Non-peptide

S-23

Also known as

S23 · S 23 · S-23 · S-23 SARM · S23 SARM · Mastorin (informal / research-chem trade discussion) · Ultrabolic (branded research-chem label discussed in forums) · (S)-N-(4-cyano-3-trifluoromethylphenyl)-3-(3-fluoro-4-chlorophenoxy)-2-hydroxy-2-methylpropanamide · s23

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

What it is

Identity	An unapproved, nonsteroidal SARM, a hormone-active compound discussed for strength and a leaner, harder appearance. Selective androgen-receptor activity does not mean muscle-only effects.
Reported form	The accounts concern swallowed capsules, powder or liquids. Their reported milligrams assume that unverified product labels are accurate.

Notes

S-23 is an unapproved, nonsteroidal SARM discussed for strength and a leaner, harder-looking physique. Favorable accounts describe strong pumps and training drive; unfavorable ones describe hormone suppression, hair shedding, anger and poor sleep. Most detailed accounts involve other drugs, so their results do not isolate S-23.

A hormone-active research compound, not a peptide. SARM means selective androgen receptor modulator: it acts on receptors involved in androgen hormone responses. Selective does not mean limited to muscle or free of hormonal effects. Jones et al.: Preclinical characterization of S-23 for hormonal male contraception (Animal context · Accessed 2026-09-30)

The accounts concern swallowed products. Capsules, powder and liquid preparations appear in discussion. Labeled research products are not approved medicines with verified contents; reported milligrams assume label accuracy. S23 (SARM) has significantly reduced my hairloss (Personal report · Accessed 2026-09-30)

Source context — Jones et al.: Preclinical characterization of S-23 for hormonal male contraception: Animal populations and distinct contraceptive/kinetic experiments. Neither human half-life, self-use dose, contraception nor human recovery is established. PubMed abstract URL itself returned no usable body on this access.

Source context — S23 (SARM) has significantly reduced my hairloss: Unusual single person's self-counted shedding, without controlled assessment or measured hormones; testosterone and planned additional interventions confound interpretation. Quoted copies are not independent reports. The clarification is one account, not corroboration; exact timing of testosterone initiation is not established.

What people notice

Strength and appearance	Accounts describe stronger lifts during a cut, pumps or a drier look, usually with testosterone or other drugs. One early-pump account reported little extra strength.
Results can disappoint	One author felt flatter at 30–40 mg/day. Another realized fat gain was being mistaken for a successful recomp; food, training and other drugs changed too.

Notes

Strength while cutting. One Reddit author reported stronger lifts despite dieting and felt more driven in the gym. This followed eight weeks of RAD-140 and included HCG, a hormone-related drug, throughout; it cannot establish S-23's independent effect. My Experience with S23 (with before and after pictures) (Personal report · Accessed 2026-09-30)

Fuller muscles and a drier look. A bodybuilding blogger relays a friend's eight-week cut with testosterone replacement: strength retention and a drier appearance. This is secondhand experience on a commercially linked site, not measured fat loss. S23 SARM Overview – Preclinical Profile, Results, Reviews & Side Effects (Secondhand community claim · Accessed 2026-09-30)

Pumps by days three or four in one account. The 10 mg/day split-dose commenter described early appearance and pump changes while also on testosterone replacement. Strength did not increase much. That is a repeated-use timeline, not onset after one administration. What's your experience with sarm S23 (Community discussion · Accessed 2026-09-30)

Higher reports are separate outliers. One account tried 30–40 mg/day and felt flatter rather than more vascular. A different commenter claimed 60–100 mg/day for two months. Neither establishes an escalation plan or a safe upper amount. S-23 – Cycle Report (ended early due to sides, READ before you run) (Personal report · Accessed 2026-09-30) · What's your experience with sarm S23 (Community discussion · Accessed 2026-09-30)

Looking leaner is not the same as losing only fat. The early-ended-cycle author gained weight and realized fat gain was being mistaken for recomp. Testosterone, brief Anadrol use, more food and renewed leg training complicated the account. S-23 – Cycle Report (ended early due to sides, READ before you run) (Personal report · Accessed 2026-09-30)

Source context — My Experience with S23 (with before and after pictures): One author and follow-ups, not multiple independent accounts. Promotes own blog. Unverified product, self-assessed photos and body composition; RAD-140 then S-23, HCG and later hormone-drug treatment confound outcomes. Photos themselves were not visually assessed.

