Semaglutide and tirzepatide are the two most talked-about GLP-1 medications for weight management. They're closely related, but they aren't the same, and the differences matter when you're deciding where to start.

The core difference: one signal or two

Semaglutide is a single-pathway GLP-1 receptor agonist. Tirzepatide is a dual agonist: it activates GLP-1 and a second gut hormone receptor, GIP. In brand head-to-head and SURMOUNT programmes, dual agonism has been associated with larger mean weight-loss averages than single-pathway GLP-1 under trial conditions, not a guarantee of faster personal results.

Results

Both have strong brand clinical track records for weight management. In semaglutide's STEP 1 trial, adults on brand 2.4 mg weekly lost a mean of 14.9% of body weight over 68 weeks versus 2.4% with placebo. In SURMOUNT-1, brand tirzepatide produced dose-dependent mean weight loss of about 15% to 21% over 72 weeks at higher doses. Those trials studied FDA-approved brand products, not the compounded preparations dispensed here. Trial averages are not a promise. Individual results depend on starting weight, habits, dose, and adherence.

At a glance

  • Semaglutide: GLP-1 only · from $166/mo (3-month plan)
  • Tirzepatide: GLP-1 + GIP · from $199/mo (3-month plan)

Price

At DirectGLP, semaglutide starts at $166/month and tirzepatide at $199/month on the 3-month plan. Semaglutide is the more affordable entry point; tirzepatide costs a little more for its dual-receptor action. Both include the provider review, medication, shipping, and support in one transparent price.

Side effects

The side-effect profiles are similar: most commonly mild-to-moderate nausea, digestive changes, and fatigue that tend to ease as your body adjusts during titration. Both carry the same important safety considerations, including contraindications for a personal or family history of medullary thyroid carcinoma (MTC) or MEN 2.

How to choose

There's no universally “better” option, just the one that fits you. A licensed provider weighs your health history, goals, budget, and how you respond, and can adjust or switch your plan over time. That's the point of a provider-led model: the decision is clinical, not a checkout preference.

This article is educational and is not medical advice. GLP-1 medications require a prescription; eligibility is determined by a licensed provider. Compounded medications are prepared by state-licensed 503A pharmacies and are not FDA-approved products. Brand trial results do not transfer automatically to compounded therapy. Individual results may vary.