Prescription Priority: How Prescribers Decide Between Wegovy, Zepbound, and Compounded

The Decision Isn't Random: Here's the Framework

When your prescriber decides which GLP-1 to prescribe, they're running through a clinical decision tree that weighs efficacy data, your insurance coverage, your medical history, and your practical preferences. It's not one-size-fits-all, and a good prescriber will explain why they're recommending one option over another.

The three main buckets: FDA-approved semaglutide (Wegovy), FDA-approved tirzepatide (Zepbound/Foundayo), and compounded versions of either molecule. Each has distinct trade-offs that matter for different patients.

Wegovy vs. Zepbound: The Clinical Comparison

Mechanism: Wegovy is a GLP-1 receptor agonist. Zepbound is a dual GLP-1/GIP receptor agonist — it activates two receptors instead of one. This dual mechanism is associated with greater average weight loss in clinical trials.

Efficacy data: In head-to-head and cross-trial comparisons, tirzepatide (Zepbound) produces approximately 20-25% average body weight loss at maintenance doses, compared to approximately 15-17% for semaglutide (Wegovy). Individual results vary significantly — some patients respond better to one than the other.

Side effect profiles: Both cause GI side effects (nausea, vomiting, diarrhea, constipation) during titration. The rates are roughly comparable, though some patients tolerate one better than the other. The only way to know which side effect profile suits you is to try them.

Dosing: Both are weekly injections. Wegovy titrates from 0.25 mg to 2.4 mg over 16-20 weeks. Zepbound titrates from 2.5 mg to 15 mg over a similar timeline. Oral formulations of semaglutide (Rybelsus/oral Wegovy) are also available but have lower bioavailability and require strict fasting protocols.

Additional indications: Wegovy has cardiovascular risk reduction data (SELECT trial). Zepbound has sleep apnea data. Both may inform prescribing for patients with these conditions.

When Prescribers Choose Compounded

Compounded GLP-1 medications enter the decision tree primarily when cost or access barriers make FDA-approved options impractical:

No insurance coverage: When a patient doesn't have insurance coverage for brand-name GLP-1s and can't afford $900-1,300/month cash pricing, compounded versions at $149-$399/month become the primary option for access.

FDA-approved supply issues: During supply shortages (which have affected both Wegovy and Zepbound at various points), compounded versions from 503A or 503B pharmacies provide an alternative supply source.

Custom dosing needs: Compounding pharmacies can prepare doses that aren't available in the standard titration packs — useful for patients who need very gradual titration or maintenance doses between standard increments.

The trade-off with compounded: these medications are not FDA-approved. They're legally prescribed, legally compounded, and clinically appropriate — but they haven't undergone the same rigorous manufacturing and testing process as Wegovy or Zepbound. Responsible prescribers explain this distinction clearly.

How to Have This Conversation With Your Prescriber

Don't wait for your prescriber to bring up the options — ask directly. Here's a framework:

"Given my insurance coverage and health profile, what would you recommend and why?" This invites your prescriber to explain their reasoning rather than just writing a script.

"What are the differences I'd notice between Wegovy and Zepbound?" This focuses on practical patient experience rather than abstract clinical data.

"If cost weren't a factor, what would you prescribe? And how different is the compounded version?" This separates the clinical recommendation from the financial reality, helping you understand whether you're compromising on treatment quality or just on branding.

"What does the switch process look like if the first one doesn't work?" Some patients need to try both semaglutide and tirzepatide before finding the one that works best for them. Understanding the switch protocol upfront prevents frustration if the first choice doesn't produce the expected results.