Source context — S23 SARM Overview – Preclinical Profile, Results, Reviews & Side Effects: Secondhand friend account, not author self-experiment or clinical study. Commercial/affiliate product links elsewhere on page. Unsupported absolute claims about protection, recovery and hormone replacement are not adopted.

Source context — What's your experience with sarm S23: Different people and incomplete schedules; not one course, survey or dose recommendation. User claim of a lab-tested product was not independently verified. TRT and other agents recur. Strong contraception/toxicity assertions in replies are not clinical measurements.

Source context — S-23 – Cycle Report (ended early due to sides, READ before you run): Deleted identity; cannot establish verified product, measurements or causality. Testosterone and brief Anadrol use, food changes and returning leg training. Decision to end early is qualified by OP's own possible extension, not assumed completed follow-up.

Doses people talk about

10–30 mg oral daily	Separate accounts include 10 mg/day as two 5 mg amounts and 20 mg/day split morning/evening. This is reported exposure, not a validated human dose band.
Other schedules and outliers	25 mg each morning or divided, and a secondhand 30 mg/day as three 10 mg amounts, appear. Separate 30–40 and 60–100 mg/day reports do not establish an escalation plan or safe ceiling.

Notes

Oral daily totals around 10–30 mg. These amounts occur in separate accounts, not a validated human dosing range. One report used 10 mg/day as two 5 mg administrations; another used 20 mg/day split morning and evening. What's your experience with sarm S23 (Community discussion · Accessed 2026-09-30) · My Experience with S23 (with before and after pictures) (Personal report · Accessed 2026-09-30)

Once daily and divided amounts both appear. A timing-thread author took 25 mg each morning; another divided that total. The blogger's example used 30 mg/day as three 10 mg amounts. These are reports, not proven equivalent schedules. Do I split dose on S-23?? (Community discussion · Accessed 2026-09-30) · S23 SARM Overview – Preclinical Profile, Results, Reviews & Side Effects (Secondhand community claim · Accessed 2026-09-30)

Source context — Do I split dose on S-23??: Preferences and repeated number without human measurements. Does not compare schedules or measure one-dose benefit duration. Blanket insomnia statements and proposed mitigations are not adopted as facts.

Half-life, onset & duration

Felt onset	One 10 mg/day split-dose user on testosterone replacement noticed pumps by days three or four. No dependable first-dose clock is established; insomnia became severe around week four in another account.
Felt duration	No measured hours-of-pumps or strength window. One mixed-cycle author felt horrible during the first two weeks of post-cycle drug treatment; that is not S-23 clearance or a universal recovery time.
Half-life	The circulated roughly twelve-hour value comes from rats: oral 11.9 hours, IV 10.9 hours. An unsupported eight-hour forum claim is separate; human half-life remains unknown here.

Notes

No dependable first-dose clock. Early gym reports do not establish minutes-to-effect. In an adverse account, insomnia became bad around week four; unwanted changes can emerge later than the initial feel. S-23 – Cycle Report (ended early due to sides, READ before you run) (Personal report · Accessed 2026-09-30)

One-dose duration is not established. The timing discussion covers daily schedules and sleep concerns, without measuring how many hours strength or pumps last. A split schedule cannot supply that answer. Do I split dose on S-23?? (Community discussion · Accessed 2026-09-30)

After stopping can feel different. The four-week author felt horrible during the first two weeks of post-cycle drug treatment. This recovery experience after a mixed cycle is not S-23's clearance time or a universal withdrawal duration. My Experience with S23 (with before and after pictures) (Personal report · Accessed 2026-09-30)

