Drug Science

Tirzepatide vs Semaglutide: The Dual-Receptor Difference Explained

By Anthony Fontana, Active tirzepatide patientMedically reviewed by:PendingLast reviewed May 14, 2026Last updated May 14, 2026

Both shots help you lose weight. Both cut blood sugar. They work in two ways that count.

One Target vs Two

Sema hits one target. GLP-1. That gut signal slows the gut and tells the brain you feel full.[1]

Tirz hits two. GLP-1 and GIP. GIP helps the body use fat and sugar. Two hits, more loss.[2]

Side By Side

DrugMakerTargetsMax Weight Loss
SemaglutideNovo NordiskGLP-115 to 17%
TirzepatideEli LillyGLP-1 + GIP20 to 22%

Brand Names

Sema is sold as Ozempic, Wegovy, and Rybelsus. Tirz is sold as Mounjaro and Zepbound. The dose and label vary. The drug is the same.[3]

What I Feel On Tirz

“OMAD without tirzepatide produces confusion and lightheadedness. OMAD with t does not.”

That is what I wrote. One meal a day with no drug felt rough. Same plan with the drug felt fine. Two hits keep blood sugar level.

Dose Steps For Zepbound

Start at 2.5 mg per week. Hold for 4 weeks. Step to 5 mg for 4 weeks. Then 7.5 mg. The FDA label sets the plan. Some folks stop at 5 mg.[4]

Which To Pick

Pick sema for lower cost. Pick tirz if you want more loss or have type 2 that needs more help.

References

  1. FDA Wegovy (semaglutide) prescribing information
  2. FDA Mounjaro (tirzepatide) prescribing information
  3. FDA Zepbound (tirzepatide for weight loss) approval
  4. NIH summary of GIP and GLP-1 receptor agonist class

Compare GLP-1 Telehealth Costs

See which sites offer tirzepatide and what they charge so you can match the right drug to the right path.