Tirzepatide, considered.
Tirzepatide hits two incretin receptors instead of one. The result, in head-to-head data, is the largest weight loss ever produced by a non-surgical intervention — at the cost of side effects of similar magnitude to semaglutide.
What dual agonism does differently.
Tirzepatide activates both the GLP-1 receptor (like semaglutide) and the GIP receptor — a second incretin pathway. The combination produces stronger effects on appetite, gastric emptying, and insulin sensitivity than either alone.
In SURMOUNT-1, average weight loss at the 15 mg maximum dose was 22.5% at 72 weeks. For comparison, semaglutide 2.4 mg produces ~15% in similar populations. The efficacy gap is real; the trade-off is similar GI side effects and similar cost.
Who it is for.
FDA labeling (Zepbound) mirrors Wegovy: BMI ≥30, or BMI ≥27 with comorbidity. Tirzepatide is not approved or recommended in pregnancy, type 1 diabetes, or patients with personal/family history of medullary thyroid cancer or MEN2.
Patients who failed to lose meaningful weight on semaglutide often respond to tirzepatide. The reverse is also true. The pharmacology is similar enough that switching is reasonable, different enough that switching sometimes works.
The titration protocol.
Standard: 2.5 mg weekly for 4 weeks, then 5, 7.5, 10, 12.5, 15 mg, advancing every 4 weeks. Many patients reach maximum effect at 10 or 12.5 mg and never need 15. Optimal dose is the lowest dose that produces sustained progress with manageable side effects.
GI side effects (nausea, constipation, reflux) are the rate-limiter for most patients during titration. Most resolve at the maintenance dose. Severe persistent GI symptoms warrant dose reduction, not pushing through.
Common questions.
How does it compare to semaglutide?
Stronger average weight loss (22% vs 15%). Similar side effect profile. Comparable cost. Insurance coverage and individual response usually decide between them.
Compounded tirzepatide — is it real?
The active molecule is real when sourced from licensed compounders. Potency testing varies. As of 2025, FDA shortage status for tirzepatide ended, narrowing the compounding pathway. Branded product is the safer default if affordable.
Will I plateau?
Most patients experience a plateau between months 9 and 18 at maintenance dose. Strategies: dose adjustment, exercise/protein protocol review, reassessment of overall calorie environment. Plateau is biological — not necessarily a sign of failure.
Can I take it with TRT or HRT?
Yes — no clinically significant interactions. Many longevity-oriented protocols combine GLP-1 therapy with hormone optimization. Coordinate prescribers.
What happens when I stop?
Approximately two-thirds of weight is regained within a year. Same biology as semaglutide cessation. Plan for chronic therapy or accept partial regain.