Propylhexedrine

What it is

Propylhexedrine is a synthetic cyclohexylamine: chemically methamphetamine with the benzene ring replaced by a saturated cyclohexyl ring. It is the active ingredient of the Benzedrex nasal inhaler, which the current US label states contains 175 mg of propylhexedrine in a device meant to be sniffed. It replaced amphetamine sulfate in that inhaler in 1949 precisely because amphetamine was being extracted and abused. In Europe it was also sold as an appetite suppressant, Obesin, at approved doses of 5 to 30 mg. It is not a controlled substance in the United States.

What the research says

As a nasal decongestant, propylhexedrine has almost no modern outcome evidence. The one controlled human study found is from 1982 and showed nasal airway resistance fell for 120 minutes after inhalation; the 2016 Cochrane review of nasal decongestants used alone included no propylhexedrine trial at all. What the literature on this drug is actually about is misuse. There is a documented record going back to the 1970s of psychosis, myocardial infarction, pulmonary hypertension, brainstem injury and sudden death from swallowing or injecting the contents of the inhaler, including a series of 15 deaths investigated by one medical examiner's office, and a 2024 case of lasting neurological damage after oral misuse.

Evidence grade: Limited evidence.

How it works

Drug class: Cyclohexylamine indirect-acting sympathomimetic amine; a topical nasal decongestant used in an inhaler, and structurally an amphetamine analogue lacking the aromatic ring

Propylhexedrine is breathed in through the nose from an over-the-counter nasal inhaler that holds drug-soaked cotton rods. In the nose it stimulates alpha-adrenergic receptors, which narrows the vessels of the nasal lining and so reduces swelling and congestion. At the much higher doses reached when people dismantle the inhaler and swallow or inject its contents, it also releases dopamine, noradrenaline and serotonin from nerve terminals in the way amphetamines do, which is why it is misused. A 2018 emergency medicine review states that, compared with amphetamine, it is relatively more effective at promoting peripheral adrenergic stimulation than dopaminergic and serotonergic release. (Source 1)

What it is used for

• One 1982 study measured nasal airway resistance falling from baseline control values for 120 minutes after inhaled propylhexedrine; it reports no sample size, no dose and no randomisation or blinding. The 2016 Cochrane review of nasal decongestant monotherapy included no propylhexedrine trial, so there is effectively no modern randomised outcome evidence for this use. Evidence: limited. (Source 2)
• A 2020 review records approved European anorectic doses of 5 to 30 mg for a product marketed as Obesin, but no efficacy trial for this use was found in the searches run. The US over-the-counter monograph lists propylhexedrine only as a topical nasal decongestant active ingredient (21 CFR 341.20(b)(9)); the review prints nothing about US approval for appetite suppression. Evidence: unknown. (Source 3)
• A 2020 review records oral doses of 100 to 300 mg in misuse, and online users reporting 125 mg to 1250 mg; there is no therapeutic evidence for any of it. The documented outcomes each come from their own source: psychosis, myocardial infarction, pulmonary vascular disease, pulmonary hypertension and sudden death (a 1979 series of 15 deaths, a 1986 series and a 2012 case report); brainstem dysfunction and transient diplopia after intravenous use (the 1986 series of 7 patients); and lasting ataxia after a single oral misuse (a 2024 case report). The 2012 paper records that no formal study of its dependence potential exists. Evidence: not-supported. (Source 3)

