BRAIN, FOCUS & MOOD COMPARISON

The Nootropic Comparison

Semax and Selank are the originals: Russian peptides with clinical approval at home and decades of study behind them. N-Acetyl Semax and Adamax are newer modifications of Semax, researched for the same outcomes but with no clinical studies of their own. They are not interchangeable, and their evidence is far from equal. See how they fit together, find the one that matches the outcome you are studying, compare them side by side, then see how a nasal spray and a subQ injection differ.

HOW THEY FIT TOGETHER

One design, two branches

Semax and Selank were built the same way: a short fragment of a natural peptide, finished with the same stabilizing tail (Pro-Gly-Pro) so it lasts long enough to study. The fragment decides what each one is studied for. The analogues then change Semax further.

The Semax branchBuilt on a fragment of ACTH, a pituitary stress hormone · focus and cognition

SemaxThe original; Russian clinical approval

↓ plus an acetyl group, to resist breakdown

N-Acetyl SemaxLonger-acting; no trials of its own

↓ plus an adamantane group, meant to reach the brain more easily

AdamaxNewest design; no published studies

The Selank branchBuilt on tuftsin, a natural immune-system peptide · calm and mood

SelankCalm focus; Russian clinical approval

Selank is the only peptide here built on a different fragment, which is why it is studied for calm and stress resilience rather than drive.

Why the analogues score lower. N-Acetyl Semax and Adamax keep Semax's core, so they are researched for the same outcomes, but the Russian clinical work was run on Semax itself. Our framework never lets a compound inherit its parent's evidence, so each is scored on its own record: N-Acetyl Semax has laboratory stability data and a research-use following, and Adamax has no published study at all.

PICK BY RESEARCH GOAL

Which one fits your research?

Each option has its own job. Find the outcome you are studying, then read its details below.

If you are studying…	Start with
Focus, memory, and mental drive, with the strongest evidence behind it	SemaxThe member of the family with a clinical record
Calm focus, stress resilience, and steadier mood	SelankThe calming branch, with its own clinical record
Semax's focus research, with a longer window per dose	N-Acetyl SemaxResists breakdown; no trials of its own
The newest Semax design, in early-stage research	AdamaxNo published studies yet

COMPARE THE PROFILES

How they stack up

Highlight one option to see its relative research emphasis across focus and calm, and the research record behind it. Ratings show relative research emphasis and typical research-use profile—not measured effect sizes, not guaranteed results, and not head-to-head trial rankings.

Focus & Cognition Attention, memory, and mental-drive emphasis

Semax

Primary focus

N-Acetyl Semax

Primary, longer-acting

Adamax

Primary, unmeasured

Selank

Calm focus

Calm & Stress Resilience Anxiety, stress, and mood-steadiness emphasis

Selank

Primary focus

Semax

Secondary

N-Acetyl Semax

Secondary

Adamax

Unmeasured

Research Record Published studies and research-use track record (per Evidence Framework)

Semax

Russian clinical use

Selank

Russian clinical use

N-Acetyl Semax

Research use

Adamax

Too new

Dose context. Semax and N-Acetyl Semax are typically researched at about 400 mcg daily, and Adamax at the same 400 mcg, since no study has set an amount of its own. Selank is typically about 500 mcg daily. The bars are not dose-matched, and none of this is a dosing recommendation.

Focus. Semax carries the clinical record here: Russian studies report sharper attention and faster learning, linked to its rise in BDNF, the growth factor behind new brain-cell connections. N-Acetyl Semax and Adamax keep the same core and are researched for the same outcomes, so their bars sit level with Semax's. Those bars show what they are studied for, not results measured for them.

Calm. Selank is the calming branch: Russian clinical research reports reduced anxiety without sedation, through the brain's GABA and serotonin systems. The Semax branch reports less anxiety and mental fatigue as a secondary finding.

Research record. Semax and Selank each have documented Russian clinical use and a long research-use history. N-Acetyl Semax has laboratory stability data and a research-use following, but no trials of its own. Adamax has no published study, in people or in animals.

The options in detail

The originals

Semax branch · Focus & Cognition

Semax

Established

A fragment of ACTH, a pituitary stress hormone, finished with a stabilizing tail. It holds Russian regulatory approval, has been studied clinically on stroke recovery and cognitive endpoints, and has a well-described mechanism: it raises BDNF, the growth factor behind new brain-cell connections. It is broken down quickly, which is what the analogues set out to change.

