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Summary sheet: Ethylphenidate
Chemical Nomenclature
Common names Ethylphenidate, EPH
Substitutive name Ethylphenidate
Systematic name Ethyl 2-phenyl-2-(piperidin-2-yl)acetate
Class Membership
Psychoactive class Stimulant
Chemical class Phenidate
Routes of Administration

WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.

Threshold 10 mg
Light 20 - 40 mg
Common 40 - 80 mg
Strong 80 - 120 mg
Heavy 120 mg +
Total 4 - 7 hours
Onset 40 - 120 minutes

Threshold < 5 mg
Light 5 - 15 mg
Common 15 - 30 mg
Strong 30 - 50 mg
Heavy 50 mg+
Total 2 - 6 hours
Onset 5 - 20 minutes

DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.


Ethylphenidate (also known as EPH) is a novel stimulant substance of the phenidate class that produces traditional stimulant effects when administered.

It is a closely related analog of methylphenidate (brand names Ritalin, Concerta). The two substances have very similar pharmacological mechanisms but discernible differences in their subjective effects with ethylphenidate often considered to be recreational.

Ethylphenidate is most commonly distributed as a research chemical by online vendors, due to its grey-area legal status in certain countries.


Ethylphenidate is a synthetic molecule of the substituted phenethylamine and substituted phenidate classes. It contains a phenethylamine core featuring a phenyl ring bound to an amino -NH2 group through an ethyl chain. It is structurally similar to amphetamine, featuring a substitution at Rα which is incorporated into a piperidine ring ending at the terminal amine of the phenethylamine chain. Additionally, it contains an ethyl acetate bound to Rβ or its structure. Ethylphenidate is structurally differed to methylphenidate by elongation of the carbon chain. Ethyl- regards the side chain of two carbon atoms, phen- indicates the phenyl ring, id- is contracted from a piperidine ring, and -ate indicates the acetate group containing the oxygens. Ethylphenidate is a chiral compound, presumably produced as a racemic mixture.


Ethylphenidate acts as both a dopamine reuptake inhibitor and norepinephrine reuptake inhibitor, meaning it effectively boosts the levels of the norepinephrine and dopamine neurotransmitters in the brain by binding to and partially blocking the transporter proteins that normally remove those monoamines from the synaptic cleft. This allows dopamine and norepinephrine to accumulate within the brain, resulting in stimulating and euphoric effects.

All available data on ethylphenidate's pharmacokinetics are drawn from studies conducted on rodents. It has been found that ethylphenidate is more selective to the dopamine transporter (DAT) than methylphenidate, having approximately the same efficacy as the parent compound,[1] but with significantly less activity on the norepinephrine transporter (NET).[2] Its dopaminergic pharmacodynamic profile is nearly identical to methylphenidate and is primarily responsible for its euphoric and reinforcing effects.[2]

The following is ethylphenidate's binding profile in the mouse, alongside methylphenidate's. Figures for both the racemic and the dextrorotary enantiomers are given:[3]

Compound Binding DAT Binding NET Uptake DA Uptake NE
d-methylphenidate 139 408 28 46
d-ethylphenidate 276 2479 24 247
dl-methylphenidate 105 1560 24 31
dl-ethylphenidate 382 4824 82 408

Ethylphenidate can be formed within the body (in the liver), when alcohol and methylphenidate are co-ingested.[4] This is most common when large quantities of methylphenidate and alcohol are consumed at the same time, such as in non-medical use or overdose scenarios.[5] A similar process is also known to occur when cocaine and alcohol are consumed together, forming cocaethylene.[6] However, only a few percent of the consumed methylphenidate is converted to ethylphenidate, so a pharmacologically significant dose with measurable physiological effects would never be produced.[4][2]

Subjective effects

The general headspace of ethylphenidate is described by many as one of extreme mental stimulation, increased focus, and powerful euphoria. It contains a large number of typical stimulant cognitive effects. Although negative side effects are usually mild at low to moderate dosages, they become increasingly likely to manifest themselves with higher amounts or extended usage. This particularly holds true during the offset of the experience.

Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), an open research literature based on anecdotal user reports and the personal analyses of PsychonautWiki contributors. As a result, they should be viewed with a healthy degree of skepticism.

It is also worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become increasingly likely with higher doses and may include addiction, severe injury, or death ☠.

Physical effects

Cognitive effects

After effects
Aftereffects (3).svg

Experience reports

There are currently anecdotal reports which describe the effects of this compound within our experience index.

Additional experience reports can be found here:

EthylPhenidate Powder Bag.jpg

Toxicity and harm potential

The toxicity and long-term health effects of recreational ethylphenidate use do not seem to have been studied in any scientific context and the exact toxic dosage is unknown. This is because ethylphenidate has a very limited history of human usage.

Anecdotal evidence from people who have tried ethylphenidate within the community suggests that there do not seem to be any negative health effects attributed to simply trying this substance at low to moderate doses by itself and using it sparingly (but nothing can be completely guaranteed).

