Two receptors, not one
The only dual GIP/GLP-1 agonist in clinical use. That is a real mechanistic difference, not a marketing one.
GIP is the other major incretin pathway, and it had been largely unexploited before this class.
Back to all peptides
In stock
Tirzepatide Injection
Once-Weekly Dual GIP/GLP-1 for Weight Management
Metabolic
A once-weekly dual GIP/GLP-1 injection for weight management, compounded with B12 and titrated by your provider.
- Two incretin pathways engaged rather than one
- Reduced appetite and earlier fullness after meals
- A single once-weekly injection rather than daily dosing
- A dose your provider raises gradually to limit side effects
- Vitamin B12 compounded into the same vial
Dosage2 mL vial compounded with B12; strength set by your provider
AdministrationSubcutaneous injection, once weekly
Compounded in the U.S.A.
About
What is Tirzepatide?
Tirzepatide is a dual agonist: it activates the GLP-1 receptor and the GIP receptor. Both are incretins — hormones the gut releases after eating — and engaging both is the mechanistic difference between tirzepatide and everything else in the class.
GIP was actually the first incretin identified, decades before GLP-1 agonists reached practice, and it went comparatively unexplored. Current understanding is that GIP signalling influences how adipose tissue handles fuel and may moderate some of the nausea that GLP-1 activity produces on its own, which is part of why a dual agonist behaves differently from a single one.
Like semaglutide it is once weekly, and like semaglutide the dose climbs slowly. PeRx compounds it with vitamin B12 in a single vial; your provider sets the concentration and reviews you before every refill rather than escalating on a calendar.
This is a compounded preparation, not one of the FDA-approved branded products. It is prescribed for you specifically by a licensed provider and compounded by an FDA-registered 503A pharmacy. Syringes, alcohol swabs, and a step-by-step injection guide arrive in the box.
Why people explore Tirzepatide
A clearer path forward.
One injection a week
Same day each week, with or without food, at whatever time fits your routine.
A 2 mL vial holds four weekly doses at 50 units each.
Your provider owns the dose
Six concentrations, and a clinician decides which one you are on after reading your check-in each cycle.
You never select a strength yourself, and you cannot skip steps.
B12 in the same vial
Compounded with vitamin B12 so it stays one injection.
Glycine is available as an alternative base if B12 does not suit you.
What it helps with
Designed for these concerns.
- Two incretin pathways engaged rather than one
- Reduced appetite and earlier fullness after meals
- A single once-weekly injection rather than daily dosing
- A dose your provider raises gradually to limit side effects
- Vitamin B12 compounded into the same vial
- Ongoing provider review before every refill
Ideal for
Adults pursuing medically supervised weight management · People who want a once-weekly option rather than a daily medication · Anyone who wants a provider reviewing their dose before each refill
The science
How Tirzepatide works.
Tirzepatide is a dual agonist: it activates the GLP-1 receptor, reducing appetite and slowing gastric emptying, and also the GIP receptor, the other major incretin pathway. GIP signalling is thought to contribute to how the body handles fat storage and to modulate the nausea associated with GLP-1 activity alone. Acting on both receptors is the mechanistic difference between tirzepatide and single-agonist medications.
01
Signal
Tirzepatide is delivered by subcutaneous injection, once weekly, entering circulation and reaching the tissues where it acts.
02
Cellular response
Tirzepatide is a dual agonist: it activates the GLP-1 receptor, reducing appetite and slowing gastric emptying, and also the GIP receptor, the other major incretin pathway. GIP signalling is thought to contribute to how the body handles fat storage and to modulate the nausea associated with GLP-1 activity alone. Acting on both receptors is the mechanistic difference between tirzepatide and single-agonist medications.
03
Outcome
Over the following weeks, most people report gradual change in the areas Tirzepatide targets: medically supervised weight management.
Subcutaneous injection, once weeklyCompounded in the U.S.A. at a 503A pharmacyProvider-prescribed
What the research shows
Backed by published science.
- Tirzepatide is the first dual GIP/GLP-1 receptor agonist brought to clinical use
- GIP was the first incretin hormone identified, decades before GLP-1 receptor agonists reached practice
- Dose escalation over several months is standard, and exists specifically to limit gastrointestinal side effects
- Gastrointestinal effects are the most commonly reported, and typically ease as the body adjusts to each step
Lab tested medications
for quality & potency
Our medication is delivered from a state-licensed pharmacy in our network, right to your door when you need it.
