Peptide

Semax

Also known as

Met-Glu-His-Phe-Pro-Gly-Pro · MEHFPGP · H-MEHFPGP-OH · ACTH(4-7)-PGP · (Pro8,Gly9,Pro10)ACTH-(4-10) · ACTH(4-10) analog (heptapeptide shorthand) · Semax 0.1% · Semax 1% · Semax-Hept (1% product talk) · SEMAX® (Russian pharmacy brand discussions) · Семакс · N-Acetyl Semax (related analog — not identical) · N-Acetyl Semax Amidate / NASA (related analog — not identical) · CAS 80714-61-0 (primary registry discussions) · MW ~813.93 g/mol (C37H51N9O10S)

Community talk. May contain inaccuracies. Not medical advice. Not a protocol. Not for human or animal use.

What it is

Focus peptide	A synthetic seven-amino-acid peptide discussed for focus, clearer thinking and memory, usually as nasal drops/spray and sometimes SC injections.
Strengths and relatives	0.1% and 1% nasal products differ tenfold. N-Acetyl Semax, NASA and Adamax are different compounds, not interchangeable with plain Semax.

Notes

Semax is a synthetic peptide discussed for focus, clearer thinking and memory, usually through nasal drops or sprays and sometimes injections. Favorable accounts describe staying with work more easily; others feel nothing, become emotionally flat or lose sleep. It is an experimental nootropic discussion, not a proven healthy-person enhancement.

A seven-amino-acid peptide. Semax modifies an ACTH hormone-protein fragment. Russian nasal formulations are discussed as 0.1% and 1%, strengths that differ tenfold. FDA 2026 PCAC briefing: Semax-related bulk drug substances (Official context · Accessed 2026-09-30)

Plain Semax and its relatives differ. N-Acetyl Semax, N-Acetyl Semax Amidate (NASA) and Adamax are related compounds, not interchangeable versions. Nasal drops, metered sprays and subcutaneous injections also create different exposure questions; oral use is not an established community practice.

Source context — FDA 2026 PCAC briefing: Semax-related bulk drug substances: Staff briefing assessment for proposed compounding uses, not healthy-user efficacy evidence, a final committee vote or a current product approval.

What people notice

Work and recall	Some describe less distraction, easier conversation and recall, and sustained work without a stimulant rush.
Sharper but less connected	A two-week reviewer reported better conversation and memory alongside broken sleep and reduced empathy. Productivity and social connection did not improve together.

Notes

Less distraction and easier recall. One injection user described sustained focus while working through a sales list, without a stimulant-like rush. A two-week reviewer described easier conversation, memory and problem-solving, alongside sleep problems and reduced empathy. My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30) · Semax 2 Week Experience (Personal report · Accessed 2026-09-30)

A strong response and no response share the same thread. The injection dose-response poster credited easier speech and work. Other contributors reported nothing; one tried both nasal and subcutaneous routes, but omitted units beside the amounts. Suspected product problems were speculation, not verified contamination. Semax dose response (Community discussion · Accessed 2026-09-30)

Clear speech can coexist with emotional distance. The two-week reviewer felt conversation and recall improved but social connection became harder. “Clean focus” therefore describes only part of that person’s experience. Semax 2 Week Experience (Personal report · Accessed 2026-09-30)

Sleep and emotional changes matter. The two-week reviewer reported broken sleep, emotional blunting, appetite reduction and impulsivity. A nasal reviewer described evening rumination and craving more after running out. Semax 2 Week Experience (Personal report · Accessed 2026-09-30) · My Experience With Semax (3 Weeks of Use) (Personal report · Accessed 2026-09-30)

Source context — My experience with semax an how it’s helped me: Anonymous reports and products unverified. alxkwl gives inconsistent break lengths and no independently stated route. caferacerguy15 replies were edited. No preparation or sourcing text reproduced.

Source context — Semax 2 Week Experience: Anonymous self-reports; identity, concentration, other substances and outcomes unverified. The inspected sample cannot establish prevalence, causality or kinetics.

