Question 1

How much bacteriostatic water should I add?

Accepted Answer

The amount of water is flexible and depends on your preferred injection volume. Adding 2 mL to a 5 mg vial gives a concentration of 2,500 mcg/mL, which is a good balance between precision and injection volume. Adding 1 mL gives a more concentrated solution (5,000 mcg/mL) with smaller injection volumes. Adding 3 mL gives a more dilute solution (1,667 mcg/mL) that is easier to measure small doses precisely. Choose whatever makes your target dose convenient to measure on your syringe.

Question 2

How do I read insulin syringe units?

Accepted Answer

A standard U-100 insulin syringe has 100 units per 1 mL. Each small tick mark typically represents 1 or 2 units depending on the syringe size. For a 1 mL (100 unit) syringe, the 50-unit line is the halfway point (0.5 mL). For a 0.5 mL (50 unit) syringe, each tick is usually 1 unit. To convert mL to units, multiply by 100. So 0.1 mL = 10 units, 0.25 mL = 25 units.

Question 3

How long does a reconstituted vial last?

Accepted Answer

Reconstituted peptides mixed with bacteriostatic water typically remain stable for 28-30 days when refrigerated at 2-8 degrees C (36-46 degrees F). The bacteriostatic water contains 0.9% benzyl alcohol as a preservative, which prevents bacterial growth. Never freeze reconstituted peptides, and always store them upright in the refrigerator. Peptides mixed with sterile water (without preservative) should be used within a few days.

Question 4

What is the difference between mg and mcg?

Accepted Answer

One milligram (mg) equals 1,000 micrograms (mcg). Peptide vials are typically labeled in milligrams (e.g., 5 mg, 10 mg), while doses are often prescribed in micrograms (e.g., 100 mcg, 250 mcg, 500 mcg). To convert: 5 mg = 5,000 mcg. This calculator handles the conversion automatically when you enter the vial amount in mg and the dose in mcg.

Peptide Dosage Calculator

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