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Phenylpiracetam

Also known as Phenotropil, Carphedon, Fonturacetam, 4-phenylpiracetam, Actitropil

Not a peptide but a piracetam derivative; banned in competition, with clinical data almost only from Russia.

early-clinical Neuro & cognition research chemical

At a glance

Category
Neuro & cognition
Status
research chemical
Route
oral (tablets)
Half-life
No independently published human pharmacokinetic study that PeptideX has been able to read. It is sold and studied as a racemate, and the two enantiomers are not pharmacologically equivalent 2, so a single figure would in any case describe a mixture rather than a drug.
Onset
Reported in the Russian asthenia studies as a course effect assessed at 30 days rather than an acute one 1
Molecular weight
218.25 g/mol (C12H14N2O2) 6

Phenylpiracetam is not a peptide. It is a racetam - piracetam with a phenyl group added to the pyrrolidinone ring - included here because it is sold by the same vendors as Semax, Selank and Noopept and searched for in the same context. It was first described in the Soviet literature in 1983 12 and has been registered in Russia and some neighbouring countries as Phenotropil, more recently marketed there as Actitropil. It is not approved by the FDA or the EMA and it is not a lawful dietary supplement ingredient in the United States, though it is repeatedly found in products sold as cognitive-enhancement supplements 3910. It does not appear as an intervention in any study registered on ClinicalTrials.gov: a search of the registry in July 2026 returns zero studies 5. WADA has listed it since the early 2000s under the name carphedon, and it appears on the current list as fonturacetam 4.

Doping status: Prohibited in competition. The 2026 Prohibited List names 'Fonturacetam [4-phenylpiracetam (carphedon)]' in section S6.A, non-specified stimulants; S6 applies in competition only

Checked against the WADA 2026 Prohibited List. For a specific product and country, Global DRO is the lookup athletes are expected to use — the List names substances, not brand names.

This is a short entry. There is little or no published research on this compound, so there is correspondingly little to report. Empty dosing or reconstitution sections mean no credible figures exist — not that they were left out.

Mechanism of action

Phenylpiracetam differs from piracetam by a phenyl substituent, which makes it considerably more lipophilic and, unlike piracetam, gives it stimulant-like activity. The clearest mechanistic account comes from work at the Latvian Institute of Organic Synthesis: the compound is a dopamine transporter inhibitor, and its activity is stereoselective. Both enantiomers increase locomotor activity and produce antidepressant-like effects in rodents, but memory enhancement in a passive avoidance test was a property of the R-enantiomer only, at a dose fifty times lower than the locomotor dose, despite both enantiomers reaching similar brain concentrations 2. A separate line of work reports that the S-enantiomer, a selective DAT inhibitor, reduces body weight gain in rodents without affecting locomotor activity 8.

That stereochemistry matters practically. The material sold, and the material used in the Russian clinical studies, is the racemate - a mixture of an enantiomer with cognitive activity and one without. Descriptions of phenylpiracetam that treat the racemate's effects as a single pharmacology are, strictly, describing two drugs at once. Beyond the dopamine transporter, the broader racetam mechanism remains poorly defined 11; the class has been in use for fifty years without a settled account of how it works.

What the research shows

The clinical literature is almost entirely Russian, published in Russian-language domestic journals, mostly small, mostly uncontrolled, and not registered on any public trial registry 5. It should be described plainly rather than inflated or dismissed: real studies exist, they report specific numbers, and none of them can be verified from outside Russia. Outside that literature there is a body of rodent pharmacology, some of it from Latvia and published in international journals 28, and a Western literature that consists mainly of analytical chemistry - methods for detecting the compound in urine for doping control 7 and surveys finding it in supplements where it does not belong 3910.

