Tirzepatide Dosing: Chart, Calculator & Titration Schedule
The complete tirzepatide dosing guide — standard chart, mg-to-units conversion, an interactive calculator, vial reconstitution math, and the answers to every "how many units" question Google sends to this site.
01 Tirzepatide dosing calculator
Enter your dose, vial concentration, and syringe type — the calculator returns the exact draw in units and mL, plus your next titration step. Works for compounded vials and brand-name pens.
Tirzepatide Dosing Calculator
Tool · 1 of 3Convert your weekly tirzepatide dose between mg, units, and mL. Get your titration timeline and next escalation step.
- Draw (units)
- 50
- Volume (mL)
- 0.50 mL
- Frequency
- Once weekly
- Next escalation
- 7.5 mg (week 5)
*For informational purposes only. Not a substitute for medical advice. Always follow your prescriber's instructions. Tirzepatide is a prescription medication.
02 The standard tirzepatide dosing chart
Tirzepatide is a once-weekly subcutaneous injection. The dosing schedule below is identical for Mounjaro (type 2 diabetes), Zepbound (weight loss and sleep apnea), and most legitimate compounded products. It comes directly from the FDA prescribing information.
| Phase | Dose | Duration | Purpose |
|---|---|---|---|
| Initiation | 2.5 mg | 4 weeks | Tolerance only — sub-therapeutic |
| First therapeutic | 5 mg | 4 weeks | First true weight-loss dose |
| Step up | 7.5 mg | 4 weeks | Optional maintenance for many |
| Maintenance | 10 mg | 4 weeks | Common long-term dose |
| Step up | 12.5 mg | 4 weeks | Optional |
| Maximum | 15 mg | Indefinite | Max FDA-approved dose |
After the 2.5 mg starter month, most prescribers use a "5 mg first, then assess" approach. If side effects are mild and you're losing weight steadily, you can stop titrating up — there's no rule that says you must reach 15 mg. The right maintenance dose is the lowest one that gives you the appetite suppression and weight loss you need.
03 Tirzepatide titration schedule (visual)
Below is the full 21-week titration timeline. Each step is held for at least 4 weeks before the next dose increase. You can pause titration at any maintenance dose.
Standard FDA-label titration. Real-world schedules often pause at 5 mg, 7.5 mg, or 10 mg as long as weight loss continues.
How fast can you titrate?
The label says 4 weeks per step. In practice, three patterns exist:
- Standard (4-week steps) — the default. Best tolerance, slowest progression to therapeutic dose. Reach 10 mg by week 13.
- Slow (6–8 week steps) — for patients with significant nausea, slow weight loss benefit, or those happy at a lower dose. Reach 10 mg by week 17–25.
- Fast (2–3 week steps) — sometimes used in telehealth when patients are tolerating well and want faster appetite control. Significantly more GI side effects.
04 Tirzepatide mg-to-units conversion
The most-asked tirzepatide question on the internet: how many units is X mg? The answer depends entirely on the concentration of your vial. Brand-name Mounjaro and Zepbound pens are pre-dosed — there is no math. Compounded tirzepatide arrives as a multi-dose vial, so you draw the right number of units on a U-100 insulin syringe.
Conversion table at common compounded concentrations
| Dose (mg) | At 5 mg/mL | At 10 mg/mL | At 15 mg/mL |
|---|---|---|---|
| 2.5 mg | 50 units (0.50 mL) | 25 units (0.25 mL) | 17 units (0.17 mL) |
| 5 mg | 100 units (1.00 mL) | 50 units (0.50 mL) | 33 units (0.33 mL) |
| 7.5 mg | 150 units (1.50 mL) | 75 units (0.75 mL) | 50 units (0.50 mL) |
| 10 mg | 200 units (2.00 mL) | 100 units (1.00 mL) | 67 units (0.67 mL) |
| 12.5 mg | 250 units (2.50 mL) | 125 units (1.25 mL) | 83 units (0.83 mL) |
| 15 mg | 300 units (3.00 mL) | 150 units (1.50 mL) | 100 units (1.00 mL) |
Three common compounded concentrations are shown: 5 mg/mL (10 mg vial + 2 mL BAC water — gives larger draws, easier to measure), 10 mg/mL (10 mg vial + 1 mL BAC water — most common all-purpose), and 15 mg/mL (30 mg vial + 2 mL BAC water — used for higher doses). Always verify the concentration printed on your vial.
The formula
Units to draw = (target dose in mg ÷ vial concentration in mg/mL) × 100
Example: target 7.5 mg, vial concentration 10 mg/mL → (7.5 ÷ 10) × 100 = 75 units. The "× 100" comes from the U-100 insulin syringe convention (1 mL = 100 units). If you use a U-50 syringe instead, multiply by 50.
05 Vial concentrations & reconstitution math
Compounded tirzepatide is shipped as a sterile lyophilized powder in a sealed vial. You add bacteriostatic water (BAC water — sterile water with 0.9% benzyl alcohol as a preservative) before the first use. The amount of BAC water you add determines the final concentration, which determines how many units = how many mg.
| Vial size | BAC water | Concentration | Units per mg (U-100) |
|---|---|---|---|
| 10 mg | 2 mL | 5 mg/mL | 20 units / mg |
| 10 mg | 1 mL | 10 mg/mL | 10 units / mg |
| 15 mg | 1.5 mL | 10 mg/mL | 10 units / mg |
| 20 mg | 2 mL | 10 mg/mL | 10 units / mg |
| 30 mg | 2 mL | 15 mg/mL | 6.67 units / mg |
| 30 mg | 3 mL | 10 mg/mL | 10 units / mg |
Why concentration matters
A higher concentration (15 mg/mL) gives you a smaller draw — easier on insulin syringes but harder to measure precisely at low doses. A lower concentration (5 mg/mL) gives you a larger, more measurable draw but uses more BAC water and means you'll fill the syringe further at higher doses.
