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Summary sheet: Propylhexedrine
Molecular structure of Propylhexedrine
Chemical Nomenclature
Common names Propylhexedrine, Benzedrex
Substitutive name Benzedrex, Obesin
Systematic name 1-cyclohexyl-N-methylpropan-2-amine
Class Membership
Psychoactive class Stimulant
Chemical class Cycloalkylamine
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 - 31.25 mg
Light 31.25 - 62.5 mg
Common 62.5 - 125 mg
Strong 125 - 187.5 mg
Heavy 187.5 mg +
Total 4 - 10 hours
Onset 10 - 30 minutes
Come up 15 - 90 minutes
Peak 2 - 5 hours
Offset 1 - 3 hours
After effects 2 - 12 hours

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.

Propylhexedrine (commonly known as Benzedrex and Obesin) is a synthetic stimulant and structural analog of methamphetamine that is widely used medicinally as a nasal decongestant (for relief of congestion due to colds, allergies and allergic rhinitis) and sometimes used recreationally as an over-the-counter "legal high".

In the United States, Propylhexedrine is most commonly found in over-the-counter Benzedrex inhalers. Benzedrex was first manufactured by Smith, Kline and French after the Benzedrine inhaler, which contained racemic amphetamine, became unavailable following the placement of amphetamines on the US Schedule II status (highest abuse potential, yet with accepted medicinal uses). Propylhexedrine has also seen use in Europe as an appetite suppressant under the trade name Obesin.


Propylhexedrine is structurally similar to phenylethylamine and its derivatives, with the only structural difference being the substitution of an alicyclic cyclohexyl group for the aromatic phenyl group of phenethylamine. It can be considered a structural analog of methamphetamine, with the main difference being that propylhexedrine has a saturated cyclohexane ring where methamphetamine has a benzene ring.

A side by side comparison of these two molecules

Moreover, propylhexedrine is a chiral compound (the α-carbon is chiral), and active ingredient contained in Benzedrex inhalers is racemic (RS)-propylhexedrine as the free base. (S)-Propylhexedrine, also known as levopropylhexedrine, is believed to be the more biologically active isomer of the two. (S)-Propylhexedrine can be synthesized from methamphetamine.


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This pharmacology section is incomplete.

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Propylhexedrine affects the central nervous system (CNS) by acting as a releasing agent for monoamine neurotransmitters such as dopamine, norepinephrine, and serotonin by binding to and reversing their transporters, leading to the release of them into the synaptic cleft. The increased level of monoamines within the synapse is thought to result in increased activity at these receptors. Additionally, propylhexedrine appears to antagonize the VMAT2 transporter, leading to a further increase in the aforementioned monoamines.

The pharmacological actions of propylhexedrine are similar to that of structurally similar stimulant phenethylamines, such as amphetamine or methamphetamine, albeit in a generally less potent and recreationally desirable fashion.

Subjective effects

This subjective effect breakdown is a stub.

As such, it may contain incomplete or wrong information and is still in progress.

You can help by expanding it.

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. The listed effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances and are more likely to induce a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.

Physical effects

Visual effects

Cognitive effects

After effects
Aftereffects (3).svg

Experience reports

Anecdotal reports which describe the effects of this compound within our experience index include:

Additional experience reports can be found here:

Toxicity and harm potential

The toxicity of recreational propylhexedrine use has not been studied as extensively as that of amphetamine or methamphetamine but it is reasonable to assume that most if not all of the same risks apply.

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 propylhexedrine can be considered extremely 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 the effects of this compound likely occurs in the same general fashion as with amphetamine rapidly develops with prolonged and repeated use.[1][2] 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). Propylhexedrine presents cross-tolerance with all dopaminergic stimulants, meaning that after the consumption of propylhexedrine all stimulants will have a reduced effect.

Like with amphetamine and methamphetamine the evidence on effective treatments for dependence and abuse is limited.[3] In light of this, fluoxetine and imipramine appear to have some limited benefits in treating abuse and addiction[4]

In highly dependent amphetamine and methamphetamine abusers, "when chronic heavy users abruptly discontinue methamphetamine use, many report a time-limited withdrawal syndrome that occurs within 24 hours of their last dose".[5] Withdrawal symptoms in chronic, high-dose users are frequent, occurring in up to 87.6% of cases, and persist for three to four weeks with a marked "crash" phase occurring during the first week.[6] Methamphetamine withdrawal symptoms can include anxiety, drug craving, dysphoric mood, fatigue, increased appetite, increased movement or decreased movement, lack of motivation, sleeplessness or sleepiness, and vivid or lucid dreams.[7] Withdrawal symptoms are associated with the degree of dependence (i.e., the extent of abuse).[8] The mental depression associated with methamphetamine withdrawal lasts longer and is more severe than that of cocaine withdrawal.[9]. It is likely that propylhexedrine abuse is subject to these same outcomes.


Main article: Stimulant psychosis

Like with the abuse of methamphetamine, propylhexedrine abuse can result in a stimulant-induced psychotic state that may present with a variety of symptoms (e.g., paranoia, hallucinations, delusions), though likely to a lesser degree.[10][11] A review on treatment for amphetamine, dextroamphetamine, and methamphetamine abuse-induced psychosis states that about 5–15% of users fail to recover completely.[11][12] The same review asserts that, based upon at least one trial, antipsychotic medications effectively resolve the symptoms of acute amphetamine psychosis.[11]

Dangerous interactions

Although many psychoactive substances are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption.

Legal status


This legality section is a stub.

As such, it may contain incomplete or wrong information. You can help by expanding it.

  • United States - Propylhexedrine is a legal OTC drug. It is designed not to be recreationally used unless the user decides to bypass the manufacturer's intended design with which it was granted approval to market as a nasal decongestant. The simple consumption of this substance is not technically considered illegal.

See also

External links


  1. Efficacy of psychostimulant drugs for amphetamine abuse or dependence ( / NCBI) |
  2. Amphetamines, By Patrick G. O’Connor, MD, MPH, Yale University School of Medicine |
  3. Treatment for amphetamine dependence and abuse ( / NCBI) |
  4. Treatment for amphetamine dependence and abuse ( / NCBI) |
  5. Treatment for amphetamine withdrawal ( / NCBI) |
  6. Treatment for amphetamine withdrawal ( / NCBI) |
  7. Treatment for amphetamine withdrawal ( / NCBI) |
  8. Treatment for amphetamine withdrawal ( / NCBI) |
  9. Methamphetamine abuse ( / NCBI) |
  11. 11.0 11.1 11.2 Shoptaw, S. J., Kao, U., & Ling, W. (2009). Treatment for amphetamine psychosis. The Cochrane Library.
  12. Hofmann FG (1983). A Handbook on Drug and Alcohol Abuse: The Biomedical Aspects (2nd ed.). New York: Oxford University Press. p. 329. ISBN 9780195030570.
  13. Adderall Prescription info |
  14. Gillman, P. K. (2005). Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity. British Journal of Anaesthesia, 95(4), 434-441.