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N-Acetyl Semax_Dosage, benefits & legal status

Also known as NA Semax, Acetyl Semax, N-acetyl semax peptide

Published September 12, 2026

Semax with one stabilising tweak, sitting between plain Semax and the amidate version.

Focus & brainSemax variantResearch only
Common vial size30 mg
Dose0.2 up to 0.4 mg per day
Frequency1-2x daily
RouteNasal spray
StatusResearch only
CycledTaken in courses, usually 10 to 14 days, with breaks between

Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.

01

What is N-Acetyl Semax?

Plain language first. The technical label stays, but it never stands alone.

Overview

It aims to do the same focus-and-memory job as Semax, through the same BDNF pathway, while lasting a little longer per dose.

The technical version

N-Acetyl Semax is Semax with an acetyl group attached to the N-terminus, added to slow enzymatic breakdown.

What it's used for

Focus, memory, and mental clarity, as a somewhat longer-lasting version of Semax.

02

How does N-Acetyl Semax work?

What it does in the body, and where.

This is Semax with one chemical modification, an acetyl group at the N-terminus, added to slow its breakdown.

  1. 01
    Same BDNF mechanism as Semax
    Nothing about the target changes.
  2. 02
    The acetyl group resists enzymes
    Which should extend how long it stays active, though this has never been measured formally for this variant.
  3. 03
    Less studied than Semax
    Semax has decades of Russian clinical use behind it. This variant is largely a vendor product.
Where it acts
Brain

Where this compound is thought to act.

03

What else is it used for?

Each use below carries its own evidence level. Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.

  • Focus, memory, and mental clarity, the same job as SemaxResearch only
  • Lasting a little longer per dose than plain Semax, which is the claimed reason for the acetyl groupResearch only

The published record

Research index

0

Papers and trials about N-Acetyl Semax

Europe PMC was searched on 12 September 2026 and returned nothing.

Counted from Europe PMC indexing, not read by a person.

N-Acetyl Semax vial rendering
Compound field notes

At a glance

Four things to know about N-Acetyl Semax

01

Evidence

Research only

02

Category

Brain, mood and sleep

03

Common vial

30 mg

04

Half-life

Not established

04

How much, and do you cycle it?

The range, and whether you take breaks.

0.2 up to 0.4 mg per day, 1-2x daily. Taken in courses, usually 10 to 14 days, with breaks betweenCommunity practice

Same course pattern as Semax, which it is a variant of. No controlled study has compared courses against continuous use.

Compare this against the whole library →

05

How long does it stay in the body?

The half-life, and where the figure comes from.

Not establishedCommunity practice

This variant has not been characterised at all. Even plain semax rests on Russian-language work that reports effects rather than clearance.

Not yet traced to a primary source.

You can compare this against the whole library to see where it sits.

06

What does it cost?

Typical dose and cost, in plain numbers.

N-Acetyl Semax is not injected

It is taken nasal spray.

Cost per month
Cost per dose
Typical dose
200 mcg–400 mcg / dayCommunity practice
No published human study establishes this dose. It comes from vendor and community practice, and several compounds in this group share suspiciously identical round numbers across retailer sites.
What it costs

N-Acetyl Semax starts at $42.00 across 8 vendors, typically $2.28 – $6.90 per mg.

12 listings, last read Sep 12, 2026. Shipping and card fees are not included.

See all 12 listings →
07

How do you store it?

Before mixing, and after.

Fridge after opening. Use within about 30 days.

Store sealed N-Acetyl Semax in the fridge. Once opened, keep it upright in the fridge and plan to finish it inside roughly 30 days. Keep it out of light and do not freeze the liquid.

08

What are the side effects and cautions?

Known cautions and warnings for this compound.

Who should avoid it

Check these before anything else.
  • No formal contraindications established outside Russia
  • Pregnancy

Stop and get help

These are emergencies. Seek care.
  • No serious adverse events have been reported at studied doses of Semax itself
  • Signs of an allergic reaction

Common effects

Expected, and usually mild.
  • Mild nasal irritation, from nasal use
  • Occasional short-lived headache
  • Possible difficulty sleeping if taken late in the day
  • No tolerance, dependence, or withdrawal has been documented for Semax
  • Almost everything known about this variant is extrapolated from Semax, not measured directly

Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.

09

Is N-Acetyl Semax approved?

And where the numbers on this page come from.

No. N-Acetyl Semax is not approved for any use, anywhere. It is sold labelled for laboratory research only, and there is no legal route to buy it for human use.

What has happened recently

We have not yet written a full regulatory note for this compound. The status above is current as of the date shown.

Guides for this compound

Sources

  • FDA, bulk drug substances nominated for use in compounding under section 503A, updated 14 May 2026(2026)
    This compound is not Semax. It is an acetylated derivative, and FDA treats even a free base and its salt as different active ingredients with potentially different safety profiles. It appears in none of the three categories on this list, which is the comprehensive record of what has been proposed for pharmacy compounding since the process opened in 2013, so absence from all three categories means no one has ever put this compound forward.

Last reviewed 12 September 2026