Interactions

• Kratom (Mitragyna speciosa, mitragynine) (case reports): Two published cases involve propylhexedrine taken together with kratom, a herbal product sold as a supplement: an accidental death certified as propylhexedrine toxicity in which mitragynine was also measured in blood, and the 2024 case of lasting neurological injury in which expanded drug testing was positive for mitragynine. In the death, the medical examiner could not judge how much the kratom contributed because no reference blood concentrations exist. (Source 4)
• L-arginine (case reports): In the 2024 case of neurological injury, the person deliberately took 1 g of the amino acid supplement L-arginine at the same time as the propylhexedrine, on the theory from an online forum that it would offset the vasoconstriction. He still developed what the authors describe as T2 enhancement concerning for vasogenic oedema on MRI, which they suggest in their discussion may indicate vasospasm. Nothing in the case suggests the supplement protected him, but this is a single case, expanded drug testing was also positive for mitragynine and THC, and one case with several exposures cannot show what L-arginine does. (Source 5)
• Acidic drinks such as cola and lemon juice (case reports): Acidic liquids are used in the documented misuse route: the drug-soaked cotton wick from the inhaler is soaked in an acidic drink such as cola or lemon juice to extract the propylhexedrine, which is then swallowed or injected. This is a food interaction only in the sense that an everyday drink is what makes the extraction work. (Source 6)
• Monoamine oxidase inhibitors (MAOIs) (theoretical): Propylhexedrine works by reversing the transporters that normally take noradrenaline, dopamine and serotonin back into nerve terminals, so it releases those transmitters into the synapse. That is the same mechanism that makes indirect sympathomimetics dangerous with an MAOI, but no case report or study of propylhexedrine with an MAOI was found in the literature searched, so this is reasoning from mechanism and not a documented interaction. The MAOI warning in the US monograph is attached to oral nasal decongestants, at 21 CFR 341.80(c)(1)(i)(D); the warnings for topical nasal decongestants at 341.80(c)(2) contain no MAOI language at all, so nothing in the monograph attaches that precaution to an inhaler. (Source 7)
• Other co-ingested drugs during misuse (case reports): In the documented fatal case, acetaminophen, morphine and promethazine were also detected in urine alongside propylhexedrine and mitragynine, which is typical of the polysubstance context in which these deaths occur and makes attribution to any one drug difficult. (Source 4)
• Alcohol (theoretical): No clinical study or case report of an interaction between propylhexedrine and alcohol was found in the searches run. What is documented is that there is no antidote for propylhexedrine intoxication and that treatment is supportive, so any additional intoxicant adds to a picture that cannot be reversed pharmacologically. (Source 8)

Stopping it

• For the labelled nasal use, the stopping rule is a three-day limit rather than a taper, with the label stating that frequent or prolonged use may make congestion recur or worsen. (Source 9)
• For people who have been misusing it, the literature offers nothing: there is no antidote for acute intoxication, care is supportive, and no guidance exists for staying off it. (Source 8)
• Withdrawal after heavy use has only been described through online user reports: discomfort, low mood and headache on stopping, with no clinical follow-up establishing how long it lasts. (Source 10)

What goes wrong

Propylhexedrine was implicated in 15 deaths investigated by one county medical examiner's office from 1973 onwards, twelve of them attributable to intravenous abuse of the contents of the inhaler, with right ventricular hypertrophy in nine of those twelve. (Source 11)

• Case series, Moderate certainty.
• Size: 15 deaths, 12 from intravenous abuse.
• Who: people whose deaths were investigated by the Dallas County Medical Examiner from 1973 onwards.
• How long: deaths were sudden.
• Result: pulmonary oedema, foreign body granulomas, fibrosis and evidence of pulmonary hypertension were frequent post-mortem findings; right ventricular hypertrophy in 9 of the 12 intravenous cases; two homicides and one suicide were also propylhexedrine-related.
• Funding: not stated.

Propylhexedrine was implicated in 15 deaths investigated by the Dallas County Medical Examiner since 1973. Twelve of the deaths were attributable to intravenous abuse of the contents of the Benzedrex® inhaler.

Injecting extracted propylhexedrine caused brainstem damage in two young adults and transient double vision in five more, with the deficits in the two severe cases lasting many months. (Source 12)

• Case series, Low certainty.
• Size: 7 patients.
• Who: young adults injecting propylhexedrine extracted from Benzedrex inhalers by heating with hydrochloric acid.
• How long: diplopia within seconds of injection; deficits in two patients persisted for many months.
• Result: all 7 had transient diplopia; one had a right internuclear ophthalmoplegia; another had a depressed right gag reflex and paralysis of the right half of the tongue.
• Funding: not stated.

