Semaglutide vs Tirzepatide: Which GLP-1 Is Better for Weight Loss?

If you're researching medical weight loss, two names dominate the conversation: semaglutide (the active ingredient in Ozempic and Wegovy) and tirzepatide (Mounjaro and Zepbound). Both are injectable medications that quiet appetite, slow digestion, and help patients lose meaningful weight — but they are not the same drug, and they don't produce the same results. At Go Figure Health in Westminster, Colorado, we prescribe both and tailor the choice to each patient. Here's an honest, side-by-side comparison to help you understand what sets them apart.

Semaglutide vs Tirzepatide at a Glance

- Mechanism: semaglutide targets one hormone pathway (GLP-1); tirzepatide targets two (GIP + GLP-1)

- Average weight loss in trials: ~15% of body weight (semaglutide 2.4 mg, 68 weeks) vs ~20.9% (tirzepatide 15 mg, 72 weeks)

- Brand names: Ozempic and Wegovy (semaglutide) vs Mounjaro and Zepbound (tirzepatide)

- Dosing: both are once-weekly injections titrated upward roughly every 4 weeks

- Side effects: similar GI profile; tirzepatide is often described as slightly better tolerated

- Cost: brand-name pricing is comparable ($1,000–$1,400+/month cash); compounded options cost far less

- Best for: semaglutide for a 10–15% goal or a gentler start; tirzepatide for a larger goal, insulin resistance, or a semaglutide plateau

Quick Answer: How Are They Different?

Semaglutide is a GLP-1 receptor agonist — it mimics one gut hormone (GLP-1) that signals fullness and slows gastric emptying. Tirzepatide is a dual GIP and GLP-1 receptor agonist — it activates *two* gut hormone pathways. That second pathway (GIP) is part of why tirzepatide tends to produce more weight loss in head-to-head trials, but it also means a different side-effect and tolerance profile.

Effectiveness: What the Clinical Data Shows

In the STEP trials, patients on semaglutide 2.4 mg lost an average of about 15% of body weight over 68 weeks alongside lifestyle changes. In the SURMOUNT-1 trial, patients on tirzepatide 15 mg lost an average of 20.9% of body weight over 72 weeks. The 2023 SURMOUNT-5 head-to-head trial directly compared the two and found tirzepatide produced roughly 47% more weight loss than semaglutide at maximum tolerated doses.

That said, *average* results hide a lot of variation. Plenty of patients lose 15–18% on semaglutide and do beautifully. The right medication is the one your body tolerates, you can stay on consistently, and that fits your budget and goals.

Side Effects: What to Expect From Each

Both medications share a similar side-effect profile because they act on overlapping gut pathways. The most common side effects are:

- Nausea (especially in the first 4–8 weeks and after dose increases)

- Constipation or diarrhea

- Reflux or burping

- Fatigue during dose escalation

- Reduced appetite (this is the intended effect, but it can go too far)

In practice, tirzepatide is often described as slightly *better tolerated* by patients, possibly because GIP activity blunts some GLP-1-driven nausea. But that's individual — some patients feel better on semaglutide. Serious side effects like pancreatitis and gallbladder issues are rare but possible with both. Neither medication is appropriate for patients with a personal or family history of medullary thyroid carcinoma or MEN 2 syndrome.

Dosing and Administration

Both are once-weekly subcutaneous injections given with a small pen-style needle in the abdomen, thigh, or upper arm. Both are escalated slowly to limit side effects:

Semaglutide titration (typical): 0.25 mg → 0.5 mg → 1.0 mg → 1.7 mg → 2.4 mg, increasing roughly every 4 weeks as tolerated.

Tirzepatide titration (typical): 2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg, also every 4 weeks as tolerated.

Slower titration is often more comfortable than the package-insert schedule, and we adjust the pace to match how each patient is feeling. Rushing a dose increase is the most common cause of unnecessary nausea.

Cost and Access

Brand-name semaglutide (Wegovy, Ozempic) and tirzepatide (Zepbound, Mounjaro) can run $1,000–$1,400+ per month without insurance. Insurance coverage for weight loss is inconsistent — many plans cover them for type 2 diabetes but not for obesity.

Many clinics, including Go Figure Health, also offer compounded semaglutide and compounded tirzepatide through licensed pharmacies, which is typically a fraction of the brand-name cash price. Compounded medications are not FDA-approved products — they are prepared by state-licensed compounding pharmacies under specific FDA regulations. We walk every patient through what that means before they start.

Which One Is Right for You?

Semaglutide may be a better fit if you:

- Have a lower starting BMI or a more modest weight loss goal (10–15%)

- Have responded well to GLP-1-only medications in the past

- Prefer to start with the longest-studied option in this class

- Are sensitive to medication and want a gentler-feeling option to start

Tirzepatide may be a better fit if you:

- Have a higher starting BMI or a more aggressive weight loss goal (15–25%)

- Have plateaued on semaglutide at a maximum tolerated dose

- Tolerate medications well and want the strongest available appetite effect

- Have type 2 diabetes or insulin resistance (the GIP component helps glucose control)

Neither medication works in isolation. The patients who keep their weight off are the ones who use the medication as a tool *alongside* protein-forward eating, strength training, sleep, and accountability. That's the foundation of our weight management coaching program, and it's why we don't prescribe GLP-1s without it.

How We Decide at Go Figure Health

Every new patient meets with our team for a full intake — medical history, current medications, lab review when needed, goal-setting, and a body composition scan. Based on that, we'll recommend semaglutide, tirzepatide, or a non-GLP-1 path entirely. If you start on one and it isn't the right fit, we switch. No long contracts, no pressure.

Important Note

This article is educational and not a substitute for medical advice. GLP-1 medications require a prescription and medical supervision. Side effects, eligibility, and results vary. Compounded semaglutide and tirzepatide are not FDA-approved medications. Talk with a licensed clinician before starting or stopping any prescription.

Ready to Talk to a Real Clinician?

If you're trying to decide between semaglutide and tirzepatide — or whether a GLP-1 is right for you at all — we'll help you sort through it without the marketing spin. Schedule a consultation or call (720) 513-0001.