Cognitive and neuro

Semax

A Russian prescription drug, judged without its own literature

What it actually is

Semax is a lab made copy of a small piece of a natural body chemical. In Russia it is a real prescription medicine, sold as drops you put up your nose, and it is used there after strokes. In the United States it is not approved for anything, and the drops are not what most people here are buying.

What it is supposed to do

The popular story is that it raises a growth chemical in the brain called brain derived neurotrophic factor, which helps brain cells survive and connect to each other. That rise was measured in rats given it up the nose, and the biggest number people quote, an eight fold jump, came from brain cells in a dish rather than a living animal. Nobody has measured that chemical in a living person's brain, the United States drug regulator concluded the mechanism is not established, and the strongest independent work points somewhere else entirely, at copper binding and at opioid receptors.

What people take it for

People buy it as a brain drug, for focus and for recovery, and the community routine circulating online is a convention rather than anything a trial produced. The three conditions it was formally put in front of the regulator for were poor blood flow to the brain, migraine, and a facial nerve pain condition called trigeminal neuralgia.

The dose question

What circulates: 500 to 3,000 mcg, usually injected
What was studied: 800 to 8,000 mcg, up the nose; The Russian 0.1 percent label

Below the label range and by a different route. Almost everything sold here is injected; every published study went intranasally.

Reported because it is what people use. Nothing here recommends any amount.

How long it lasts

Nobody has measured this in a person. There are no published human measurements of how long it lasts in the body by any route, nose or needle.

Route studied

Up the nose, as drops

Route used

Injected under the skin, at home

How to check you have the right molecule

Three molecules are sold under nearly the same name, so compare the weight on the lab report. Plain Semax weighs 813.9 and carries the identifier number 80714-61-0. N Acetyl Semax weighs 856.0. N Acetyl Semax Amidate weighs 855.0 and carries the identifier number 2920938-90-3. A weight reading tells you instantly whether you are holding plain Semax, because the 42 unit gap is enormous. It cannot tell you which of the two acetylated versions you have, because they sit about 1 unit apart and an ordinary report is not fine enough to split that. So also read the identifier number beside the name: vendors and at least one database put 2920938-90-3 on products labelled N Acetyl Semax, and that number belongs to the amidate, meaning the label and the number name two different things.

Walked through on two real certificates in how to read a certificate of analysis.

What people get wrong

The expensive mistake is treating N Acetyl Semax and N Acetyl Semax Amidate as upgraded, stronger versions of the original. Nothing at all has been published on them, and the one study that looked at adding that acetyl group found it wiped out a protective effect the plain version had on cells, which is the opposite of what the marketing claims.

What is known about harm

The Russian label for the weaker nasal drops says it is not to be used in acute psychotic states, in conditions that come with anxiety, or in anyone with a history of seizures. In mice it made the dopamine surge from amphetamine larger, which the United States regulator flagged as a possible abuse concern, and it raised a second flag about a blood thinning effect, drawn from a single conference summary with no full paper behind it. The injected route that almost everyone here uses has zero published human safety data of any kind.

The arithmetic

Semax is sold in 30 mg vials. Mixing errors put people an order of magnitude off using a perfectly good vial, and the arithmetic is simple enough to check yourself.

Vial	Water	Concentration	In 10 units
30 mg	1 mL	30 mg/mL	3 mg
30 mg	2 mL	15 mg/mL	1.5 mg
30 mg	3 mL	10 mg/mL	1 mg

10 units is 0.1 mL on a U-100 insulin syringe, whatever is in it. For any other combination, or to see the arithmetic worked out, use the calculator.

Everything on this page is a summary. The citations, the studies and the reasoning live in the full entry.

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