GLP-1 medications, explained.

A quick vocabulary note, because the brand names cause real confusion. Semaglutide is one molecule sold as Ozempic for type 2 diabetes and as Wegovy for weight management. Tirzepatide is another molecule sold as Mounjaro for diabetes and as Zepbound for weight. Same active drug, different label and dose depending on what it's approved to treat. When people say "GLP-1s," they usually mean this whole family, even though tirzepatide is technically a step beyond it.

These medicines are genuinely effective, and they are genuinely medicine: a mechanism, a dosing schedule, real side effects, and rules about who should and shouldn't take them. None of that fits on a billboard, so here it is in full. This guide is education, not a prescription and not medical advice.

How they actually work.

GLP-1 (glucagon-like peptide-1) is a hormone your own gut releases after you eat. The medicines are engineered copies of it that last far longer in the body: a once-weekly injection instead of a signal that fades in minutes. What that copy does breaks down into a few plain jobs.^[1]

• It turns down appetite. GLP-1 talks to the appetite centers of the brain. In practice, people feel full sooner, stay full longer, and think about food less. The mental "food noise" quiets down. Eating less stops feeling like a constant act of willpower, which is the whole point.
• It slows gastric emptying. The medicine slows how fast your stomach hands food off to the intestine. Meals sit longer, so fullness lasts and hunger takes longer to come back. This is also the source of most of the early nausea, because the stomach is quite literally doing things more slowly.
• It sharpens the insulin response. When blood sugar is high, GLP-1 prompts the pancreas to release insulin and dials back glucagon, the hormone that pushes sugar up. The result is steadier blood sugar and fewer of the crashes that drive snacking. This is why the class started life as a diabetes treatment before its effect on weight became the headline.^[1]

Tirzepatide adds a second lever. Alongside GLP-1, it also mimics GIP (glucose-dependent insulinotropic polypeptide), another gut hormone involved in how the body handles food and energy. Hitting two receptors instead of one appears to add to the appetite and metabolic effect, which is one reason tirzepatide's trial numbers ran higher than semaglutide's. That's why you'll see it called a "GLP-1/GIP" medicine rather than a plain GLP-1.

What the trials actually showed.

Two large, well-run trials anchor most of what we know, and it's worth quoting them honestly rather than rounding up.

Semaglutide, the STEP 1 trial. Adults with overweight or obesity, without diabetes, took semaglutide 2.4 mg weekly alongside diet-and-activity counseling for 68 weeks. Average weight loss was about 15% of body weight (14.9%, to be exact), compared with roughly 2% on placebo.^[2]

Tirzepatide, the SURMOUNT-1 trial. A similar population took tirzepatide weekly for 72 weeks. At the highest 15 mg dose, average weight loss reached about 21% of body weight. Lower doses landed lower.^[3]

Now the fine print that matters more than the numbers:

• These are averages over more than a year. Sixty-eight to seventy-two weeks is a long, supervised program with the dose raised gradually. Not a month, and not a "before-and-after" you'll see by summer. The first stretch is about tolerating and titrating the medicine, not dramatic figures.
• Individual results vary, a lot. An average of 15% or 21% means some people lost considerably more and some considerably less, and a minority didn't respond much at all or couldn't tolerate the drug. An average is not a promise, and any site quoting one number as your number is selling, not informing.
• The medicine came with lifestyle support, not instead of it. Trial participants also got nutrition and activity counseling. The drug does the heavy lifting on appetite; the foundation still matters for keeping muscle and holding the result.

Side effects, and why the dose climbs slowly.

The common side effects are gastrointestinal and they follow directly from the mechanism: nausea, vomiting, diarrhea, and constipation. They're usually worst early on and in the days after each dose increase, and for most people they ease as the body adapts. Some people never get them. Some get them badly enough to stop.

This is exactly why these medicines are titrated, meaning started at a low dose and stepped up over months rather than begun at a full dose. The slow climb gives your gut time to adjust and is the single biggest lever for staying comfortable. Rushing the dose is how people end up miserable and quit a medicine that might have worked. Titration is a feature, not a delay, and a program that pushes you up the ladder faster than you can tolerate is doing it wrong.

