Weight Loss Peptide

Semaglutide Dosage Calculator

Calculate compounded semaglutide reconstitution and weekly injection dose. Includes titration schedule from 250 mcg to 2,400 mcg.

Calculate your semaglutide dose

Concentration
Units to draw
mL to draw
Weeks per vial
Visual syringe guide
units to draw

Semaglutide dose escalation

Semaglutide requires a gradual dose increase (titration) to minimize gastrointestinal side effects. Never start at the full dose.

PhaseWeeksWeekly DoseUnits (3mg/1.5mL, 100u)Purpose
Month 11-4250 mcg12.5 unitsInitiation — adjust to medication
Month 25-8500 mcg25 unitsFirst escalation
Month 39-121,000 mcg50 unitsTherapeutic range begins
Month 413-161,700 mcg85 unitsIncreased efficacy
Month 5+17+2,400 mcgUse 5mg vialMaximum dose (Wegovy)

Quick Reference: 3mg Vial + 1.5mL BAC Water

Weekly DoseUnits (100u syringe)Units (50u syringe)mL to DrawWeeks/Vial
250 mcg12.5 units6.3 units0.125 mL12 weeks
500 mcg25 units12.5 units0.25 mL6 weeks
1,000 mcg50 units25 units0.50 mL3 weeks
1,700 mcg85 units42.5 units0.85 mL~1.7 weeks

How to use compounded semaglutide

Semaglutide is a GLP-1 receptor agonist originally developed for type 2 diabetes (Ozempic) and later approved for chronic weight management (Wegovy). Compounded semaglutide is a pharmacy-prepared version that requires reconstitution before use.

Step-by-Step Reconstitution

  • Step 1: Gather supplies — semaglutide vial, bacteriostatic water, insulin syringe (100-unit preferred), and alcohol swabs
  • Step 2: Clean both vial tops with alcohol swabs
  • Step 3: Draw 1.5mL of bacteriostatic water (for a 3mg vial) into the syringe
  • Step 4: Insert needle into semaglutide vial, inject water slowly down the inside wall
  • Step 5: Gently swirl until fully dissolved — solution should be clear and colorless
  • Step 6: Label the vial with reconstitution date
  • Step 7: Refrigerate at 2-8°C. Use within 28 days

Injection Instructions

Semaglutide is injected subcutaneously once per week, on the same day each week. Recommended injection sites: abdomen (2 inches from navel), front of thighs, or upper arms. Rotate injection sites each week. Inject at any time of day, with or without food.

Managing Side Effects

  • Nausea: Eat smaller meals, avoid fatty/fried foods, stay hydrated. Usually subsides within 2-3 weeks of each dose increase
  • Constipation: Increase fiber and water intake. Consider a stool softener if needed
  • Injection site reactions: Rotate sites, let alcohol dry completely before injecting
  • If side effects are severe: Stay at current dose for an extra 4 weeks before increasing. Consult your healthcare provider

Semaglutide vs Ozempic vs Wegovy

Ozempic and Wegovy are brand-name semaglutide products in pre-filled pens. Compounded semaglutide contains the same active ingredient but comes as lyophilized powder requiring reconstitution. The key difference is cost — compounded semaglutide is typically 60-80% less expensive than brand-name versions.

Week-by-week titration schedule

Semaglutide dosing follows a gradual titration protocol to minimize gastrointestinal side effects. The standard schedule increases the dose every 4 weeks, allowing the body to adjust before moving to the next level. Never skip titration steps — rapid dose escalation significantly increases the risk of nausea, vomiting, and other GI side effects.

