Overview
Mounjaro and Zepbound.
Weekly shot that hits two appetite hormones at once.
Got people up to ~22% weight loss at the high dose.
What It Does
FDA-approved dual GIP/GLP-1 agonist, gold standard for weight loss.
Co-activates GIPR (appetite + insulin + fat-cell effects) and GLP-1R (satiety + gastric slowing + glucagon suppression).
Reconstitution
| Vial Size | BAC Water / Solvent | Concentration |
|---|---|---|
| 10 mg | + 0.50 mL | 20 mg/mL |
| 15 mg | + 0.75 mL | 20 mg/mL |
| 20 mg | + 1 mL | 20 mg/mL |
| 30 mg | + 1.5 mL | 20 mg/mL |
| 40 mg | + 2 mL | 20 mg/mL |
| 50 mg | + 2.5 mL | 20 mg/mL |
| 60 mg | + 3 mL | 20 mg/mL |
| 80 mg | + 4 mL | 20 mg/mL |
| 100 mg | + 5 mL | 20 mg/mL |
Reconstitution Calculator
Enter the vial amount and diluent volume to calculate concentration. If you already have a target amount, you can also convert it to liquid volume and syringe markings. This tool does not recommend a target amount.
Enter a target amount you already have and select the syringe capacity.
Mathematical reference only. The calculator does not determine an appropriate target amount. Syringe capacity only changes the maximum volume that fits.
Protocol
| Phase | Frequency | Amount | Notes |
|---|---|---|---|
| Weeks 1–4 | 2.5 mg/wk | 12.5u | |
| Weeks 5–8 | 5 mg/wk | 25u | |
| Weeks 9–12 | 7.5 mg/wk | 37.5u | |
| Weeks 13–16 | 10 mg/wk | 50u | |
| Weeks 17–20 | 12.5 mg/wk | 62.5u | |
| Weeks 21+ | 15 mg/wk | 75u |
Ongoing per FDA labels; no scheduled off-cycle. Discontinue ≥1 month before planned pregnancy. After March 19, 2025 the FDA bars compounded tirzepatide without documented clinical difference; sourcing now mostly grey-market research suppliers. In 2026 the FDA also proposed excluding sema/tirz/liraglutide from the 503B bulks list (comments due Jun 29, 2026). FDA indications: T2D (Mounjaro); chronic weight management (Zepbound); OSA in obesity (Zepbound, Dec 2024). MASH: Phase 3 ongoing, NOT FDA-approved.
Women lose more than men at the same dose but report more GI (start lower). In PCOS they improve cycles, lower free testosterone and raise ovulation; a real unplanned-pregnancy risk. Stop before conceiving. Tirzepatide also cuts oral-birth-control absorption, use a backup method for ~4 weeks after each step up. Men: In men, excess fat lowers testosterone; GLP-1 raises total testosterone, SHBG and gonadotropins as weight drops, and improves sperm and erectile function; and preserves fertility, unlike TRT (which suppresses spe Women lose more than men at the same dose but report more GI (start lower). In PCOS they improve cycles, lower free testosterone and raise ovulation; a real unplanned-pregnancy risk. Stop before conceiving. Tirzepatide also cuts oral-birth-control absorption, use a backup method for ~4 weeks after each step up. Men: In men, excess fat lowers testosterone; GLP-1 raises total testosterone, SHBG and gonadotropins as weight drops, and improves sperm and erectile function; and preserves fertility, unlike TRT (which suppresses sperm).
Handling & Stacking
- Freeze-dried: -4°F.
- Reconstituted: 36–46°F.
- Best used within 28 days.
- No clear reconstituted-potency data (the pen label gives an in-use date, not potency), so defer to the 28-day sterility limit; commercial pens follow their own pen date.
- Appetite reduction from week 1; better GI tolerance than semaglutide. ~20% average weight loss at 72 weeks.
- SURMOUNT-5 head-to-head (72 wks): tirzepatide 20.2% vs semaglutide 13.7%, ~47% greater relative loss.