Established: Russian clinical use and BDNF mechanism · Short-acting: each dose has a brief working window

Focus, memory, and learning-speed research
Recovery after neurological stress
The Semax-branch option with a clinical record
A reference point for comparing the analogues

Full overview →Shop →

Selank branch · Calm & Mood

Selank

Established

A fragment of tuftsin, a natural immune-system peptide, finished with the same stabilizing tail as Semax. It holds Russian regulatory approval as an anti-anxiety compound and is studied for calm focus: reduced anxiety and overthinking without sedation, through the brain's GABA and serotonin systems. It also raises BDNF, like Semax.

Established: Russian clinical use for anxiety · Secondary: focus and memory

Anxiety and stress-resilience research
Calm focus without sedation
Mood steadiness under pressure
Researchers who want calm rather than drive

Full overview →Shop →

Semax analogues

Semax branch · Longer-Acting

N-Acetyl Semax

Experimental

Semax with an acetyl group added to its front end, which protects it from the enzymes that break Semax down and gives each dose a longer working window. It is researched for the same focus and clarity outcomes, but no human trial has been run on it: the clinical record belongs to Semax.

Characterized: Semax's BDNF pathway, kept intact · Unstudied in people: its own outcomes

Semax's focus research with a longer window per dose
Sustained attention under heavy cognitive load
Comparing an analogue against its parent
Researchers who accept a thinner evidence base for duration

Full overview →Shop →

Semax branch · Newest Design

Adamax

Experimental

Semax with the same acetyl group plus an adamantane group, a compact ring structure borrowed from P021, a peptide from Alzheimer's disease research, meant to make it more stable and help it reach the brain. No study of Adamax itself has been published, so its potency, duration, and tolerability are unmeasured.

Inferred: mechanism, from Semax's design · Unpublished: every outcome

Early-stage research on the Semax branch's newest design
Comparing the adamantane design against N-Acetyl Semax
Researchers who accept an unmeasured profile
Following a compound from its first research reports

Full overview →Shop →

NASAL OR SUBQ

Nasal spray or subQ injection?

All four come as the same 10 mg vial, and each can be prepared as a nasal spray or drawn into a syringe for a subcutaneous (subQ) injection. The two routes reach the brain differently, and the research behind them is not equal.

	Nasal spray	SubQ injection
How it reaches the brain	Partly direct. Some of each spray travels along the nerves inside the nose straight into the brain; the rest is absorbed into the blood.	Through the blood. All of it enters the bloodstream first and must then cross the blood-brain barrier. These are short peptides that blood enzymes break down quickly.
Research behind it	The clinical route. Semax and Selank are approved in Russia as nasal drops, and their human research used the nose. In animal studies, nasal Semax reaches the brain within minutes.	Mostly animal research. Many animal studies inject these peptides and still report effects in the brain, but the human research was not done this way.
How exact each amount is	Varies. Spray technique, a stuffy nose, or drip down the throat changes how much is absorbed.	Exact. An insulin syringe measures every amount to the unit, and the whole amount goes in every time.
What you need	A glass nasal sprayer (0.1 mL per spray) and BAC water. Mixed once, then sprayed for the life of the bottle. Nasal Preparation Guide →	BAC water and insulin syringes, a fresh syringe each time. Reconstitution Guide →
Commonly reported	Mild nasal irritation now and then.	Redness or a small bump where it goes in.
Suits research that needs	To match the published human research, no needles, and the most direct path to the brain.	The same exact amount every time, including when a stuffy nose would make sprays unreliable.

Same vial, either way

Compound	Research amount	Nasal spray	SubQ injection
Semax	400 mcga vial lasts ~25 days	2 sprays200 mcg per spray	8 units50 mcg per unit
N-Acetyl Semax	400 mcga vial lasts ~25 days	2 sprays200 mcg per spray	8 units50 mcg per unit
Adamax	400 mcga vial lasts ~25 days	2 sprays200 mcg per spray	8 units50 mcg per unit
Selank	500 mcga vial lasts ~20 days	2 sprays250 mcg per spray	10 units50 mcg per unit

How the math works. For subQ, the 10 mg vial is mixed with 2 mL of BAC water, so each unit on an insulin syringe holds 50 mcg (the research reference). For nasal use, the same vial is made up to 5 mL in a sprayer, so each 0.1 mL spray holds 200 mcg; Selank is made up to 4 mL instead, so 2 sprays give its 500 mcg. Either way a vial covers the same number of days. These are preparation figures, not a dosing recommendation.

The analogues. No study has tested either route for N-Acetyl Semax or Adamax, so they are prepared the same way as Semax. Adamax's adamantane group is meant to help it reach the brain from the blood, but that has not been measured by either route.

How to read this comparison

Ratings reflect each option's studied research emphasis relative to the others—not measured effect sizes, head-to-head trial rankings, or a promise of results. The analogues' focus ratings describe what they are researched for, not outcomes measured for them. All of them are offered strictly for laboratory and research use. See each compound page for its full Evidence Snapshot and research findings.