Source context — Semax dose response: Anonymous self-reports, not controlled outcomes. Planned course is not a completed cycle. A null commenter omits units; numeric amounts not adopted. Product-quality suspicion is unverified.

Source context — My Experience With Semax (3 Weeks of Use): Anonymous exam report involving a self-prepared formulation. Promotional certainty and recommendations not adopted. Formulation and outcomes unverified.

Doses people talk about

Nasal accounts	One reports 300–600 mcg per use, frequency unstated. Another reports 800–1,200 mcg total daily, mostly mornings with an occasional 400 mcg afternoon amount.
Nasal charts	Older charts give 100–300 or 250–600 mcg per use, often 1–2 uses daily, with some saying 300–600 mcg up to three times daily. Pump-based amounts depend on the actual product.
Route unstated	One two-week reviewer reports 400 mcg twice daily, morning and midday; the route should not be guessed.
Injection accounts	One SC account reports 500 mcg per use. Another injection account reports 0.5–1 mg on earlier weekdays and 1.5 mg on day ten. Older daily injection charts span 100–500 mcg to 0.5–1 mg, without nasal equivalence.

Notes

Nasal: 300–600 mcg per use in one account. That contributor used different amounts depending on study demands; frequency was unstated. Another reported 800–1,200 mcg total per day, mostly mornings with an occasional 400 mcg afternoon amount. These are separate reports. My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30) · Questions About Semax Concentrations, Dosage, Effects, and Supplier Experience (Personal report · Accessed 2026-09-30)

Older nasal bands: 100–300 or 250–600 mcg per use. The preserved forum/guide synthesis describes 1–2 uses daily, with some charts saying 300–600 mcg up to three times daily. Wider 250–1,000 mcg-per-use and 300–1,500+ mcg daily-total claims are not one validated range.

Commercial nasal charts use different schedules. Preserved examples include 250–500 mcg once or twice daily; 500–1,000 mcg once before a demanding task; and 600–900 mcg daily assuming 300 mcg per pump. Those device assumptions are product-specific, not measured output for every spray.

Another account: 400 mcg twice daily, route unstated. The two-week reviewer describes morning and midday use but does not name the route. The reported amount and favorable experience do not establish a target for others. Semax 2 Week Experience (Personal report · Accessed 2026-09-30)

Injection: 500 mcg per use; a separate 1.5 mg report. The first account says subcutaneous and usually alone. The second describes 0.5–1 mg on earlier weekdays and 1.5 mg on day ten. Its enthusiastic response does not establish that increasing the amount works better. My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30) · Semax dose response (Community discussion · Accessed 2026-09-30)

Older injection charts span 100–500 mcg/day to 0.5–1 mg/day. Other preserved examples give 300–600 mcg once daily, 400 mcg/day four days weekly, or 0.5 mg then 0.8 mg daily. These commercial/clinic chart practices cannot supply nasal-to-injection equivalents.

Source context — Questions About Semax Concentrations, Dosage, Effects, and Supplier Experience / Semax 2 Week Experience: Anonymous self-reports; identity, concentration, other substances and outcomes unverified. The inspected sample cannot establish prevalence, causality or kinetics.

Half-life, onset & duration

Felt onset	Nasal reports suggest roughly 10–40 minutes. One injection work account says about an hour; others noticed more after a week.
Felt duration	Older nasal reports describe 2–4 hours or wider 1–6-hour work windows. Separate injection accounts describe all day or about 24 hours; none measures blood clearance.
Half-life	No measured human clearance value is established. The 20-hour forum claim, 15–20-minute lore and secondary 2–5-minute animal estimate have different, unverified origins.

