To work out the volume for Semax you need two numbers: how many milligrams (mg) are in your vial, and how many millilitres (mL) of liquid you added to mix it. From those, the math gives you the concentration and then the amount to measure. This page is educational only — it is not medical advice, and it does not recommend a dose. Always follow your prescriber and pharmacist.
Semax is a short peptide derived from a fragment of ACTH, developed in Russia and studied in relation to attention, memory and BDNF. It is most often prepared as a nasal spray or drops rather than an injection.
Semax is not FDA-approved in the United States; it was developed and is registered in Russia. On 24 July 2026 the FDA’s Pharmacy Compounding Advisory Committee voted to recommend Semax for the 503A bulk drug substances list — but that vote is non-binding, the agency’s own reviewers had recommended against it, and nothing has formally changed. Those reviewers specifically flagged possible anticoagulant activity and potentiation of amphetamines as safety signals. If you take a blood thinner or a stimulant medication, that is a conversation to have with your physician.
Because Semax is normally prepared as a nasal spray or drops rather than an injection, it is commonly mixed with sterile saline, which is gentler on the nasal lining than plain water. Some preparations use bacteriostatic water instead. Either way, the choice of liquid does not change the concentration math below — that depends only on the milligrams in the vial and the millilitres you add. Which liquid to use is a pharmacist question.
Nasal preparations are measured in millilitres, drops or sprays rather than syringe units, so the useful number is the concentration:
(1 mg = 1000 mcg. A drop from a standard dropper is roughly 0.05 mL and a metered nasal spray is commonly about 0.1 mL, but both vary by device — measure yours rather than assuming.)
Example 1 — example only; your vial may differ, confirm with your pharmacist. A 5 mg vial mixed with 5 mL gives 5 × 1000 ÷ 5 = 1000 mcg per mL. Measuring 300 mcg purely as arithmetic would be 300 ÷ 1000 = 0.3 mL — roughly 6 drops at 0.05 mL each. A neutral illustration of the math, not a recommended amount.
Example 2 — example only. The same 5 mg vial mixed with only 2 mL gives 2500 mcg per mL, so the same 300 mcg becomes 0.12 mL — less than half the liquid. The powder did not change; only the water did.
You will see various Semax amounts quoted online and in supplier literature. They are mentioned here strictly as educational context — they are not a recommendation, and what is appropriate for you is a decision for your physician. Do not take a number from a calculator or a forum. Use this tool only to check the mixing arithmetic for the vial in front of you.
This is a mixing-math and concentration tool, not a dosing tool, and it cannot tell you whether a compound, an amount, or a product is appropriate or safe for you. A few honest reminders:
Pepathary is a free, offline, educational tracker. It does not sell, source, or recommend any product, compound, or dose.
It depends entirely on how concentrated your mixed vial is. For example only: a 5 mg vial in 5 mL is 1000 mcg per mL, so 300 mcg is 0.3 mL; the same vial in 2 mL is 2500 mcg per mL, so the same 300 mcg is 0.12 mL. Run your own vial's numbers, and confirm any amount with your physician — this is mixing math, not a dose recommendation.
That is a question for your pharmacist and for the instructions supplied with your vial — this page does not tell you how much to add. What it does show is how to turn whatever amount you added into a usable number. More liquid makes a more dilute mix (a larger volume per amount), less liquid makes a more concentrated one.
No. Semax is not FDA-approved in the United States. An FDA advisory committee voted on 24 July 2026 to recommend it for the 503A compounding list, but the vote is non-binding and FDA reviewers had recommended against it, flagging possible anticoagulant activity and potentiation of amphetamines.
No. The calculation depends only on the milligrams in the vial and the millilitres of liquid you add. Whether that liquid is bacteriostatic water, sterile saline or dilute acetic acid, the arithmetic is identical. Which diluent to use is a pharmacist question about solubility and sterility, not a math question.
No. This is a reconstitution (mixing-math) tool that converts your vial mg and liquid mL into a concentration and a measurable amount. It does not recommend, select, or endorse a dose, and the example numbers are neutral illustrations of arithmetic only. Always follow your physician's and pharmacist's instructions.