We are reporting 2 cases of definite brainstem dysfunction and 5 cases of transient diplopia secondary to IV abuse of Benzedrex.

A 21-year-old who swallowed propylhexedrine extracted from an inhaler into lemon juice developed MRI changes the authors describe as concerning for vasogenic oedema, and was discharged to rehabilitation with unresolved coordination problems. (Source 5)

• Case report, Low certainty.
• Size: 1 patient.
• Who: a 21-year-old man following extraction instructions from an online forum.
• How long: symptoms began about 12 hours after ingestion; deficits unresolved at discharge on hospital day 6.
• Result: dizziness, intractable vomiting, diplopia, ataxia, dysmetria and horizontal nystagmus; MRI showed T2 enhancement suggesting vasogenic oedema of the right posterior limbs of the internal capsule extending into midbrain, cerebellar peduncles and cerebellar white matter; blood was positive for propylhexedrine on liquid chromatography quadrupole time-of-flight mass spectrometry.
• Funding: not stated.

On hospital day 6, the patient was discharged to physical rehabilitation with unresolved dysmetria and ataxia.

A 2020 review lists raised heart rate and blood pressure lasting for prolonged periods, arrhythmias at abuse doses, hyperthermia, intestinal impaction and aspiration from parachuting the extracted drug, and stimulant psychosis among the harms of propylhexedrine misuse. (Source 10)

• Expert review, not systematic, Low certainty.
• Size: all human literature from 1975 to 2020 plus user forum reports.
• Who: people misusing propylhexedrine from nasal inhalers.
• How long: effects reported from both single and chronic use.
• Result: increased heart rate and blood pressure lasting prolonged periods, bronchodilation, dehydration, urinary frequency, hyperthermia, perspiration, bruxism, temporary erectile dysfunction, arrhythmias at abuse doses, intestinal impaction and aspiration through parachuting (wrapping the extracted drug and swallowing the package), and stimulant-induced psychosis with paranoia, hallucinations, delusions and agitation.
• Funding: not stated; a case report with literature review, and part of the adverse effect list is taken from online user forums rather than clinical records.

One publication presented 15 cases of intravenous propylhexedrine-related deaths, majority being associated with anatomical indications of right ventricular hypertrophy and pulmonary hypertension at autopsy ⁶.

A death was certified as propylhexedrine toxicity in a man who had also taken kratom, with measured blood levels of both substances. (Source 4)

• Case report, Low certainty.
• Size: 1 death.
• Who: a man found dead at home with computer records of kratom and of a procedure to concentrate propylhexedrine from over-the-counter inhalers.
• How long: not applicable.
• Result: 1.7 mg/L propylhexedrine and 0.39 mg/L mitragynine in blood; acetaminophen, morphine and promethazine also in urine; cause of death ruled propylhexedrine toxicity, manner accidental; the medical examiner excluded mitragynine toxicity from the cause because no reference concentrations exist.
• Funding: research support recorded as non-US government.

Toxicology results revealed the presence of 1.7 mg/L propylhexedrine and 0.39 mg/L mitragynine in his blood.

A 2012 case report of propylhexedrine dependence records that no formal study of its dependence potential has ever been done; it dates concern about abuse potential to the 1980s, which led to a review by the WHO Expert Committee on Drug Dependence. (Source 13)

• Case report, Low certainty.
• Size: 1 case of dependence, with a historical review.
• Who: people using over-the-counter Benzedrex.
• How long: not applicable.
• Result: cases of psychosis, myocardial infarction, pulmonary vascular disease, pulmonary hypertension and sudden death are described as well documented but usually as single case reports; growing concerns during the 1980s led to review by the WHO Expert Committee on Drug Dependence; no formal dependence study exists. The 1949 date in this abstract belongs to amphetamine sulfate, the ingredient propylhexedrine replaced in Benzedrex, and the reports of widespread abuse at that date are of amphetamine sulfate rather than of propylhexedrine.
• Funding: not stated.

