Wegovy vs Zepbound
Wegovy and Zepbound are the two branded pens approved for weight management, and they are built on different ingredients: semaglutide in Wegovy, tirzepatide in Zepbound. This page compares the pair on approved uses, maintenance doses, the trial results with the context they need, side effects, and list prices. It deliberately does not declare a winner, because the trial averages cannot make that call for an individual, and tolerability and coverage usually decide in real life.
The two weight management pens at a glance
| Detail | Wegovy | Zepbound |
|---|---|---|
| Active ingredient | Semaglutide, a GLP-1 receptor agonist | Tirzepatide, which acts on both GIP and GLP-1 receptors |
| Approved for | Weight management | Weight management, and obstructive sleep apnea in adults with obesity |
| How often | One injection, once a week | One injection, once a week |
| Max weekly dose | 2.4 mg, the label maintenance dose | 15 mg maximum; label maintenance doses are 5 mg, 10 mg or 15 mg |
| Trial result | In STEP 1, people lost an average of 14.9 percent of body weight over 68 weeks | In SURMOUNT-1, people on the 15 mg dose lost an average of 20.9 percent of body weight over 72 weeks |
| About list price per month | About $1,350 | About $1,060 |
Read the trial row with care. STEP 1 and SURMOUNT-1 were separate trials, run in different groups of people over different lengths of time. They were not a head to head comparison, so the two percentages cannot be used to say that one medicine beats the other for any individual person.
How they differ in practice
The ingredients differ: Wegovy is semaglutide, acting on the GLP-1 receptor; Zepbound is tirzepatide, acting on GIP and GLP-1 receptors. The shapes of the schedules differ too. Wegovy climbs through fixed steps, 0.25, 0.5, 1 and 1.7 mg, to one maintenance dose of 2.4 mg from week 17 onward. Zepbound starts at 2.5 mg and climbs in 2.5 mg steps, but its label names three maintenance doses, 5, 10 and 15 mg, so where a person settles is part of the plan rather than a single target. The Wegovy dosage chart and the Zepbound dosage chart show both schedules in full.
The milligram numbers, 2.4 against 15, say nothing about strength. They are different molecules, and each schedule was built and tested around its own ingredient.
Side effects compared
Both labels are led by gastrointestinal effects: nausea, vomiting, diarrhea and constipation, most common while doses are rising, and both carry the same family of serious warnings. Neither label lets you predict which pen a particular person will tolerate better; that is usually discovered in the first months of dose climbing, which is one reason prescribers sometimes keep a dose steady for longer. The Wegovy side effects page and the Zepbound side effects page cover each profile in plain language.
Who each is usually prescribed for
Both labels are for weight management in people who meet the label criteria. Zepbound carries one additional approval, for obstructive sleep apnea in adults with obesity, which can matter when both conditions are being treated. Beyond that, prescribers weigh treatment history, other conditions, tolerability during any earlier GLP-1 use, and which product a person's insurance will actually cover, because an uncovered pen helps no one.
Switching between them
Switching between Wegovy and Zepbound is one of the more common changes in weight management care, usually after a plateau, limiting side effects, or a coverage change. It is always a prescriber decision, never a self switch. The new pen starts from its own published schedule, your prescriber sets the timing of the changeover, and the two are never overlapped. Bring the reason for the switch to the appointment, because a plateau and a tolerability problem can point to different answers.
Frequently asked questions
Which works better, Wegovy or Zepbound?
There is no head to head trial of the two pens, so no honest verdict exists. The published averages, 14.9 percent in STEP 1 for Wegovy's ingredient and 20.9 percent in SURMOUNT-1 for Zepbound's ingredient at its top dose, come from separate trials with different people and durations. Individuals vary widely around any average, and the pen you can tolerate and get covered is the one that can work for you.
Why is Wegovy more expensive than Zepbound?
Each manufacturer sets its own list price. Wegovy lists at about $1,350 a month and Zepbound at about $1,060. Those are list prices before insurance; what you pay depends on your plan's coverage for weight management medicines, which varies a great deal.
Is Zepbound approved for sleep apnea as well?
Yes. As well as weight management, the Zepbound label covers obstructive sleep apnea in adults with obesity. Wegovy's label does not include sleep apnea. If both conditions apply to you, that extra approval is worth raising with your prescriber.
How long does each pen take to reach its maintenance dose?
Wegovy follows fixed four week steps and reaches its 2.4 mg maintenance dose from week 17 onward at the standard pace. Zepbound climbs in 2.5 mg steps of at least four weeks; its maintenance dose can be 5, 10 or 15 mg, so the climb can end at different points, with the top dose reached around week 21 at the fastest standard pace.
Can I switch from Wegovy to Zepbound?
Yes, switching is common, but it is a prescriber decision, never a self switch. Your prescriber will start you on the Zepbound schedule, set the changeover timing, and make sure the two pens are not overlapped. The milligram doses do not convert between the two ingredients.