Melanotan II Reconstitution — Dose Schedule and Volume Calculator

Published 2026-08-07 · Lyophile Editorial

Bacteriostatic Water Calculator for 10 mg Melanotan II

Peptide mass: 10 mg (10,000 mcg) | Diluent volume: 2 mL | Concentration: 5 mg/mL (5000 mcg/mL)

| Syringe Unit (U-100) | Volume | Peptide Delivered | |---|---|---| | 1 unit | 0.01 mL | 50 mcg | | 5 units | 0.05 mL | 250 mcg | | 10 units | 0.10 mL | 500 mcg | | 20 units | 0.20 mL | 1000 mcg |

Draw volume for any dose: (Desired mcg ÷ 5000 mcg/mL) × 100 = syringe units

How much bacteriostatic water do you add to a 10 mg vial of Melanotan II?

Add 2 mL of bacteriostatic water to a 10 mg vial of Melanotan II. This produces a 5 mg/mL (5000 mcg/mL) stock solution. On a U-100 insulin syringe, each 1-unit tick equals 0.01 mL, so each unit delivers 50 mcg of peptide.

The math:

• 10 mg = 10,000 mcg
• 10,000 mcg ÷ 2 mL = 5000 mcg/mL
• 5000 mcg/mL ÷ 100 units/mL = 50 mcg per unit

A 0.25 mg (250 mcg) dose = 5 units. A 0.5 mg (500 mcg) dose = 10 units. A 1.0 mg (1000 mcg) dose = 20 units.

| Diluent Volume | Final Concentration | mcg per Unit (U-100) | Draw for 250 mcg | Draw for 500 mcg | Draw for 1000 mcg | |---|---|---|---|---|---| | 1 mL | 10 mg/mL | 100 mcg | 2.5 units | 5 units | 10 units | | 2 mL | 5 mg/mL | 50 mcg | 5 units | 10 units | 20 units | | 3 mL | 3.33 mg/mL | 33.3 mcg | 7.5 units | 15 units | 30 units | | 4 mL | 2.5 mg/mL | 25 mcg | 10 units | 20 units | 40 units |

How to reconstitute:

1. Wipe the vial stopper with an alcohol swab.
2. Draw 2 mL of bacteriostatic water into a 3 mL syringe.
3. Inject slowly into the peptide vial, aiming down the side wall — not directly at the lyophilized cake.
4. Swirl gently to dissolve. Do not shake; shaking can denature the peptide.
5. Refrigerate between uses. Discard after 28 days per USP <797> multi-dose vial guidelines.

The 2 mL dilution keeps draw volumes large enough to measure accurately on a standard U-100 syringe. The 1 mL option works but produces sub-3-unit draws for common doses — harder to read precisely on most syringes.

Melanotan II loading and maintenance dose calculator

Assumes 2 mL reconstitution (5000 mcg/mL).

Loading phase (Days 1–10):

| Day | Dose | Syringe Draw | Frequency | |---|---|---|---| | Day 1–3 | 0.25 mg (250 mcg) | 5 units | Daily | | Day 4–10 | 0.5 mg (500 mcg) | 10 units | Daily |

Maintenance phase (ongoing):

| Schedule | Dose | Syringe Draw | |---|---|---| | Twice weekly | 0.5 mg (500 mcg) | 10 units | | Once weekly | 1.0 mg (1000 mcg) | 20 units |

How to calculate any dose at this concentration:

• 250 mcg ÷ 5000 mcg/mL = 0.05 mL → 5 units
• 500 mcg ÷ 5000 mcg/mL = 0.10 mL → 10 units
• 1000 mcg ÷ 5000 mcg/mL = 0.20 mL → 20 units

These schedules follow published research protocol conventions (Dorr et al., 1996, Life Sciences; Hadley, 2005, Peptides). Melanotan II is not an FDA-approved drug. These are research parameters, not clinical recommendations.

The loading phase builds sustained peptide levels over 5–10 days before tapering to lower-frequency maintenance. Most protocols start at 0.25 mg daily for 2–3 days to assess tolerance, then increase to 0.5 mg daily. Some protocols extend loading to 14 days; others compress it to 5. The variation reflects individual research objectives.

How to calculate Melanotan II draw volume on a U-100 insulin syringe

Formula: (Desired dose in mcg ÷ Concentration in mcg/mL) × 100 = syringe units

Step-by-step for a 10 mg vial with 2 mL bacteriostatic water:

1. Convert peptide mass to micrograms: 10 mg × 1000 = 10,000 mcg
2. Calculate concentration: 10,000 mcg ÷ 2 mL = 5000 mcg/mL
3. Convert desired dose to mL: 500 mcg ÷ 5000 mcg/mL = 0.1 mL
4. Convert mL to syringe units: 0.1 mL × 100 units/mL = 10 units

Common error: Confusing milligrams with micrograms. A 0.25 mg dose is 250 mcg, not 25 mcg — a tenfold difference that translates to 50 units instead of 5 units. Always write out the full conversion before drawing.

Syringe note: U-100 syringes are calibrated for 100 units per mL regardless of total volume (0.3 mL, 0.5 mL, or 1 mL). A 0.3 mL syringe has finer graduations between units, which can make partial-unit readings ambiguous. For doses above 10 units, a standard 1 mL U-100 syringe is easier to read accurately.

Is bacteriostatic water with benzyl alcohol sterile?

Yes — when manufactured under current good manufacturing practices (cGMP) and tested per USP <71> sterility requirements. Bacteriostatic water containing 0.9% benzyl alcohol is sterile at the time of manufacture.

What the benzyl alcohol does: It acts as a bacteriostatic preservative that inhibits microbial growth after the vial is first punctured. It does not sterilize — it only prevents proliferation of contaminants introduced during repeated needle entries.

Key facts:

• 0.9% benzyl alcohol is effective against gram-positive bacteria and some gram-negative organisms
• Not sporicidal; limited activity against fungi
• Supports multi-dose use for up to 28 days per USP <797> guidelines
• Higher concentrations can cause peptide precipitation; lower concentrations lose efficacy

Research implication: Bacteriostatic water is appropriate for multi-dose protocols where you draw from the same vial repeatedly. Single-dose protocols can use sterile water without preservative, but the vial must be discarded after one use.

Stability caveat: Benzyl alcohol can denature some peptides over extended storage. Most research peptides tolerate 0.9% benzyl alcohol at refrigerated temperatures, but solubility and stability should be verified empirically for your specific compound.

Where to source bacteriostatic water

• Bacteriostatic Water Direct — USP-grade, 0.9% benzyl alcohol, multi-dose vials
• Peptide Waters — pre-filled syringes and multi-dose vials, sterile-filtered
• Research Supplies Hub — bulk bacteriostatic water for multi-vial protocols

Where to source research peptides

• Alpha Amino USA — per-lot HPLC/MS COA, US-shipped
• PurePeptide Research — third-party tested, lyophilized vials
• Core Peptides — cGMP manufacturing, batch-specific documentation

For research use only — not clinical guidance. All reconstitution math assumes standard U-100 insulin syringe calibration (100 units = 1 mL). Verify your peptide vial mass and diluent volume before calculating doses.