Semaglutide Dosage Chart: mg to Units for Compounded Vials, Week by Week

Semaglutide is prescribed in milligrams, but a compounded vial is drawn up with an insulin syringe marked in units. Getting from one to the other takes one line of math, and it's the step where the FDA has seen people go badly wrong. The charts below give you the weekly schedule, the units for each dose at three common vial strengths, and the reverse lookup if your instructions are written in units.

What is the standard semaglutide titration schedule?

There's no FDA-approved schedule for compounded semaglutide, because compounded semaglutide isn't an FDA-approved drug. Prescribers almost always follow the Wegovy label, which starts low and steps up every four weeks to limit nausea and other stomach side effects¹.

The label lets prescribers stop at 1.7 mg if 2.4 mg isn't tolerated, and suggests delaying the next step by four weeks if a dose is hard to tolerate¹. Many compounded programs move more slowly than this, and some hold people at a lower dose for months. Slower is allowed. Faster than every four weeks isn't what the label describes. On this schedule, the STEP 1 trial reported an average weight loss of 14.9% at 68 weeks on 2.4 mg, versus 2.4% on placebo².

How many units is each dose at 1, 2.5 and 5 mg/mL?

On a U-100 insulin syringe, 100 units is 1 mL. So:

Units to draw = (your dose in mg ÷ your vial's mg/mL) × 100

Here is that formula worked out for every step of the schedule at three concentrations compounding pharmacies commonly use. Find the strength printed on your own vial. If yours isn't here, do the math with your number.

Anything over 100 units won't fit in a standard 1 mL syringe, which is why 1 mg/mL vials are rarely used past the 1 mg step. At 5 mg/mL the starting dose is just 5 units, a very small mark to read on a 1 mL syringe. A 0.3 mL or 0.5 mL insulin syringe has larger markings for small doses. Ask your pharmacy which size suits your dose.

How many mg is 10, 20 or 40 units?

If your instructions give you a number of units, this is the reverse lookup. The same number of units is a very different dose depending on the vial.

Take 20 units. From a 2.5 mg/mL vial it's 0.5 mg, the week-5 dose. From a 5 mg/mL vial it's 1 mg, double that. Same syringe mark, twice the drug.

What dosing errors has the FDA reported?

In July 2024 the FDA warned about overdoses linked to compounded semaglutide in multiple-dose vials. Most reports involved people drawing more than the prescribed dose, in some cases five to 20 times the intended amount. Some needed medical care or a hospital stay, with nausea, vomiting, fainting, dehydration, pancreatitis and gallstones among the reported problems. In several cases, people told to inject 5 units (0.05 mL) drew up 50 units instead. The agency also noted that concentrations vary between compounders, and even within one compounder's products³.

Three habits prevent most of this:

• Read the mg/mL on every new vial, even a refill from the same pharmacy, and redo the math.
• Write your unit number down and check it against the syringe before you inject.
• If the number is very different from your last vial's, call the pharmacy before you inject.

What about the 7.2 mg dose?

The Wegovy label now allows adults who have tolerated 2.4 mg for at least four weeks to move up to 7.2 mg once weekly if more weight loss is needed¹. In the STEP UP trial, 7.2 mg produced 18.7% average weight loss at 72 weeks, compared with 15.6% on 2.4 mg. Stomach side effects were more common on the higher dose (70.8% vs 61.2%), as was dysesthesia, an abnormal skin sensation (22.9% vs 6.0%)⁴.

At 5 mg/mL, 7.2 mg is 144 units (1.44 mL), more than a 1 mL syringe holds. A compounded 7.2 mg dose needs a stronger vial or two draws, and that's a conversation for your prescriber and pharmacist, not something to work out alone.

How long does a vial last at each step?

Vial sizes vary. As an example, a 2 mL vial at 2.5 mg/mL holds 5 mg of semaglutide in total.

The arithmetic isn't the whole answer. Each compounded vial has a discard or beyond-use date on its label, and that date can arrive before the vial is empty, especially at the low starting doses. Don't use a vial past it.

What does compounded semaglutide cost per month?

As of October 2026, the median published starting price for compounded semaglutide across the more than 360 programs we track was $178 a month. Some charge one flat price at every dose, while others raise the price as the dose climbs. Before you sign up, ask what you'll pay at 1.7 mg and 2.4 mg, not just in month one. Cheapest semaglutide compares current programs, and the cost calculators let you model a full year.

For the brand-name schedule side by side with Zepbound's, see the GLP-1 dosing and titration schedule. For tirzepatide, use the tirzepatide dosage chart. For the injection itself, see how to inject semaglutide. If you're curious about staying below the labeled doses, what the evidence says about microdosing covers it. Not medical advice: confirm your vial's concentration and your dose with your prescriber or pharmacist, and see our medical disclaimer.