Notes

Nasal reports: roughly 10–40 minutes, sometimes no change. The preserved discussion includes 10–30 and 20–40-minute subjective windows, with 20–60 minutes used to judge a response. One opened spray account remained unchanged after over an hour. Nasal sting itself is not evidence of a cognitive effect. Semax Spray Dosage Question (Personal report · Accessed 2026-09-30)

Injection: about an hour in one work account. The user described settling into focus. Reviewers separately noticed more after a week. Older pre-task charts say 30–45 or 60–90 minutes beforehand; those lead times are not measured onset. My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30) · Semax 2 Week Experience (Personal report · Accessed 2026-09-30)

Nasal focus: 2–4 hours in older reports. Other preserved accounts describe a 1–6-hour work window. Claims of 20–24-hour downstream activity refer to proposed effects, not blood levels. Sleep disruption can remain after the obvious alert feeling fades.

Injection accounts: all day or about 24 hours. One contributor described all-day benefit; another described roughly 24 hours with a peak around two hours and weaker later uses. These individual timelines do not establish a predictable injection duration. Semax dose response (Community discussion · Accessed 2026-09-30) · My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30)

“20 hours” is an uncited forum claim. A LongeCity contributor repeated that number while considering twice-daily use. It conflicts with short-clearance lore and may confuse effect duration with clearance; the post provides no measurement or primary origin. Semax experiences? (Community discussion · Accessed 2026-09-30)

15–20 minutes and 2–5 minutes have different origins. The older record preserves a 15–20-minute plasma claim from community writeups and a 2–5-minute estimate from secondary animal-PK summaries. Neither establishes human clearance. The rat study’s two-minute sampling time is not an elimination half-life.

Human clearance and injection safety remain poorly characterized. FDA found no human pharmacokinetic studies or subcutaneous safety data, and raised impurity, aggregation and immune-response concerns. Committee discussion does not equal approval. FDA 2026 PCAC briefing: Semax-related bulk drug substances (Official context · Accessed 2026-09-30)

Source context — Semax Spray Dosage Question: Anonymous self-reports; identity, concentration, other substances and outcomes unverified. The inspected sample cannot establish prevalence, causality or kinetics. Opening volume wording is internally inconsistent; nominal pump amount is not verified.

Source context — Semax experiences?: Older anonymous forum reports with medication co-use and vendor endorsements. Uncited half-life repetition is not measured kinetics; no prevalence or route comparison established.

Cycles people discuss

Short nasal courses	5–14-day blocks, two weeks on/two off, 14 on/7 off and five weekdays on/two off appear as habits, not proven reset schedules.
Longer charts	Some nasal charts extend to 30 or 60 days; injection charts give 4–8 weeks, sometimes 12. Planned courses and inconsistent break reports do not establish an optimum or protective rest period.

Notes

Short nasal blocks: 5–14 days. Preserved patterns include 7–14 days on followed by equal or longer breaks, two weeks on/two off, 14 on/7 off and five weekdays on/two off. These are habits, not demonstrated receptor-reset schedules.

Longer chart courses: 30 or 60 days. Preserved nasal charts give up to 30 days, or 600 mcg/day up to 60 days, with roughly equal breaks. Injection charts give 4–8 weeks, sometimes 12; one pairs 400 mcg/day four days weekly with four weeks on/four off.

Actual plans differ from completed cycles. The 1.5 mg injection poster planned four weeks on/two off, using weekdays. Another commenter described eight-week courses with eight-week breaks, later saying one-month gaps; their route was not independently stated. Neither supplies a settled cycle rule. Semax dose response (Community discussion · Accessed 2026-09-30) · My experience with semax an how it’s helped me (Community discussion · Accessed 2026-09-30)

Rest is often precautionary. Older discussions describe 10–20-day courses, days-to-weeks off, and eight-week injection charts using five days on/two off then multi-month rest. Tapers are generally not claimed necessary. Safety, tolerance and permanent benefit remain unresolved; breaks do not guarantee protection.

Stacks

Focus and calm combinations	Selank, caffeine/L-theanine, Noopept, racetams, Dihexa and P21 appear in saved stacks. Same-course Semax/Selank use is reported, without established interaction safety.
Prescription stimulants	One LongeCity user described anxiety with 500 mcg plus Ritalin. More stimulation did not establish more useful focus.