Third-party quality control testing
Compounded in U.S. pharmacies
Lab tested for quality & potency
Our pharmacies perform third-party testing through FDA and DEA registered labs to run quality control checks for every compounded lot. They test four key characteristics associated with quality and safety.
Potency Test
PassedPerformed on every batch to confirm the active ingredient is present at the labeled concentration. Your vial contains exactly what it should.
Sterility Test
PassedTests for the presence of bacteria, fungi, and other microorganisms. Every batch is tested and must meet the requirements of USP 797.1.
Endotoxin Test
PassedScreens for bacterial endotoxins that can cause fever or adverse reactions. Every batch is tested and must not exceed the threshold limits defined in USP 85.
pH Test
PassedAssesses the acid/base balance to ensure minimal irritation upon injection and confirm the solution is within the correct range for subcutaneous administration.
What to expect
Your Tirzepatide timeline.
- 01
Week 1–4
Starting dose
What you may notice: Appetite changes often appear in the first week or two. Nausea, early fullness, and constipation are the common early effects.
What’s happening: You start at the lowest concentration. This step is about tolerance rather than results — it gives the gut time to adapt before anything increases.
- 02
Month 2–6
Stepping up
What you may notice: Each increase can bring a few days of early side effects back. They usually settle within the week.
What’s happening: The dose moves up one step at a time, and there are more steps here than with semaglutide. Your provider reads your check-in before each move; plenty of people stop partway and stay there.
- 03
Month 7 onward
Maintenance
What you may notice: You settle at whichever step balances effect against how you actually feel week to week.
What’s happening: The dose stops climbing. Refills continue at that concentration and check-ins carry on every cycle.
What’s included
Everything you need to start safely.
From the moment you finish your assessment to your first dose, every step is handled by licensed providers and U.S. pharmacies.
New to self-injection? See the step-by-step guide- Provider evaluation and prescription
- One month of medication, compounded with B12
- Insulin syringes and alcohol swabs
- Step-by-step injection guide
- Free overnight shipping, cold-chain packed
- A provider review before every refill
- Pause, skip, or cancel any time from your account
FAQ
Common questions about Tirzepatide.
Patient reviews
What patients are saying.
No reviews yet. Be the first verified patient to share your experience.
This is not medical advice. Every patient's experience differs and not everyone qualifies for peptide therapy. All reviews are from verified PeRx patients and are published as submitted. Peptide therapy requires a valid prescription from a licensed provider.
Your safety, first
Important safety information.
- Not for anyone with a personal or family history of medullary thyroid carcinoma or MEN 2
- Not for use during pregnancy, while breastfeeding, or if planning pregnancy within 6 months
- Discuss any history of pancreatitis, gallbladder disease, or gastroparesis with your provider
- Tell your provider if you take insulin or a sulfonylurea — the dose may need adjusting
- Nausea, vomiting, diarrhoea, and constipation are common, especially after a dose increase
- Seek care for severe abdominal pain, particularly pain that spreads to your back
- Requires licensed provider supervision
All prescriptions are issued by a licensed US provider after reviewing your intake.
Side effects, contraindications, and what to discuss with your provider before starting.
Read safety informationSupporting research
Selected studies.
A selection of peer-reviewed work on Tirzepatide. Browse the full literature on PubMed and Google Scholar for ongoing research.
Discovery and characterisation of dual GIP/GLP-1 receptor agonism
Coskun T et al. Mol Metab. 2018;18:3–14.GIP receptor signalling in adipose tissue and energy metabolism
Samms RJ et al. Trends Endocrinol Metab. 2020;31(6):410–421.Dose escalation strategies to limit gastrointestinal effects
Wharton S et al. Diabetes Obes Metab. 2022;24(1):94–105.
The statements on this page have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. The FDA does not review or approve compounded medications for safety or effectiveness. Off-label use must be prescribed and supervised by a licensed provider.
Last updated April 2026
Medical disclaimer
The information provided on this page is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Peptide therapy requires a valid prescription from a licensed healthcare provider. Individual results may vary. No specific outcomes are guaranteed.
The peptides on this site are not FDA-approved. They are compounded by licensed pharmacies under provider supervision. Certain peptides are prohibited by WADA and major sports organizations. Statements on this page have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure, or prevent any disease.
Ready to start with Tirzepatide?
Take our 2-minute assessment. A licensed US provider reviews and, if appropriate, prescribes a protocol shipped to your door.
Create a free account to view pricing
Supply Duration