It is worth noting that ethylphenidate crystals are particularly abrasive and somewhat caustic to mucous membranes. Careless use will deteriorate the chosen routes of administration so it is important to practice routine maintenance such as soaking the sinus cavity with water prior to and following insufflation.

It will also irritate lung tissue if inhaled, resulting in the production of phlegm and an irritated cough.

It is strongly recommended that one use harm reduction practices when using this substance.

Tolerance and addiction potential

As with other stimulants, the chronic use of ethylphenidate can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal effects may occur if a person suddenly stops their usage.

Tolerance to many of the effects of ethylphenidate develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). ethylphenidate presents cross-tolerance with all dopaminergic stimulants, meaning that after the consumption of ethylphenidate all stimulants will have a reduced effect.


Main article: Stimulant psychosis

Abuse of compounds within the stimulant class at high dosages for prolonged periods of time can potentially result in a stimulant psychosis that may present with a variety of symptoms (e.g., paranoia, hallucinations, or delusions).[7] A review on treatment for amphetamine, dextroamphetamine, and methamphetamine abuse-induced psychosis states that about 5–15% of users fail to recover completely.[7][8] The same review asserts that, based upon at least one trial, antipsychotic medications effectively resolve the symptoms of acute amphetamine psychosis.[7]

Dangerous interactions

Warning: Many psychoactive substances that are reasonably safe to use on their own can suddenly become dangerous and even life-threatening when combined with certain other substances. The following list provides some known dangerous interactions (although it is not guaranteed to include all of them).

Always conduct independent research (e.g. Google, DuckDuckGo, PubMed) to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.

  • 25x-NBOMe & 25x-NBOH - 25x compounds are highly stimulating and physically straining. Combinations with Ethylphenidate should be strictly avoided due to the risk of excessive stimulation and heart strain. This can result in increased blood pressure, vasoconstriction, panic attacks, thought loops, seizures, and heart failure in extreme cases.
  • Alcohol - Combining alcohol with stimulants can be dangerous due to the risk of accidental over-intoxication. Stimulants mask alcohol's depressant effects, which is what most people use to assess their degree of intoxication. Once the stimulant wears off, the depressant effects will be left unopposed, which can result in blackouts and severe respiratory depression. If mixing, the user should strictly limit themselves to only drinking a certain amount of alcohol per hour.
  • DXM - Combinations with DXM should be avoided due to its inhibiting effects on serotonin and norepinephrine reuptake. There is an increased risk of panic attacks and hypertensive crisis, or serotonin syndrome with serotonin releasers (MDMA, methylone, mephedrone, etc.). Monitor blood pressure carefully and avoid strenuous physical activity.
  • MDMA - Any neurotoxic effects of MDMA are likely to be increased when other stimulants are present. There is also a risk of excessive blood pressure and heart strain (cardiotoxicity).
  • MXE - Some reports suggest combinations with MXE may dangerously increase blood pressure and increase the risk of mania and psychosis.
  • Dissociatives - Both classes carry a risk of delusions, mania and psychosis, and these risk may be multiplied when combined.
  • Stimulants - Ethylphenidate may be dangerous to combine with other stimulants like cocaine as they can increase one's heart rate and blood pressure to dangerous levels.
  • Tramadol - Tramadol is known to lower the seizure threshold[9] and combinations with stimulants may further increase this risk.
  • MAOIs - This combination may increase the amount of neurotransmitters such as dopamine to dangerous or even fatal levels. Examples include syrian rue, banisteriopsis caapi, and some antidepressants.[10]
  • MDMA - The neurotoxic effects of MDMA may be increased when combined with other stimulants.
  • Cocaine - This combination may increase strain on the heart.

Legal status

Ethylphenidate is not controlled internationally and remains easily accessible through online research chemical vendors. It is, however, illegal or at least potentially illegal within certain jurisdictions, each of which are listed below:

  • Australia: Australian state and federal legislation contains provisions that mean that analogues of controlled drugs are also covered by the legislation. Ethylphenidate would be an analogue of methylphenidate under this legislation.
  • Austria: Since January 1, 2012, Ethylphenidate is illegal to possess, produce and sell under the NPSG. (Neue-Psychoaktive-Substanzen-Gesetz Österreich)[citation needed]
  • Canada: Ethylphenidate is listed on the CDSA in Schedule III as of May 5, 2017.[11]
  • Denmark: Ethylphenidate is illegal in Denmark as of 1 February 2013.[12]
  • Germany: Ethylphenidate is controlled under Anlage II BtMG (Narcotics Act, Schedule II)[13] as of July 17, 2013.[14] It is illegal to manufacture, possess, import, export, buy, sell, procure or dispense it without a license.[15]
  • Jersey: Ethylphenidate is illegal under the Misuse of Drugs (Jersey) Law 1978.[16]
  • The Netherlands: Ethylphenidate is listed in the Opiumwet (Opium Act)) on Lijst I as of April 27, 2018.[17]
  • Sweden: Ethylphenidate is illegal as of 15 December 2012.[18]
  • Switzerland: Ethylphenidate is a controlled substance specifically named under Verzeichnis D.[19]
  • United Kingdom: Ethylphenidate is a class B drug in the UK as of 31st May 2017 and is illegal to possess, produce or supply.[20]
  • United States: Ethylphenidate is not explicitly controlled in the US, but it could possibly be considered an analog of a Schedule II substance (methylphenidate) under the Federal Analog Act.[citation needed]