PhaseWeeksWeekly DosePurposeCommon Side Effects
Initiation1-40.25 mg (250 mcg)Adjustment period — not a therapeutic doseMild nausea in ~20% of users
Step 25-80.5 mg (500 mcg)First therapeutic dose. Appetite reduction beginsNausea, reduced appetite
Step 39-121.0 mg (1,000 mcg)Standard maintenance dose for many usersGI symptoms typically diminishing
Step 413-161.7 mg (1,700 mcg)Enhanced dose if weight loss plateaus at 1.0 mgPossible return of mild nausea
Step 517+2.4 mg (2,400 mcg)Maximum dose (Wegovy equivalent)Most side effects resolved by this point

Titration tips

  • Stay longer at any step if needed: If side effects are bothersome at a given dose, remain at that level for an extra 4 weeks before increasing. There is no rush to reach the maximum dose.
  • Many people stay at 1.0 mg: Not everyone needs to reach 2.4 mg. If you are seeing satisfactory results at a lower dose with fewer side effects, discuss maintaining that dose with your provider.
  • Inject on the same day each week: Pick a consistent day (many choose Monday or Friday). If you miss a dose by less than 5 days, take it as soon as possible. If more than 5 days have passed, skip that week and resume on your regular schedule.
  • Track your progress: Record your weight, side effects, and appetite changes weekly. This data helps your healthcare provider make informed dosing decisions.

Use our calculator above to determine exactly how many syringe units to draw for each titration step based on your vial concentration. For a comparison with the newer dual-mechanism alternative, see our tirzepatide dosage calculator.

Managing semaglutide side effects

Most semaglutide side effects are gastrointestinal and tend to improve over time as the body adapts. Understanding how to manage them can make the difference between completing or abandoning the titration protocol.

Side EffectFrequencyOnsetManagement Strategies
Nausea~44% of usersUsually within first 1-2 weeks of each dose increaseEat smaller, more frequent meals. Avoid greasy, spicy, or heavy foods. Ginger tea or peppermint may help. Eat slowly and stop when satisfied — not full.
Diarrhea~30% of usersFirst 2-4 weeks at new doseStay hydrated with electrolytes. Avoid high-fiber foods temporarily. Consider probiotics. Usually resolves without intervention.
Constipation~24% of usersCan occur at any dose levelIncrease water intake (aim for 2-3 liters daily). Add fiber gradually. Magnesium citrate (200-400 mg) before bed can help. Regular physical activity promotes motility.
Injection site reactions~5% of usersImmediately after injectionRotate between abdomen, thigh, and upper arm. Let alcohol swab dry completely before injecting. Inject at room temperature (remove from fridge 15-30 min prior).
Fatigue~11% of usersFirst few weeks, usually temporaryEnsure adequate protein intake (0.8-1g per pound of body weight). Stay hydrated. Reduced caloric intake can contribute — don't under-eat.
Headache~14% of usersEarly in treatmentOften related to reduced food/fluid intake. Maintain hydration and regular meal timing.

When to contact your healthcare provider

  • Severe or persistent vomiting lasting more than 24 hours
  • Signs of pancreatitis: severe abdominal pain radiating to the back
  • Signs of hypoglycemia: shakiness, sweating, confusion (especially if taking insulin or sulfonylureas concurrently)
  • Vision changes or signs of thyroid issues (neck swelling, difficulty swallowing)
  • Gallbladder symptoms: sharp pain in the upper right abdomen after eating

Compounded vs brand-name semaglutide

With growing demand and limited brand-name supply, compounded semaglutide has become a widely used alternative. Understanding the differences is essential for making an informed decision.

FactorBrand-Name (Ozempic/Wegovy)Compounded (503A/503B Pharmacy)
Active ingredientSemaglutide (FDA-approved formulation)Semaglutide (same molecule, different salt form in some cases)
FormPre-filled pen, ready to injectLyophilized powder requiring reconstitution
Cost (monthly)$900-1,350 without insurance$150-400 from compounding pharmacies
Dosing precisionPre-set doses (click-based pen)Requires manual calculation — use our calculator above
RegulationFDA-approved, manufactured under cGMPState Board of Pharmacy regulated (503A) or FDA-registered (503B)
PrescriptionRequiredRequired
AvailabilitySubject to shortagesGenerally available

Whether you use brand-name or compounded semaglutide, proper reconstitution technique is critical for dosing accuracy. Our reconstitution guide covers the complete process step by step. For the general peptide dosing reference, visit our peptide calculator homepage.

Important: Semaglutide is a prescription medication. This calculator is for educational purposes only. Always work with a licensed healthcare provider for proper dosing and medical supervision.

Semaglutide frequently asked questions

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