Research in humans

The most substantial synthesis is a 2025 systematic review and meta-analysis published in a Russian journal, covering 11 articles and 549 patients with a mean age of 46, all of whom received 200 mg daily 1. It reports that the MFI-20 fatigue score fell by an average of 16.3 points after a one-month course, assessed on day 30, with side effects in 5.5 per cent of patients, transient and resolving within a week of continued treatment. Two things about that result need saying. First, the pooled estimate as reported is a before-and-after change within treated patients, not a difference against placebo - the abstract describes no control comparison, and asthenia is a condition in which before-and-after change is a particularly unreliable measure. Second, all eleven included studies are Russian. Beyond asthenia there is a scattered Russian clinical literature on phenylpiracetam as an add-on in epilepsy, in stroke rehabilitation, in vascular encephalopathy and after mild head injury, published across two decades in the same handful of journals, generally small and generally open-label. PeptideX has read English abstracts of these; it has not been able to read the protocols.

Animal and lab research

The rodent work is more accessible and more informative about mechanism than about benefit. Zvejniece and colleagues (2011) established the stereoselective profile described above and localised memory enhancement to the R-enantiomer 2. Later work characterised S-phenylpiracetam as a selective dopamine transporter inhibitor that reduces body weight gain without a locomotor effect 8, and reported neuroprotective and anti-inflammatory activity for R-phenylpiracetam in mouse inflammation models. The original Soviet characterisation dates from 1983 12.

Caveats. Verifiability is the central problem, and it is the same one that applies to bromantane. The trials are not registered, the full texts are in Russian, the journals are domestic, and the product is domestically registered - a combination in which publication bias cannot be measured. The one meta-analysis is a meta-analysis of that literature, so it inherits its limitations rather than correcting them, and it appears to pool uncontrolled before-after changes. There is no independent Western replication of any clinical finding. Separately, the material sold outside Russia is unreliable in a documented way: Cohen and colleagues (2021) bought ten supplements labelled as containing racetams including phenylpiracetam and found that several declared drugs were absent while three undeclared unapproved drugs were present, and that 75 per cent of stated quantities were inaccurate 3. Reviews of nootropic supplement adulteration reach the same conclusion across a wider sample 910.

What it is used for

  • Registered in Russia and some neighbouring countries for asthenia, and used there as an adjunct in stroke rehabilitation, epilepsy and post-traumatic states 1
  • Sold internationally as a nootropic and stimulant for focus, fatigue and physical performance, alongside the Russian peptides Semax and Selank
  • Found as an undeclared or inaccurately declared ingredient in supplements marketed for cognitive enhancement 3910
  • A doping-control analyte: methods for determining carphedon in human urine have existed since the late 1990s 7

Dosing

Dose
200 mg per day - the daily dose used in every one of the 11 studies pooled by the 2025 Russian meta-analysis
Frequency
usually divided across the day in the Russian literature; the meta-analysis reports only the daily total
Route
oral
Duration
One month, the course length in the pooled studies; no published human study of continuous use beyond it has been found
  • The 200 mg daily figure and the one-month course are what the 2025 Russian meta-analysis reports as common to all 11 pooled studies 1. They are descriptive of what was given in clinical studies of a domestically registered tablet. This is not advice, and no Western regulator has evaluated it.
  • It is also, notably, lower than the doses that circulate online, where 300 to 600 mg is commonly discussed. Those higher figures have no published clinical basis that PeptideX has been able to find.
  • Tolerance is widely reported by users within days of daily dosing, which is consistent with a dopamine transporter mechanism 28 but has not been studied in a published trial. The Russian studies used fixed doses over a fixed month and did not report on it.
  • What is sold is the racemate, and the two enantiomers do different things 2. A milligram figure therefore describes a mixture, and no product on sale specifies its enantiomeric composition.
  • Product identity cannot be assumed. In one analysis of supplements labelled as containing racetams, several declared drugs were not present at all and three-quarters of stated quantities were wrong 3.

These figures describe what the literature and published protocols report. They are not advice and not a dosing instruction.

