Wegovy vs Zepbound vs compounded GLP-1s: what's the difference?

At a glance (as of September 2026)

The Wegovy pill and Foundayo are FDA-approved GLP-1 pills for weight management, alongside the Wegovy and Zepbound injections. The approved uses below are summarized from each product's FDA labeling. In every case, the drug is used together with a reduced-calorie diet and increased physical activity.

All four brand products are prescription medicines, and each label carries a boxed warning about thyroid C-cell tumors.

Semaglutide: Wegovy injection and Wegovy pill

The injection and the pill share one FDA label, revised June 2026.

Wegovy injection is approved:

• to reduce the risk of major cardiovascular events (cardiovascular death, heart attack or stroke) in adults with established cardiovascular disease and either obesity or overweight
• to reduce excess body weight and maintain weight reduction long term in adults and children 12 and older with obesity, and in adults with overweight plus at least one weight-related condition
• to treat noncirrhotic MASH with moderate to advanced liver fibrosis in adults, under accelerated approval

The injection now includes a higher-strength pen sold as Wegovy HD.

Wegovy tablets are approved in adults for the cardiovascular risk reduction and weight-management uses. Novo Nordisk announced the approval on December 22, 2025.

The label says not to use Wegovy with other semaglutide-containing products or other GLP-1 receptor agonists. It also sets specific administration conditions for the tablets, including taking them on an empty stomach. Follow your prescriber's instructions and the Medication Guide.

Tirzepatide: Zepbound

Zepbound's label describes it as a GIP receptor and GLP-1 receptor agonist, meaning it acts on two hormone receptors rather than one. It is approved:

• to reduce excess body weight and maintain weight reduction long term in adults with obesity, or adults with overweight and at least one weight-related condition
• to treat moderate to severe obstructive sleep apnea in adults with obesity

It comes as a single-dose pen, a single-dose vial, and a multi-dose KwikPen. The label says not to use it with other tirzepatide-containing products or any GLP-1 receptor agonist.

The newer pill: Foundayo

Foundayo (orforglipron) is a daily GLP-1 receptor agonist tablet from Eli Lilly. FDA approved it on April 1, 2026 for weight reduction and long-term maintenance in adults with obesity, or adults with overweight and at least one weight-related condition.

Its label says it can be taken with or without food, and that it should not be used with another GLP-1 receptor agonist. Its active ingredient, orforglipron, is different from semaglutide and tirzepatide. FDA described it as a new molecular entity.

Compounded versions

Compounded products are made by pharmacies or outsourcing facilities, not by the drug's manufacturer. Key facts from FDA:

• No FDA review. Unapproved versions do not undergo FDA's review for safety, effectiveness and quality before they are marketed.
• Not generics, and not the "same." FDA says companies cannot claim that compounded products are generic versions of, or the same as, FDA-approved drugs. They also cannot claim that compounded products use the same active ingredient or are clinically proven.
• Ingredient concerns. FDA says some compounders have used semaglutide salt forms, such as semaglutide sodium and semaglutide acetate. These are different active ingredients from the one in approved drugs, and FDA knows of no lawful basis for using them. Retatrutide and cagrilintide cannot be used in compounding at all.
• Dosing errors and adverse events. FDA has received reports of adverse events, some requiring hospitalization, that may be related to dosing errors with compounded semaglutide. As of May 31, 2026, it had received 990 adverse event reports for compounded semaglutide and more than 730 for compounded tirzepatide.
• Tighter limits since the shortages ended. With the shortages resolved (tirzepatide on December 19, 2024, and semaglutide on February 21, 2025), FDA's policy restricts compounding copies of the approved drugs. Exceptions are limited, such as a prescriber's documented determination that a change makes a significant difference for an individual patient.

For more on the legal status, see is compounded semaglutide or tirzepatide still legal?

How each is obtained

Brand-name products: you need a prescription from a licensed clinician, filled by a licensed pharmacy. That can be a retail or mail-order pharmacy, or a manufacturer's own self-pay program. Prices and programs are covered in brand-name self-pay options.

Compounded products: FDA advises that compounded drugs be used only when a patient's medical needs cannot be met by an FDA-approved drug. They should come with a prescription from a licensed clinician, filled at a state-licensed pharmacy.

Using this comparison

This table compares legal and label facts only. Different trials enrolled different people and measured results in different ways, so results from separate studies are not directly comparable. Whether any of these medicines fits you depends on your health history, other medications, coverage and preferences. That decision belongs with a licensed clinician who can examine you and follow up.