See also

External links


  1. Patrick, K. S., Williard, R. L., VanWert, A. L., Dowd, J. J., Oatis, J. E., Middaugh, L. D. (21 April 2005). "Synthesis and pharmacology of ethylphenidate enantiomers: the human transesterification metabolite of methylphenidate and ethanol". Journal of Medicinal Chemistry. 48 (8): 2876–2881. doi:10.1021/jm0490989. ISSN 0022-2623. 
  2. 2.0 2.1 2.2 Williard, R. L., Middaugh, L. D., Zhu, H.-J. B., Patrick, K. S. (February 2007). "Methylphenidate and its ethanol transesterification metabolite ethylphenidate: brain disposition, monoamine transporters and motor activity". Behavioural Pharmacology. 18 (1): 39–51. doi:10.1097/FBP.0b013e3280143226. ISSN 0955-8810. 
  3. Williard, R. L., Middaugh, L. D., Zhu, H.-J. B., Patrick, K. S. (February 2007). "Methylphenidate and its ethanol transesterification metabolite ethylphenidate: brain disposition, monoamine transporters and motor activity". Behavioural Pharmacology. 18 (1): 39–51. doi:10.1097/FBP.0b013e3280143226. ISSN 0955-8810. 
  4. 4.0 4.1 Markowitz, J. S., DeVane, C. L., Boulton, D. W., Nahas, Z., Risch, S. C., Diamond, F., Patrick, K. S. (June 2000). "Ethylphenidate formation in human subjects after the administration of a single dose of methylphenidate and ethanol". Drug Metabolism and Disposition: The Biological Fate of Chemicals. 28 (6): 620–624. ISSN 0090-9556. 
  5. Markowitz, J. S., Logan, B. K., Diamond, F., Patrick, K. S. (August 1999). "Detection of the novel metabolite ethylphenidate after methylphenidate overdose with alcohol coingestion". Journal of Clinical Psychopharmacology. 19 (4): 362–366. doi:10.1097/00004714-199908000-00013. ISSN 0271-0749. 
  6. Bourland, J. A., Martin, D. K., Mayersohn, M. (December 1997). "Carboxylesterase-mediated transesterification of meperidine (Demerol) and methylphenidate (Ritalin) in the presence of [2H6]ethanol: preliminary in vitro findings using a rat liver preparation". Journal of Pharmaceutical Sciences. 86 (12): 1494–1496. doi:10.1021/js970072x. ISSN 0022-3549. 
  7. 7.0 7.1 7.2 Shoptaw, S. J., Kao, U., Ling, W. (21 January 2009). Cochrane Drugs and Alcohol Group, ed. "Treatment for amphetamine psychosis". Cochrane Database of Systematic Reviews. doi:10.1002/14651858.CD003026.pub3. ISSN 1465-1858. 
  8. Hofmann, F. G. (1983). A handbook on drug and alcohol abuse: the biomedical aspects (2nd ed ed.). Oxford University Press. ISBN 9780195030563. 
  9. Talaie, H.; Panahandeh, R.; Fayaznouri, M. R.; Asadi, Z.; Abdollahi, M. (2009). "Dose-independent occurrence of seizure with tramadol". Journal of Medical Toxicology. 5 (2): 63–67. doi:10.1007/BF03161089. eISSN 1937-6995. ISSN 1556-9039. OCLC 163567183. 
  10. Gillman, P. K. (2005). "Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity". British Journal of Anaesthesia. 95 (4): 434–441. doi:10.1093/bja/aei210Freely accessible. eISSN 1471-6771. ISSN 0007-0912. OCLC 01537271. PMID 16051647. 
  11. "Order Amending Schedule III to the Controlled Drugs and Substances Act (Methylphenidate)". Public Works and Government Services Canada. Archived from the original on June 13, 2017. Retrieved December 24, 2019. 
  13. "Anlage II BtMG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 23, 2019. 
  14. "Siebenundzwanzigste Verordnung zur Änderung betäubungsmittelrechtlicher Vorschriften" (in German). Bundesanzeiger Verlag. Retrieved December 23, 2019. 
  15. "§ 29 BtMG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 23, 2019. 
  17. "Opiumwet" (in Dutch). Ministerie van Binnenlandse Zaken en Koninkrijksrelaties. Retrieved August 22, 2021. 
  19. "Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien" (in German). Bundeskanzlei [Federal Chancellery of Switzerland]. Retrieved January 1, 2020. 
  20. The Misuse of Drugs Act 1971 (Amendment) Order 2017