the consultation, and what to expect at your first visit covers the practical details.

Candidacy includes expectations

The last part of candidacy is the least measurable. These medicines work best for people who will come back for follow-up, report side effects rather than push through them, eat enough protein when appetite is low, and do some form of strength training. They also require an honest conversation about the long term: in trials where the FDA-approved medicine was stopped, most participants regained a substantial share of the weight within a year.⁶ Those trials studied the approved products, and their results cannot be assumed to apply to compounded versions.⁷ That is not a reason to avoid the medication. It is a reason to start with a maintenance plan already in mind.

My own view is shaped by personal experience as well as clinical training: I lost roughly 100 pounds over one year during a weight-loss journey that included GLP-1 therapy. That is my story, not a prediction for anyone else. It is the reason I take the unglamorous parts of candidacy — the history, the labs, the follow-up — as seriously as the prescription.