Drug facts

Compounded tirzepatide with B12, B6 or glycine

By David Chen·Editor·Reviewed September 2026

What is in the approved product¹

Zepbound’s label ends the question of what the approved drug contains, because section 11 lists it. A single-dose pen or vial holds the dose of tirzepatide and sodium chloride, sodium phosphate dibasic heptahydrate and water for injection, with acid or base added only to adjust the pH. The multi-dose vial and KwikPen add the preservatives a vial you draw from several times needs — benzyl alcohol, glycerin and phenol.

That is the complete list. There is no cyanocobalamin, no pyridoxine, no glycine and no niacinamide in it, at any strength, in any presentation. So when a seller sells “tirzepatide with B12”, the B12 is not part of tirzepatide as approved; it is the pharmacy’s addition.

What the add-ins are³

B12

Cyanocobalamin, a vitamin. It is also an approved drug in its own right, sold as an injection — which matters for the next section.

B6

Pyridoxine, also a vitamin with its own approved injection. That label’s indication is pyridoxine deficiency — from poor diet, certain drugs, or inborn errors of metabolism.

Glycine

An amino acid. It has no role in any tirzepatide label.

Why compounders add them⁴

The label gives no clinical reason for an add-in. The law gives a practical one. Since FDA declared the tirzepatide shortage over, a state-licensed pharmacy compounding under section 503A may not regularly make drugs that are “essentially copies of a commercially available drug product.” The statute carves out one exception, and its wording is the whole story:

the term “essentially a copy of a commercially available drug product” does not include a drug product in which there is a change, made for an identified individual patient, which produces for that patient a significant difference, as determined by the prescribing practitioner, between the compounded drug and the comparable commercially available drug product.

A vial that differs from Zepbound — an extra ingredient, an unusual strength — can look like that kind of change. FDA addressed this directly.⁵ Its April 2026 statement says it may consider a product that combines the GLP-1 with “another API, such as vitamin B12 (cyanocobalamin), to be essentially a copy” when it is given the same way as the approved products and “the amounts of semaglutide and vitamin B12 in the compounded drug product are within 10% of the strengths of the respective commercially available drug products.” FDA’s example names semaglutide; the test it applies is written for any compounded drug, tirzepatide included.

So an add-in is not a loophole by itself. What the law cares about is whether a prescriber determined that you needed the difference. The rest of the legal position — including the four-prescription policy most large sellers rely on — is on is compounded tirzepatide still legal?

Why your vial may look different²

Zepbound’s label describes the approved solution as “clear, colorless to slightly yellow.”¹ Cyanocobalamin, by its own label, “appears as dark, red crystals or as an amorphous or crystalline, red powder.” A compounded vial with B12 in it may therefore not look like the approved product at all, and that alone is not a sign that something is wrong.

What the color should be is a question only the pharmacy that made your vial can answer, because it depends on what went into it and how much. Ask before your first dose rather than guessing. And if a vial arrives warm, the storage rules apply whatever its color — see how long compounded tirzepatide lasts out of the fridge.

Sellers in this index selling an add-in version⁶

At least 8 sellers in this index sell a tirzepatide product whose own page names an add-in — 6 of them B12. We did not record ingredients for every seller, so this is a floor, not a count of the whole market.

• Bayan Health — tirzepatide with B6
• Brello Health — tirzepatide with B6
• CeliaRx — tirzepatide with B12
• EllieMD — tirzepatide with B12
• June Health — tirzepatide with B12 and Glycine
• Lumora — tirzepatide with B12
• RxPepsDirect — tirzepatide with B12
• Stealth Health — tirzepatide with B12 and Glycine

Each seller’s page shows what it actually bills per calendar month, and the product page the price was read from.

What to ask the pharmacy

• How much of each ingredient is in one milliliter? You need the tirzepatide concentration to measure a dose at all — see units, milligrams and milliliters — and the add-in’s amount is part of what makes the preparation what it is.
• Why is the add-in in my prescription? If the answer is a documented reason that applies to you, that is the exception the law describes. If it is a standard recipe every patient gets, it is not.
• What is the beyond-use date, and what color should it be? Both belong to the pharmacy, and both should be on or with your label.

If you want to know what compounded tirzepatide is in the first place — and what a pharmacy is and is not permitted to make — start with what compounded tirzepatide is.