Notes

Stacks make credit difficult to assign. A LongeCity user described anxiety with 500 mcg plus Ritalin. Preserved combinations include Selank, caffeine, Noopept, racetams, Dihexa and P21; some people experiment alone because multi-agent experiences cannot isolate Semax or establish interaction safety. Semax experiences? (Community discussion · Accessed 2026-09-30)

+ Selank (classic “focus + calm” pair): Semax for activating focus, Selank for anxiety/calm — often same course; some dose Semax AM and Selank midday/PM; some combine both in one nasal bottle (no published interaction data; targets framed as non-identical). [community]

+ Caffeine / L-theanine: Very common layer; watch overstimulation, especially with higher Semax or NASA. [community]

Overstimulation stacks: Semax + strong stimulants or high NASA doses can feel wired without productive focus. [community]

Watch for

Sleep, mood and nose	Reports include broken sleep, emotional blunting, appetite loss, impulsivity, headache, anxiety and nasal burning/dryness. One estimated first nasal amount around 1 mg preceded panic, nausea and a pounding heart.
Hair changes	Shedding reports include regrowth, lasting thinning and no shedding. The cause and proposed BDNF explanation remain unproven.
Identity and safety	Unknown pump output, tenfold concentration differences and mixed products can change exposure. FDA's saved assessment flags missing human PK/SC safety data and impurity, aggregation and immune-response concerns.

Notes

Nasal irritation, headache and restlessness. Preserved reports include burning, dryness, congestion, drip, metallic taste, fatigue, anxiety and rare visual changes of uncertain cause. Morning/early-afternoon timing or cutoffs around 2–4 PM are reported habits; earlier use does not guarantee sleep.

The favorable ending followed a frightening first reaction. Ace Silver estimated a first nasal amount at about 1 mg and described panic, nausea and a pounding heart within roughly ten minutes. Later clarity coexisted with emotional distance and poor appetite before easing that evening. Spray arithmetic was inconsistent, and several other measures followed the reaction. The whole timeline matters more than the enthusiastic title; it does not identify a safe threshold. First time experience with 0.1% Semax. Bad experience, but then awesome. (Personal report · Accessed 2026-10-09)

Hair shedding reports disagree. One poster attributed thinning to 400 mcg/day of Semax acetate over 13 days, without stating a route. Replies include regrowth, lasting thinning and no shedding. Other causes and hair treatments complicate attribution; the proposed BDNF explanation is unproven. Semax hair loss experiences? (Community discussion · Accessed 2026-09-30)

Concentration and identity errors change the comparison. A 0.1% bottle is not a 1% bottle, and pump counts do not establish micrograms without known output. Pharmacy drops, research powders and mixed Semax/Selank products are different formulations; identity, contamination and degradation remain concerns.

Source context — First time experience with 0.1% Semax. Bad experience, but then awesome.: Approximate self-reported amount, inconsistent spray arithmetic, unverified contents and multiple subsequent calming measures. One account, not a toxicity threshold.

Source context — Semax hair loss experiences?: Anonymous self-reports; identity, concentration, other substances and outcomes unverified. The inspected sample cannot establish prevalence, causality or kinetics. OP certainty is not causal proof. Hair treatments and stress/confounders appear. Route and often chemical form absent.

Full notes

What Semax is

A seven-amino-acid peptide. Semax modifies an ACTH hormone-protein fragment. Russian nasal formulations are discussed as 0.1% and 1%, strengths that differ tenfold. Official context Community
Plain Semax and its relatives differ. N-Acetyl Semax, N-Acetyl Semax Amidate (NASA) and Adamax are related compounds, not interchangeable versions. Nasal drops, metered sprays and subcutaneous injections also create different exposure questions; oral use is not an established community practice. Community Community

What people hope to gain

Less distraction and easier recall. One injection user described sustained focus while working through a sales list, without a stimulant-like rush. A two-week reviewer described easier conversation, memory and problem-solving, alongside sleep problems and reduced empathy. Reddit r/Nootropics Personal report
Feeling sharper can have a cost. The appeal includes brain-fog relief, study stamina and a steadier mood. Yet an alert or intensely analytical feeling can coexist with anxiety, emotional distance or poor sleep; reported productivity does not establish improved intelligence. Community Personal report Personal report