- Supply math 50mg → 7 vials | 60mg → 6 | 80mg → 4 | 100mg → 4 vials (21-wk @ 15 mg × 1/wk)
FDA Label vs Community Dosing
| Approach | Ramp / dose (weekly) | Philosophy |
|---|---|---|
| FDA, Zepbound (weight loss) | 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg, +4 wks per step | 2.5 mg is a starting dose, not therapeutic; escalate for maximum effect (max 15 mg). |
| FDA, Mounjaro (type-2 diabetes) | Same ramp; maintenance 5, 10, or 15 mg | Glycemic control; may skip 5→10 / 10→15 if tolerated. |
| Community | Same ramp, but many hold at 5–10 mg; microdose 2.5 | Titrate to effect, step up only if weight loss stalls. for tolerance Bottom line: the FDA ramp targets the maximum dose; community practice holds at the lowest effective dose (often 5–10 mg) to minimize nausea and cost. Both use the same 4-week step cadence. Nutrition & timing: protein first (1.2–1.6 g/kg/day), carbs last, to protect the lean mass these drugs burn with fat; lift 2–3×/wk + creatine 5 g/day. Stop eating ~3 h before bed (slowed emptying + lying flat drives reflux). Low intake favors mild ketosis, so a low-carb/keto approach pairs well; push water (2.5–3 L/day) + electrolytes, both dehydrate. |
| Contraindications | Personal or family history of medullary thyroid carcinoma (MTC) or MEN 2; personal/family history of any thyroid cancer Personal history of pancreatitis (any cause) Pre-existing gastroparesis or significant gastric motility disorder; severe GERD, scleroderma, or other delayed-emptying conditions Prior serious hypersensitivity to the compound or excipients Pregnancy and lactation; discontinue 1 month before planned conception. History of cholelithiasis / gallbladder disease. Active or pre-existing diabetic retinopathy; eating-disorder history; CKD stage 4–5 | |
| Warnings | Acute pancreatitis: discontinue if suspected (severe abdominal pain radiating to back) Acute gallbladder disease; diabetic-retinopathy progression; acute kidney injury from GI-related volume depletion (highest during escalation) Severe GI: ileus, obstruction, severe constipation, fecal impaction. Anaphylaxis/angioedema reported. Tachycardia (1–4 bpm). Aspiration risk under anesthesia. | |
| Drug interactions | Delayed gastric emptying affects oral absorption (levothyroxine, oral contraceptives, warfarin); separate timing. Insulin / secretagogues: reduce at initiation. Do not combine with other GLP-1 agonists. | |
| Labs | Baseline: BMP/CMP, CBC, HbA1c, lipid panel, TSH, pregnancy test. BMP at every dose escalation and any time GI side effects cause >24h reduced intake. HbA1c at 3 + 6 mo; lipids at 6 mo; repeat eGFR if dehydration. Lipase if abdominal pain. Drop hsCRP / routine calcitonin., Out of range? Rising glucose/HbA1c = blood sugar creeping toward diabetes (recheck, tighten diet); a falling eGFR = kidney strain, usually dehydration (hydrate, hold the dose). | |
| Stop criteria | Creatinine rise >0.3 mg/dL or eGFR drop >20%: hold, rehydrate. Severe abdominal pain: evaluate for pancreatitis. Vision changes: ophthalmology. Persistent vomiting >48h: hold. New neck mass / hoarseness / dysphagia: thyroid workup. | |
| Patient education | acute kidney injury on GLP-1s is from dehydration, not the drug. Target 2.5–3 L water/day; hold next dose for any day of vomiting/diarrhea/reduced food; resume same level after 24h recovery. Required during any GLP-1 cycle: protein 1.2 g/kg IBW/day (1.6 if training), resistance training 2–3×/wk, creatine 5 g/day; else 25–40% of weight lost is lean mass with rapid regain. Eat slowly, stop at first fullness. Inform any anesthesiologist before procedures (aspiration risk). Discontinue ≥1 month before planned pregnancy (shorter washout than semaglutide). Pen sharing prohibited even with a new needle. | |
| References | seekpeptides · rxlist · researchdosing · peptidedosages · DailyMed · GLP-1 sex differences · Jensterle 2020 |