About 12 hours is circulated; its origin is rats. A split-dose thread repeats 11.9 hours, rounded to twelve. Another user explicitly says the estimate came from rats. This describes animal blood-level decline, not a measured human half-life or a twelve-hour workout effect. Do I split dose on S-23?? (Community discussion · Accessed 2026-09-30) · S23 with Test – Antivenom32's experience (Personal report · Accessed 2026-09-30)

An eight-hour claim also appears. A separate commenter supplies eight hours without supporting measurements. It should remain an unsupported forum claim, not be blended into an 8–12-hour human range. Dependable human timing remains unknown. Why is there such little hype about YK11, S4, and S23? (Community discussion · Accessed 2026-09-30) · S23 with Test – Antivenom32's experience (Personal report · Accessed 2026-09-30)

The contraception reputation comes from animal work. S-23 combined with estradiol benzoate produced reversible infertility in male rats. This establishes neither human contraception nor guaranteed recovery. The rat oral half-life was 11.9 hours; the intravenous value was 10.9 hours. Jones et al.: Preclinical characterization of S-23 for hormonal male contraception (Animal context · Accessed 2026-09-30)

Source context — S23 with Test – Antivenom32's experience: Unverified hormone/product exposure and self-reported labs without records. 'Crashed triglycerides' wording does not establish a particular lipid abnormality. Contraception, receptor competition, drug avoidance and PCT advice elsewhere in thread not adopted as established guidance.

Source context — Why is there such little hype about YK11, S4, and S23?: The eight-hour claim has no measurement or citation. Identity corrections in replies are not evidence of absence of all visual risk. Various participants, unverified products and mixed exposures.

Cycles people discuss

Reported blocks	Accounts describe four weeks after an eight-week RAD-140 cycle or roughly six to eight weeks of S-23. One author planned to stop early because of hair loss; no agreed recovery or repeat interval emerges.

Notes

Four weeks and roughly six to eight weeks appear. A four-week S-23 period followed eight weeks of RAD-140. A different author decided to end a planned eight-week period about two weeks early because of hair loss, while still considering extending it. These are individual histories. My Experience with S23 (with before and after pictures) (Personal report · Accessed 2026-09-30) · S-23 – Cycle Report (ended early due to sides, READ before you run) (Personal report · Accessed 2026-09-30)

No agreed recovery or repeat-cycle interval. PCT means post-cycle therapy, usually discussion of hormone-related drugs after stopping. One user would not repeat S-23 more than yearly because it felt taxing; that opinion does not verify hormone recovery or establish a medically checked break length. S23 with Test – Antivenom32's experience (Personal report · Accessed 2026-09-30)

Stacks

Hormone and other stacks	YK-11, testosterone, HCG, Cardarine, tadalafil and tirzepatide appear across different accounts. These mixtures do not isolate S-23; testosterone or post-cycle drugs do not establish recovered natural hormones or fertility.

Notes

Stacks explain part of the uncertainty. YK-11 combinations and accounts involving testosterone, Cardarine, tadalafil and tirzepatide occur alongside simpler reports. A favorable combination cannot identify which substance caused a change, and absence of symptoms cannot verify the product or long-term safety. What's your experience with sarm S23 (Community discussion · Accessed 2026-09-30)

Suppression means reduced natural hormone production. Sex drive can increase while natural hormone production is suppressed. Testosterone, HCG and other hormone drugs appear in discussion, but feeling well on a stack does not establish recovery, fertility or safe interactions.

Watch for

Hormones, hair and mood	Reports include natural hormone suppression, shedding, anger/irritability, poor sleep and persistent cramps. Increased libido or feeling well on testosterone does not establish hormonal recovery.
Serious class risks	FDA's SARM warnings include liver, cardiovascular, fertility and pregnancy harms. Chest pain, breathing trouble, jaundice or dark urine warrant assessment. Rat infertility research does not establish human contraception or guaranteed recovery.