Doses people discuss

Nasal: 300–600 mcg per use in one account. That contributor used different amounts depending on study demands; frequency was unstated. Another reported 800–1,200 mcg total per day, mostly mornings with an occasional 400 mcg afternoon amount. These are separate reports. Reddit r/Nootropics Personal report
Another account: 400 mcg twice daily, route unstated. The two-week reviewer describes morning and midday use but does not name the route. The reported amount and favorable experience do not establish a target for others. Personal report
Older nasal bands: 100–300 or 250–600 mcg per use. The preserved forum/guide synthesis describes 1–2 uses daily, with some charts saying 300–600 mcg up to three times daily. Wider 250–1,000 mcg-per-use and 300–1,500+ mcg daily-total claims are not one validated range. Community
Commercial nasal charts use different schedules. Preserved examples include 250–500 mcg once or twice daily; 500–1,000 mcg once before a demanding task; and 600–900 mcg daily assuming 300 mcg per pump. Those device assumptions are product-specific, not measured output for every spray. Community
Injection: 500 mcg per use; a separate 1.5 mg report. The first account says subcutaneous and usually alone. The second describes 0.5–1 mg on earlier weekdays and 1.5 mg on day ten. Its enthusiastic response does not establish that increasing the amount works better. Reddit r/Nootropics Reddit r/NooTopics
Older injection charts span 100–500 mcg/day to 0.5–1 mg/day. Other preserved examples give 300–600 mcg once daily, 400 mcg/day four days weekly, or 0.5 mg then 0.8 mg daily. These commercial/clinic chart practices cannot supply nasal-to-injection equivalents. Community
Analog amounts and spray counts need their own identity. Preserved NASA discussions mention 200–400 mcg versus plain-Semax 300–600 mcg bands. That does not prove mass equivalence. A spray user reporting a nominal 250 mcg noticed no change after over an hour; the pump output was unverified. Community Personal report

Half-life claims in discussion

“20 hours” is an uncited forum claim. A LongeCity contributor repeated that number while considering twice-daily use. It conflicts with short-clearance lore and may confuse effect duration with clearance; the post provides no measurement or primary origin. LongeCity
15–20 minutes and 2–5 minutes have different origins. The older record preserves a 15–20-minute plasma claim from community writeups and a 2–5-minute estimate from secondary animal-PK summaries. Neither establishes human clearance. The rat study’s two-minute sampling time is not an elimination half-life. Community
A felt effect is a separate clock. Theories involving neurotrophic signaling and the PGP breakdown fragment are used to explain lingering effects. They do not turn a focus window into a measured human half-life or prove when injection effects end. Community

When people notice a change

Nasal reports: roughly 10–40 minutes, sometimes no change. The preserved discussion includes 10–30 and 20–40-minute subjective windows, with 20–60 minutes used to judge a response. One opened spray account remained unchanged after over an hour. Nasal sting itself is not evidence of a cognitive effect. Community Personal report
Injection: about an hour in one work account. The user described settling into focus. Reviewers separately noticed more after a week. Older pre-task charts say 30–45 or 60–90 minutes beforehand; those lead times are not measured onset. Reddit r/Nootropics Personal report Community

How long people describe feeling it

Nasal focus: 2–4 hours in older reports. Other preserved accounts describe a 1–6-hour work window. Claims of 20–24-hour downstream activity refer to proposed effects, not blood levels. Sleep disruption can remain after the obvious alert feeling fades. Community
Injection accounts: all day or about 24 hours. One contributor described all-day benefit; another described roughly 24 hours with a peak around two hours and weaker later uses. These individual timelines do not establish a predictable injection duration. Reddit r/NooTopics Reddit r/Nootropics
After stopping: days of clarity or a quick fade. The older record includes residual clarity for days, disappearance within 1–2 days, and secondary 1–2-week decline claims. None establishes permanent learning gains or a reliable washout interval. Community

