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." I know that is what people type, because it is what I typed. My assumption was that somewhere there is an official table that says 1.7 mg of one equals such-and-such of the other, and that my prescriber was working from it.

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?" Changing drugs restarts the titration weeks, so a rough patch is likely even if you were steady before.

I am a mother who reads labels, not a 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.

On the compounded side the switch can cost nothing at all. Clume Health charges the same $259 whichever molecule you pick, which is genuinely unusual, and SexyMD prices by how long you commit rather than by drug. Andrew Meds publishes both ladders side by side, and VevaRX sells tirzepatide only as a three-month plan.