Switching GLP-1 Medications: When to Change and How to Do It

Switching GLP-1 medications—whether from one drug to another, one provider to another, or brand to compounded—is more common than you'd think. The market is competitive, personal circumstances change, and sometimes a different medication works better for your body.

Here's how to do it without losing progress or creating dangerous gaps in treatment.

Reasons to Consider Switching

Switching Between Drugs: No Washout Required

Good news: when switching between GLP-1 medications (semaglutide to tirzepatide, or vice versa), you generally don't need a washout period. You can take your new medication on your next scheduled injection day.

However, there's an important caveat about dosing.

Dose Conversion: There Isn't One

Semaglutide and tirzepatide are different molecules with different mechanisms (single vs. dual agonist). There's no direct 1:1 dose conversion. Even if you're on max-dose semaglutide (2.4mg), you'll typically start tirzepatide at the induction dose (2.5mg).

Switching Providers: The Transfer Protocol

Unlike a pharmacy prescription transfer (which is a phone call), telehealth prescriptions generally don't transfer between platforms. Each provider operates as a separate medical practice with its own liability. You'll need to complete a new intake with the new provider.

Here's how to do it smoothly:

Brand to Compounded (or Vice Versa)

If you're switching from brand-name Wegovy/Ozempic to a compounded semaglutide (or the reverse), you're dealing with the same molecule. This makes the switch simpler:

• Same dose: If you're on 1mg branded semaglutide, you can typically continue at 1mg compounded.
• Same schedule: Continue your weekly injection day.
• Watch for concentration differences: Compounded vials come in various concentrations. Make sure you understand how many units to draw for your dose.

The main adjustment: Pre-filled pens vs. vials require different technique. If you're moving to compounded, you'll need to learn to draw from a vial with an insulin syringe. Your pharmacy should provide instructions.

What to Expect During the Transition

If Starting a New Drug (Semaglutide ↔ Tirzepatide)

• GI symptoms may return: Even if you tolerated one medication well, the new one is different. Expect some nausea/GI adjustment.
• Appetite effects may shift: Some patients find tirzepatide provides stronger satiety; others prefer semaglutide. It varies.
• Weight loss trajectory may change: Tirzepatide generally produces more weight loss, but individual response varies.

If Same Drug, New Provider

• Should be seamless: Same medication, same dose = same effects.
• Watch for potency variation (compounded): Different compounding pharmacies may have slight variations. If you notice different effects at the "same" dose, this could be why.

When NOT to Switch

Switching isn't always the answer:

• Plateau at sub-max dose: If you're still titrating and hit a plateau, the answer is usually to increase dose—not switch drugs.
• First 2-4 weeks of side effects: Early side effects typically improve. Give it time before concluding the medication doesn't work for you.
• Because of marketing: "Newer" or "different" doesn't mean better for your specific body. Switch based on clinical reasoning, not advertising.