The two most common compounded concentrations are 5 mg/mL (used by most large compounders for 2.5–10 mg doses) and 10 mg/mL (used for 12.5–15 mg doses where the larger draw at 5 mg/mL becomes inconvenient).
For the full reconstitution walkthrough — including BAC water selection, vial-prep technique, storage, and the dedicated reconstitution calculator — see the compounded tirzepatide guide.
06 Missed dose protocol
Tirzepatide has a long half-life (about 5 days), so a slightly delayed dose is rarely a crisis. The official FDA guidance:
Within 4 days of scheduled dose
Take the missed dose as soon as you remember. Resume the regular weekly schedule from your original dose day.
More than 4 days late
Skip the missed dose entirely. Take the next dose on your usual day. Do not double up — that significantly increases the risk of severe nausea and vomiting.
Restarting after a longer break
If you've been off tirzepatide for more than 3 weeks (e.g., a vacation, supply gap, or prior auth delay), most prescribers will restart you at a lower dose than where you stopped. Returning to 10 mg or 15 mg without a re-titration period is a recipe for severe GI side effects. Common protocol: drop one or two steps and re-titrate every 1–2 weeks.
07 Maximum dose & what 15 mg actually does
Fifteen milligrams once weekly is the highest FDA-approved tirzepatide dose. In the SURMOUNT-1 trial, the 15 mg arm produced a mean weight loss of 20.9% over 72 weeks — the largest figure in any phase 3 obesity trial of any drug to date.
However, going from 10 mg to 15 mg only adds about 1.4 percentage points of average weight loss (from 19.5% to 20.9%) — a modest gain. Side effects, on the other hand, climb sharply: nausea rates jump from ~28% at 10 mg to ~33% at 15 mg, and discontinuation rates roughly double. For most patients, 10 mg is the sweet spot between effect and tolerability.
Can you take more than 15 mg?
No. There is no published clinical trial data on tirzepatide doses above 15 mg, and there is no medical or compounding pharmacy that legitimately offers higher doses. If you're at 15 mg and not losing weight, the answer is generally not a higher dose — it's a re-evaluation of diet, sleep, NEAT, alcohol, sleep apnea, thyroid status, or whether you should consider switching to a different drug class entirely (like the next-generation triple agonist retatrutide).
Get your prescribed dose delivered.
Skip the prior auth, the pharmacy line, and the brand-name markup. Compounded tirzepatide at every dose strength, shipped monthly from licensed US pharmacies.
Start Your Consult→08 Tirzepatide dosing FAQ
Start at 2.5 mg once weekly for 4 weeks (this is a tolerance dose, not therapeutic). Then increase to 5 mg, then 7.5 mg, then 10 mg, then 12.5 mg, then 15 mg, holding each dose for 4 weeks before stepping up. The maximum FDA-approved dose is 15 mg weekly. Most patients land on a maintenance dose between 5 mg and 12.5 mg.
It depends on the concentration. At the most common compounded concentration of 5 mg/mL, 2.5 mg = 0.5 mL = 50 units on a U-100 insulin syringe. At 10 mg/mL, 2.5 mg = 0.25 mL = 25 units. At 15 mg/mL, 2.5 mg = 0.167 mL ≈ 17 units. Always verify the concentration printed on your vial before drawing.
At 5 mg/mL concentration: 100 units (1.0 mL). At 10 mg/mL: 50 units (0.5 mL). At 15 mg/mL: 33 units (0.33 mL). Use the dosing calculator above to convert any combination of dose and concentration.
At 5 mg/mL: 50 units = 0.5 mL = 2.5 mg. At 10 mg/mL: 50 units = 0.5 mL = 5 mg. At 15 mg/mL: 50 units = 0.5 mL = 7.5 mg. Units alone are meaningless without the vial concentration.
The maximum FDA-approved dose is 15 mg once weekly. There is no clinical evidence that doses above 15 mg produce additional weight loss, and side effects increase non-linearly above 12.5 mg.
The starting dose for both Mounjaro and Zepbound is 2.5 mg once weekly for 4 weeks. This dose is sub-therapeutic for weight loss — it exists only to let your gut adapt to the GLP-1/GIP signal. Going straight to 5 mg dramatically increases nausea and vomiting.
Some patients respond well at 2.5 mg or 5 mg and choose to stay there long-term — especially if appetite suppression is adequate. This is a discussion to have with your prescriber. Lower doses come with fewer side effects but generally less weight loss.
Standard FDA labeling: every 4 weeks. Some prescribers extend the interval to 6–8 weeks if you're tolerating poorly or losing weight rapidly on a lower dose. Faster titration (every 2 weeks) is sometimes done with telehealth providers but increases GI side effects.
If you remember within 4 days of your scheduled dose, take it as soon as possible and resume your regular weekly schedule. If more than 4 days have passed, skip the missed dose entirely and take the next dose on your normal day. Do not double up.
Yes — the active ingredient and the dosing schedule are identical. The difference is the delivery: brand Zepbound/Mounjaro come in pre-filled auto-injector pens; compounded comes in multi-dose vials that you draw up with an insulin syringe. The mg dose is the same; only the math changes.
Related guides
Compounded tirzepatide →
Reconstitution calculator, BAC water, and concentration math.
Microdosing tirzepatide →
Sub-therapeutic dosing for sensitive responders or maintenance.
How to inject →
Step-by-step technique, injection sites, and pen vs vial.