Tirzepatide Microdose
Compounded tirzepatide with vitamin B12, a dual GIP/GLP-1 receptor agonist, delivered at a fraction of the standard twice-weekly dose.
Medically reviewed by Dr. Jonathan Snipes, MD. Last reviewed May 6, 2026.
What It Is
This is compounded tirzepatide, not pure tirzepatide. Optimal Balance Pharmacy compounds it as tirzepatide co-formulated with cyanocobalamin (vitamin B12) in the same vial, so every injection contains both. Tirzepatide is a dual GIP/GLP-1 receptor agonist, the same active ingredient as Mounjaro® and Zepbound®. It is the identical vial we prescribe as Tirzepatide/B12, just drawn at a much smaller dose, so the vial lasts longer than standard dosing.
How It Works
By activating both GIP and GLP-1 receptors, tirzepatide supports appetite control and metabolic regulation. At microdose levels the effect is milder and slower, which suits people who want to ease in or who are side-effect sensitive. The B12 is a carrier that supports energy levels during weight loss. It does not change how tirzepatide works and does not add to weight loss on its own.
Who It's For
Adults who want a gentle entry to dual-pathway GLP-1 therapy, are sensitive to side effects, or are microdosing for appetite and metabolic support alongside diet and exercise. Not for patients with a known B12 sensitivity, who should ask their provider about the B6/glycine formulation instead.
Who Should Avoid It
Same as semaglutide: avoid with thyroid cancer history, MEN2, pancreatitis, gastroparesis, or pregnancy. Also avoid if you have reacted to cyanocobalamin (B12), since it is compounded into this vial.
Protocol & Pricing
OBP Pharmacy Price
$45/12mg
You pay pharmacy price. No markup.
Starting Dose
5 units twice weekly (0.3mg/injection, 0.6mg/week microdose)
Form
Injectable vial (2mL, 6mg/mL, 12mg total. Compounded tirzepatide + B12, not pure tirzepatide)
Dosing Protocol
5 units subcutaneous injection twice weekly. Titrate up as tolerated per provider. 5 units = 0.05mL × 6mg/mL = 0.3mg per injection (gentle microdose, 0.6mg/week). Hold or step back dose if nausea. Hydration & protein mitigate side effects.
Beyond Use Date
90 Days from compounding (USP <797>)
Optimal Balance Pharmacy assigns this date and prints it on your vial label. Always follow the label. Once a multi-dose vial is punctured, the in-use date on the label is shorter than the compounding date shown here.
Stacking Guide
Do Not Combine With
How to get Tirzepatide Microdose prescribed online
Tirzepatide Microdose is available by prescription through a licensed telehealth visit and dispensed for human use by a named 503A pharmacy. That is what separates it from research-use-only vials sold without a prescription. There is no subscription and no membership, just a one-time visit fee.
- 1
Complete a $39 medical visit. Answer a short intake about your health history and your goals for Tirzepatide Microdose. The $39 fee is the only charge RxPepsDirect collects, paid once, not a recurring subscription.
- 2
A licensed provider reviews it. A US-licensed nurse practitioner or physician reviews your intake and, if Tirzepatide Microdose is appropriate for you, writes a patient-specific prescription. The starting dose is typically 5 units twice weekly (0.3mg/injection, 0.6mg/week microdose).
- 3
The pharmacy compounds and ships it. Optimal Balance Pharmacy, a 503A pharmacy in Texas, compounds Tirzepatide Microdose and ships it pre-reconstituted by FedEx overnight in a reusable cooled case. Your fill is Injectable vial (2mL, 6mg/mL, 12mg total. Compounded tirzepatide + B12, not pure tirzepatide), and you pay the pharmacy $45/12mg at wholesale, with no clinic markup, plus a $15 flat FedEx overnight shipping fee charged by the pharmacy.
RxPepsDirect prescribes Tirzepatide Microdose in the 29 jurisdictions its medical team is licensed in. Start a $39 visit or browse the full Weight Loss & Metabolic range. Comparing services first? See how RxPepsDirect stacks up against seven other providers in our best telehealth for compounded peptides comparison.
Common questions about Tirzepatide Microdose
- What is in the Tirzepatide Microdose vial?
- Each vial contains compounded tirzepatide co-formulated with cyanocobalamin (vitamin B12), suspended together in the same solution. It is not pure tirzepatide and it is not a research-use vial. Optimal Balance Pharmacy compounds it under a 503A patient-specific prescription, and the label lists both ingredients. The vial is 2 mL at 6 mg/mL (12 mg total) for $45, plus a flat $39 medical visit fee. Every batch is tested by Eagle Analytical Services for sterility and bacterial endotoxin (USP <85>); the Certificate of Analysis is published on this page.
- Is this pure tirzepatide?
- No. This is a compounded medication, which means the pharmacy prepares tirzepatide together with vitamin B12 in one vial rather than dispensing the tirzepatide molecule on its own. Anyone selling a vial labeled pure tirzepatide for human use outside a compounding pharmacy is selling a research-use product without a prescription. The tirzepatide in this vial is the same active ingredient as Mounjaro and Zepbound, and the B12 does not change how it binds the GIP and GLP-1 receptors.
- How is this different from the standard Tirzepatide/B12 vial?
- It is the same vial. Same pharmacy, same 6 mg/mL concentration, same 12 mg total, same $45 price. The only difference is the dose your provider writes: the microdose protocol starts at 5 units (0.3 mg) twice weekly, about 0.6 mg per week, where the standard protocol starts at 25 units (1.5 mg) twice weekly. Because you draw less per injection, a single vial lasts considerably longer.
- Why is vitamin B12 in a weight loss injection?
- Cyanocobalamin acts as a soluble carrier in the formulation and doubles as an energy-supporting cofactor for patients in a caloric deficit. B12 supports red blood cell production and methylation pathways that come under load during fat loss. It is pharmacologically inert with respect to weight loss, so it does not add to your results and it does not change tirzepatide's pharmacology. The B12 carrier is a formulation choice by Optimal Balance Pharmacy, not by RxPepsDirect.
- What if I cannot tolerate B12?
- Tell your provider during the intake. Patients with a documented B12 sensitivity, an MTHFR methylation variant, or a history of reacting to cyanocobalamin should ask about the Tirzepatide/B6 + Glycine formulation instead, which uses glycine and vitamin B6 as the carrier and contains no B12. It is the same tirzepatide active ingredient. Do not order this microdose vial if you have reacted to B12 before.
- What is the starting dose for the tirzepatide microdose protocol?
- 5 units on a U-100 insulin syringe, injected subcutaneously twice weekly. On the 6 mg/mL vial, 5 units equals 0.05 mL, which is 0.3 mg per injection or roughly 0.6 mg per week. For comparison, the standard RxPepsDirect protocol is 1.5 mg twice weekly and branded Zepbound starts at 2.5 mg once weekly. Your provider confirms or adjusts the units at review and titrates up as tolerated. Always verify the concentration printed on your vial before drawing.
- How long does a microdose vial last?
- At the 5 unit starting dose, a 12 mg vial holds far more than the standard protocol would use, but the Beyond Use Date governs how long you can actually use it. The BUD is 90 days from compounding under USP <797> sterile compounding standards and is printed on every vial label. Once the vial is punctured, follow the shorter in-use BUD on your label, typically 28 days refrigerated. Refrigerate at 36 to 46 degrees Fahrenheit and do not freeze. Discard at the BUD even if solution remains.