Notes

Hair, mood, sleep and cramps can outweigh the appeal. Reports include hair shedding, irritability, insomnia and persistent cramping. Others describe few noticeable symptoms. The original lipid concerns and uncertain long-term safety remain relevant even when someone likes the gym effects. S23 experiences (Community discussion · Accessed 2026-09-30) · S23 side effects? (Community discussion · Accessed 2026-09-30)

Unapproved status and serious health risks. FDA identifies SARM products as unapproved drugs, not dietary supplements, and warns about liver, cardiovascular, fertility and pregnancy harms. These are class-level warnings, not a measured S-23 risk rate. Certain bodybuilding products put consumers at risk for heart attack, stroke, serious liver damage and more (Official context · Accessed 2026-09-30)

Concerning symptoms need medical assessment. Chest pain, trouble breathing, jaundice or dark urine warrant medical attention. So do severe allergies, neurological changes or uncontrolled blood pressure or blood sugar. Forum suggestions about water, supplements or PCT do not establish protection. Certain bodybuilding products put consumers at risk for heart attack, stroke, serious liver damage and more (Official context · Accessed 2026-09-30)

Source context — S23 experiences: The 20 mg response lacks frequency, so not converted into a daily total. Independent complaints are distinguished from quoted reposts. Forum has company representative signatures; these specific comments are not a controlled comparison or purity check.

Source context — S23 side effects?: Unverified products, doses, absent labs and subjective outcomes. The OP's dose is unstated and blood-pressure cause not measured. Replies about LGD/S4 remain those identities, not S23 onset or vision evidence.

Source context — Certain bodybuilding products put consumers at risk for heart attack, stroke, serious liver damage and more: Class-level regulatory and safety context, not S23-specific incidence or an interaction trial. No claim that every listed outcome is inevitable.

Full notes

What S-23 is

A hormone-active research compound, not a peptide. SARM means selective androgen receptor modulator: it acts on receptors involved in androgen hormone responses. Selective does not mean limited to muscle or free of hormonal effects. Animal context
The accounts concern swallowed products. Capsules, powder and liquid preparations appear in discussion. Labeled research products are not approved medicines with verified contents; reported milligrams assume label accuracy. Community Personal report
Recomp means changing fat and muscle together. People seek a leaner appearance while maintaining or increasing strength. Scale weight alone cannot show how much muscle or fat changed, especially with altered diet, training and other anabolic drugs. Community

Benefits people seek and report

Strength while cutting. One Reddit author reported stronger lifts despite dieting and felt more driven in the gym. This followed eight weeks of RAD-140 and included HCG, a hormone-related drug, throughout; it cannot establish S-23's independent effect. Personal report
Fuller muscles and a drier look. A bodybuilding blogger relays a friend's eight-week cut with testosterone replacement: strength retention and a drier appearance. This is secondhand experience on a commercially linked site, not measured fat loss. More Plates More Dates

Doses people discuss

Oral daily totals around 10–30 mg. These amounts occur in separate accounts, not a validated human dosing range. One report used 10 mg/day as two 5 mg administrations; another used 20 mg/day split morning and evening. Reddit r/SARMs Personal report Community
Once daily and divided amounts both appear. A timing-thread author took 25 mg each morning; another divided that total. The blogger's example used 30 mg/day as three 10 mg amounts. These are reports, not proven equivalent schedules. Reddit r/sarmssourcetalk More Plates More Dates
Higher reports are separate outliers. One account tried 30–40 mg/day and felt flatter rather than more vascular. A different commenter claimed 60–100 mg/day for two months. Neither establishes an escalation plan or a safe upper amount. Personal report Reddit r/SARMs

Half-life claims in the community

About 12 hours is circulated; its origin is rats. A split-dose thread repeats 11.9 hours, rounded to twelve. Another user explicitly says the estimate came from rats. This describes animal blood-level decline, not a measured human half-life or a twelve-hour workout effect. Reddit r/sarmssourcetalk Personal report
An eight-hour claim also appears. A separate commenter supplies eight hours without supporting measurements. It should remain an unsupported forum claim, not be blended into an 8–12-hour human range. Dependable human timing remains unknown. Reddit r/sarmssourcetalk Personal report