Courses and breaks people describe

Short nasal blocks: 5–14 days. Preserved patterns include 7–14 days on followed by equal or longer breaks, two weeks on/two off, 14 on/7 off and five weekdays on/two off. These are habits, not demonstrated receptor-reset schedules. Community
Longer chart courses: 30 or 60 days. Preserved nasal charts give up to 30 days, or 600 mcg/day up to 60 days, with roughly equal breaks. Injection charts give 4–8 weeks, sometimes 12; one pairs 400 mcg/day four days weekly with four weeks on/four off. Community Community
Actual plans differ from completed cycles. The 1.5 mg injection poster planned four weeks on/two off, using weekdays. Another commenter described eight-week courses with eight-week breaks, later saying one-month gaps; their route was not independently stated. Neither supplies a settled cycle rule. Reddit r/NooTopics Reddit r/Nootropics
Rest is often precautionary. Older discussions describe 10–20-day courses, days-to-weeks off, and eight-week injection charts using five days on/two off then multi-month rest. Tapers are generally not claimed necessary. Safety, tolerance and permanent benefit remain unresolved; breaks do not guarantee protection. Community

Tradeoffs and cautions

Sleep and emotional changes matter. The two-week reviewer reported broken sleep, emotional blunting, appetite reduction and impulsivity. A nasal reviewer described evening rumination and craving more after running out. Personal report Personal report
Nasal irritation, headache and restlessness. Preserved reports include burning, dryness, congestion, drip, metallic taste, fatigue, anxiety and rare visual changes of uncertain cause. Morning/early-afternoon timing or cutoffs around 2–4 PM are reported habits; earlier use does not guarantee sleep. Community Community
Hair shedding reports disagree. One poster attributed thinning to 400 mcg/day of Semax acetate over 13 days, without stating a route. Replies include regrowth, lasting thinning and no shedding. Other causes and hair treatments complicate attribution; the proposed BDNF explanation is unproven. Reddit r/Nootropics
Concentration and identity errors change the comparison. A 0.1% bottle is not a 1% bottle, and pump counts do not establish micrograms without known output. Pharmacy drops, research powders and mixed Semax/Selank products are different formulations; identity, contamination and degradation remain concerns. Community Community

What supporting research can and cannot settle

Human clearance and injection safety remain poorly characterized. FDA found no human pharmacokinetic studies or subcutaneous safety data, and raised impurity, aggregation and immune-response concerns. Committee discussion does not equal approval. Official context
Rat sampling does not prove a two-minute half-life. Rat nasal sampling detected parent peptide and a PGP breakdown fragment. Those results establish neither human timing nor healthy-user benefits. Official context

What the experiences add

Clear speech can coexist with emotional distance. The two-week reviewer felt conversation and recall improved but social connection became harder. “Clean focus” therefore describes only part of that person’s experience. Personal report
A strong response and no response share the same thread. The injection dose-response poster credited easier speech and work. Other contributors reported nothing; one tried both nasal and subcutaneous routes, but omitted units beside the amounts. Suspected product problems were speculation, not verified contamination. Reddit r/NooTopics
Stacks make credit difficult to assign. A LongeCity user described anxiety with 500 mcg plus Ritalin. Preserved combinations include Selank, caffeine, Noopept, racetams, Dihexa and P21; some people experiment alone because multi-agent experiences cannot isolate Semax or establish interaction safety. LongeCity Community
Food and “stronger variants” are debated. Empty-stomach timing occurs in older nasal guides, without establishing a requirement. Claims of 60–70% nasal bioavailability or 30–40% lower analog amounts lack a verified human equivalence here; a nonresponse does not prove a different route or variant is needed. Community
The favorable ending followed a frightening first reaction. Ace Silver estimated a first nasal amount at about 1 mg and described panic, nausea and a pounding heart within roughly ten minutes. Later clarity coexisted with emotional distance and poor appetite before easing that evening. Spray arithmetic was inconsistent, and several other measures followed the reaction. The whole timeline matters more than the enthusiastic title; it does not identify a safe threshold. Personal report