Practical measures help the everyday version: smaller meals, eating more slowly, easing off very fatty or very large meals, and staying well hydrated, especially since heavy vomiting or diarrhea can dehydrate you and strain the kidneys. Beyond the common effects there are less frequent but serious risks, including pancreatitis and gallbladder problems, which is what the safety box below is for. If severe or persistent abdominal pain shows up, that's a call-your-doctor situation, not a push-through-it one.

Branded vs. compounded, told straight.

You'll run into two very different ways of getting these medicines, and the difference is worth understanding before you fill anything.

Branded means the FDA-approved product made by the manufacturer: Wegovy or Zepbound for weight, Ozempic or Mounjaro for diabetes. It's the version studied in the trials above, with consistent, regulated manufacturing.

Compounded means a pharmacy prepares a version of the drug itself. Compounding is a legitimate, long-standing part of pharmacy, and it became widespread for these medicines during periods when branded supply couldn't meet demand. But a compounded product is not FDA-approved, and quality, sourcing, and dosing consistency genuinely vary from one pharmacy to the next. Some sourcing is careful and reputable; some is not, and the marketing rarely tells you which you're looking at.

What happens when you stop.

This is the part the ads skip, so here it is plainly: these medicines treat a chronic condition, and stopping tends to reverse the benefit. That isn't a rebound punishment or a sign you did something wrong. It's biology. The appetite signals the drug was quieting come back when the drug leaves, and weight tends to follow.

The evidence is consistent across trials:

• In the extension of the STEP 1 trial, participants who came off semaglutide regained about two-thirds of their lost weight within a year, with the cardiometabolic improvements drifting back toward baseline too.^[4]
• In STEP 4, people who kept taking semaglutide continued to lose weight over the following months, while those switched to placebo regained.^[5]
• SURMOUNT-4 told the same story for tirzepatide: continuing the medicine maintained and even added to the loss, while stopping led to substantial regain.^[6]

The honest takeaway isn't "you're stuck injecting forever." It's that stopping should be a plan, not an event. Depending on the person, that might mean settling onto a lower maintenance dose, tapering off with a real lifestyle scaffold in place, or continuing long-term the way many people continue blood-pressure or thyroid medication, because the underlying condition is chronic and not because the drug is addictive. A doctor who's still paying attention months in is the difference between a thoughtful transition and a discouraging bounce-back.

Who these medicines aren't for.

Good medicine is as much about who shouldn't take a drug as who should. These are the lines a responsible prescriber won't cross without a serious conversation, and some that won't be crossed at all:

• A personal or family history of medullary thyroid carcinoma (MTC), or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). These are contraindications, tied to the boxed warning below.
• Pregnancy, trying to conceive, or breastfeeding. GLP-1 medicines aren't used in any of these situations.
• A history of pancreatitis, gallbladder disease, or severe digestive disorders, which call for a careful case-by-case discussion before anything is prescribed.
• Type 2 diabetes managed with insulin or sulfonylureas, where these medicines can cause low blood sugar and doses may need adjusting. People with diabetic eye disease also need monitoring.
• An active eating disorder, which deserves dedicated specialist care rather than an appetite-suppressing medicine.
• Anyone under 18. everydaymd serves adults; pediatric use exists but belongs with a specialist, not here.

These medicines deserve to be approached as what they are: powerful, useful, and worth doing carefully. That means a real evaluation before anything is prescribed, baseline labs where your history calls for them, and a plan built around slow titration and genuine follow-up rather than a one-time script and silence. It also means the conversation about what you'd actually be taking happens up front. Your doctor tells you exactly what would be prescribed, whether branded or compounded, which molecule and which dose, and the pharmacy that fills it tells you what it charges, before a single thing is filled.

If a GLP-1 isn't right for you, we'll say so and explain why. And if it is, your doctor will start low, go slow, and stay with you through the months where good care actually earns its keep, including the eventual question of maintenance or coming off. You can read how the care works on our weight-loss page, see plain pricing for visits and membership on our pricing page, and review our telehealth consent before any visit.

One last thing worth saying plainly. This guide is education, not a prescription and not medical advice. Your own plan comes from a visit with a physician who knows your history. everydaymd does not prescribe, dispense, or sell medication and takes no payment for it. Your visit fee pays for a physician's time, and anything a clinician prescribes is dispensed and billed by an independent licensed pharmacy.