When people first notice changes

Pumps by days three or four in one account. The 10 mg/day split-dose commenter described early appearance and pump changes while also on testosterone replacement. Strength did not increase much. That is a repeated-use timeline, not onset after one administration. Reddit r/SARMs
No dependable first-dose clock. Early gym reports do not establish minutes-to-effect. In an adverse account, insomnia became bad around week four; unwanted changes can emerge later than the initial feel. Community Personal report

How long effects feel noticeable

One-dose duration is not established. The timing discussion covers daily schedules and sleep concerns, without measuring how many hours strength or pumps last. A split schedule cannot supply that answer. Reddit r/sarmssourcetalk
After stopping can feel different. The four-week author felt horrible during the first two weeks of post-cycle drug treatment. This recovery experience after a mixed cycle is not S-23's clearance time or a universal withdrawal duration. Personal report

Courses and breaks people describe

Four weeks and roughly six to eight weeks appear. A four-week S-23 period followed eight weeks of RAD-140. A different author decided to end a planned eight-week period about two weeks early because of hair loss, while still considering extending it. These are individual histories. Personal report Personal report
No agreed recovery or repeat-cycle interval. PCT means post-cycle therapy, usually discussion of hormone-related drugs after stopping. One user would not repeat S-23 more than yearly because it felt taxing; that opinion does not verify hormone recovery or establish a medically checked break length. Personal report Community

Good to know

Suppression means reduced natural hormone production. Sex drive can increase while natural hormone production is suppressed. Testosterone, HCG and other hormone drugs appear in discussion, but feeling well on a stack does not establish recovery, fertility or safe interactions. Community
Hair, mood, sleep and cramps can outweigh the appeal. Reports include hair shedding, irritability, insomnia and persistent cramping. Others describe few noticeable symptoms. The original lipid concerns and uncertain long-term safety remain relevant even when someone likes the gym effects. Community AnabolicMinds Reddit r/sarmssourcetalk
Unapproved status and serious health risks. FDA identifies SARM products as unapproved drugs, not dietary supplements, and warns about liver, cardiovascular, fertility and pregnancy harms. These are class-level warnings, not a measured S-23 risk rate. Official context
Concerning symptoms need medical assessment. Chest pain, trouble breathing, jaundice or dark urine warrant medical attention. So do severe allergies, neurological changes or uncontrolled blood pressure or blood sugar. Forum suggestions about water, supplements or PCT do not establish protection. Official context Community
The contraception reputation comes from animal work. S-23 combined with estradiol benzoate produced reversible infertility in male rats. This establishes neither human contraception nor guaranteed recovery. The rat oral half-life was 11.9 hours; the intravenous value was 10.9 hours. Animal context

What the experiences disagree about

Looking leaner is not the same as losing only fat. The early-ended-cycle author gained weight and realized fat gain was being mistaken for recomp. Testosterone, brief Anadrol use, more food and renewed leg training complicated the account. Personal report
Cramps and thirst changed the experience. On AnabolicMinds, widthbrah described persistent thirst and cramps; Hyde reported cramping despite electrolytes and taurine. Another contributor preferred S-23 to LGD. These opinions cannot establish which compound is better. AnabolicMinds
Hair reports run in opposite directions. A HairLossTalk author reported fewer shed hairs at 20 mg/day with testosterone. In replies, he said he continued S-23 and no longer felt suppressed with testosterone. This contrasts with shedding reports; it does not establish a hair-loss treatment. Personal report Community
Some feel strong; others feel unwell. One questioner described dizziness and feeling mentally absent after taking it; others reported strong gains without noticed symptoms. The questioner supplied no dose or measurements; replies guessing blood pressure cannot diagnose the cause. Reddit r/sarmssourcetalk
Stacks explain part of the uncertainty. YK-11 combinations and accounts involving testosterone, Cardarine, tadalafil and tirzepatide occur alongside simpler reports. A favorable combination cannot identify which substance caused a change, and absence of symptoms cannot verify the product or long-term safety. Reddit r/SARMs Community