Protocols

Fonturacetam for asthenia (dose common to all pooled Russian studies)

published trial

Source: Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 2025 - Devlikamova and Safina; systematic review and meta-analysis of 11 studies, 549 patients, all using the same daily dose

30 days200 mg fonturacetam (phenylpiracetam) daily by mouth

This is the schedule common to the entire pooled Russian literature rather than the protocol of one named trial. The pooled outcome - a 16.3 point fall in MFI-20 fatigue score at day 30 - is reported as a within-group change and not as a difference from placebo, so it does not establish an effect over and above the natural course of asthenia and the response to being treated.

Online nootropic use (user-reported)

user protocol — not validated

Source: Nootropic forum reports and vendor labelling

This is not a validated schedule. It is a pattern that circulates among users and sellers, reproduced because it is what people actually follow — not because it has been tested. No trial established these doses, this interval or this duration, and nobody is checking what is in the vial. Treat every number below as an assertion, not a finding.

Commonly reported single dose100-200 mg, taken as needed before a demanding task
Commonly reported daily total300-600 mg, above the 200 mg used in the Russian studies
Reported patternmostly intermittent - 'as needed' or a few days at a time - because tolerance is said to build within days of daily use

The daily totals that circulate online, commonly 300 to 600 mg, are above the 200 mg used in every study the 2025 Russian meta-analysis pooled 1, and have no published clinical basis that could be found. Users overwhelmingly report that the effect fades within a few days of consecutive dosing, which is why intermittent 'as needed' use dominates the reports; this tolerance has never been characterised in a trial. Two things undercut any dose figure here. What is sold is the racemate, a mixture of one enantiomer with cognitive activity and one without 2, so a milligram number describes two drugs at once and no product states its enantiomeric split. And the product may not contain what the label says: in one analysis of supplements labelled as containing racetams, several declared drugs were absent, three undeclared unapproved drugs were present, and 75 per cent of stated quantities were wrong 3.

Schedules are reproduced as their source states them. Units, IU and milligrams explains why the figures are not interchangeable between products.

Reconstitution

An oral tablet in its registered Russian form; sold internationally as loose powder or capsules. Nothing to reconstitute.

Safety

Side effects

  • In the pooled Russian asthenia studies, side effects were reported in 5.5 per cent of patients, described as transient and resolving within a week of continued treatment 1 - a figure drawn from largely uncontrolled studies of a domestically registered product
  • Insomnia if taken late in the day, and overstimulation, consistent with dopamine transporter inhibition 2
  • Irritability, agitation and headache
  • Loss of effect within days of repeated dosing is widely described by users; it has not been characterised in any published trial
  • No systematic safety data outside the Russian literature, and nothing at all on use beyond a one-month course 1
  • A distinct hazard that has nothing to do with the molecule: products sold as containing phenylpiracetam have been found to contain other unapproved drugs instead, at inaccurate quantities 3910

Do not use if

  • Any athlete competing in a sport subject to anti-doping rules - fonturacetam (4-phenylpiracetam, carphedon) is named in section S6.A of the WADA Prohibited List and is prohibited in competition 4
  • Pregnancy and breastfeeding: no adequate human data
  • Children and adolescents: no data
  • Existing psychosis, bipolar disorder or an anxiety disorder that worsens with stimulants - a dopamine transporter inhibitor is a foreseeable risk in these conditions and has not been studied in them
  • Concurrent stimulant or dopaminergic medication, including methylphenidate, amphetamines and MAO inhibitors - the combinations are unstudied

Interactions

Not systematically studied in humans. Dopamine transporter inhibition 28 makes additive effects with methylphenidate, amphetamines, bupropion and MAO inhibitors plausible in principle, and none of those combinations appears in any published study. There is no interaction data for the multi-compound stacks phenylpiracetam is commonly sold into. Where supplements have been found to contain undeclared additional unapproved drugs 3, the practical interaction risk is with substances the user does not know they are taking.

Sources