I Went Looking for the Wegovy-to-Zepbound Conversion Chart. There Isn't One.

The search I typed

“Switching from Wegovy to Zepbound dosage chart” is an understandable search. I would want a clear answer too, but a table found online should not be mistaken for a manufacturer’s conversion rule. The first question is what the prescribing information actually provides, and which decisions still require a prescriber.

So I went and read the actual prescribing information for Zepbound, Wegovy and Ozempic, front to back, looking for it.

It is not there. Not hedged, not buried in a footnote — there is no dose conversion between semaglutide and tirzepatide anywhere in the labeling. I searched all three documents for "transition" and for "equivalent dose" and got nothing at all^1,2,3.

The one place Wegovy's label does discuss switching is section 2.5, and it covers moving between Wegovy injection and Wegovy tablets² — the same drug in two forms, not a different drug.

That surprised me more than it probably should have. Millions of people are moving between these medications and the manufacturers have not published a way to translate the dose.

Why there isn't one

Once I thought about it, it makes sense. These are not the same molecule. Semaglutide acts on one receptor; tirzepatide acts on two. Milligrams of one are not a unit you can restate in milligrams of the other, any more than you can convert cups of flour into cups of sugar because both are cups.

Any chart you find online is somebody's rule of thumb. It might be a reasonable one, and an experienced prescriber has a feel for this. But nobody should hand you a number and imply the FDA is behind it, and I would want to know which of those two I was being given.

What the labels do say

Both are explicit about starting, and neither carves out an exception for people arriving from another drug.

Zepbound starts at 2.5 mg once weekly for four weeks. The label is pointed about this one: 2.5 mg is for treatment initiation and is not approved as a maintenance dosage. After four weeks it goes to 5 mg, then rises in 2.5 mg steps with at least four weeks at each, to a maintenance dose of 5, 10 or 15 mg. Fifteen is the ceiling¹.

Wegovy starts at 0.25 mg once weekly for four weeks, then titrates every four weeks — the available strengths run 0.25, 0.5, 1, 1.7, 2.4 and 7.2 mg — with 2.4 mg as the usual maintenance dose².

Read plainly, that means the labeled route onto a new drug is its own starting dose and its own ladder. Whether your prescriber shortens that for you is a clinical judgment about your tolerance and history. It is not something the label authorizes, and it is worth asking her to say out loud which she is doing.

The instruction I did not expect

This is the part I am glad I found, because it is a safety point rather than a dosing one.

Wegovy's label states that using it alongside other semaglutide-containing products or with any other GLP-1 receptor agonist is not recommended².

So these do not overlap. You are not meant to finish out a box of one while beginning the other, or bridge a gap by taking both in the same week. If you are switching because of a shortage or a coverage change, that is exactly the situation where doubling up feels harmless, and the label says otherwise.

The timing question nobody answers either

I looked for a required washout — how long to leave between the last dose of one and the first of the other — and did not find one in the labeling.

What I did find is the missed-dose rule, which at least tells you how the weekly rhythm is meant to work. For Zepbound, a missed dose can be taken within four days (96 hours); past that you skip it and resume on schedule. The injection day can be moved as long as there are at least three days (72 hours) between doses¹.

What I would ask

• "What are you basing the starting dose on?" A label ladder, or her own experience. Both are legitimate. Only one is written down.
• "Am I starting at the bottom, and if not, why not?" Both labels titrate from their own starting dose to limit gastrointestinal side effects^1,2. Skipping steps is a trade against tolerability.
• "When exactly do I stop the old one?" Given that overlapping is not recommended², I would want that as a date, not a vague instruction.
• "What if the side effects are worse?" Ask which symptoms to report and what would delay the next increase; tolerating one medicine does not guarantee the same response to another.

I am reading labels, not acting as your clinician, and none of this is medical advice. But if a chart appears in your search results with confident numbers on it, it is worth knowing it did not come from the people who make the drug.

A switch can also change the price, formulation and billing term. The reviews of Clume Health, SexyMD, Andrew Meds and VevaRX describe their different offers. I would request the full new prescription and recurring quote rather than assume either the dose or the price transfers from the old plan.