no formal studies of the dependence potential of propylhexedrine exists to date

What is reported about stopping propylhexedrine after heavy use comes from online user forums, not from clinical follow-up, and the duration of withdrawal symptoms is unknown. (Source 10)

• Expert review, not systematic, Very low certainty.
• Size: not quantified; user forum reports.
• Who: people who had been misusing propylhexedrine.
• How long: unknown.
• Result: generalized discomfort, dysphoria and headache on abrupt cessation, with duration unknown; a separate description of a pronounced comedown on prolonged use includes anxiety, appetite suppression, cognitive fatigue, irritability, depression, motivation suppression, thought deceleration and insomnia.
• Funding: not stated; the source for this specific observation is online user forums, which is the weakest kind of evidence in this write-up.

Upon abrupt cessation of use, online users report generalized discomfort, dysphoria and headache, however duration of such symptoms is unknown.

A 2020 review records that propylhexedrine is not chemically classified as an amphetamine and was therefore left out of the Combat Methamphetamine Epidemic Act of 2005, that it remains available over the counter or online with no restriction on amount, and that as of August 2020 it remained unscheduled. (Source 14)

• Expert review, not systematic, Low certainty.
• Size: not applicable.
• Who: US purchasers of propylhexedrine inhalers.
• How long: not applicable.
• Result: excluded from the Combat Methamphetamine Epidemic Act of 2005, which tightened scrutiny of ephedrine, pseudoephedrine and norpseudoephedrine products; available over the counter or online with no restriction on amount; still unscheduled as of August 2020 despite WHO reviews in 1985, 1989 and 1991.
• Funding: not stated.

Limit of this finding: Three things to hold loosely here. The review's own sentence about scheduling contradicts itself: it says the World Health Organization Expert Committee on Drug Dependence first reviewed scheduling propylhexedrine in 1985, “followed by reviews in 1985, 1989 and 1991”, and 1985 cannot be both the first review and one of the reviews that followed it. The review also does not say that the non-amphetamine classification is why the drug remains unscheduled - it gives that classification only as the reason for exclusion from the 2005 Act - and the sentence that says it remains unscheduled follows a sentence about the World Health Organization Expert Committee and names no country, so it should not be read as a statement about United States scheduling specifically. And the legal status is dated: the review states it as of August 2020, so nothing here should be read as a statement about the law today.

Propylhexedrine therefore remains easily available for purchase over-the-counter or online with no restriction on amount.

The US over-the-counter monograph requires propylhexedrine inhalers to be labelled with a three-day limit and a statement that frequent or prolonged use may make congestion recur or worsen. (Source 15)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: adults using US-labelled propylhexedrine inhalers.
• How long: monograph limit of 3 days.
• Result: required warning text identical to that for the imidazoline nasal sprays, with a 3-day cap and the rebound statement.
• Funding: US federal regulation; a regulator's position, not a trial.

For products containing propylhexedrine identified in § 341.20(b)(9) when used in an inhalant dosage form and when labeled for adults.

A 2018 emergency medicine review describes propylhexedrine toxicity as mimicking that of the amphetamines but with seemingly more profound end-organ complications from its relatively higher hypertensive and vasoconstrictive effects, especially with intravenous injection. (Source 16)

• Expert review, not systematic, Low certainty.
• Size: not applicable.
• Who: people presenting to emergency departments after misuse.
• How long: not applicable.
• Result: sympathomimetic toxidrome with profound tachycardia and hypertension; reported end-organ damage includes cardiogenic shock and pulmonary oedema in a 22-year-old with a large anterior myocardial infarction, and brainstem dysfunction with ophthalmoplegia; one Texas case series links injection to 15 sudden deaths. The review attributes these to the case literature, so they are case reports rather than incidence data.
• Funding: not stated.

Toxicity of propylhexedrine mimics that of the amphetamines, but with seemingly more profound end-organ complications from its relatively higher hypertensive and vasoconstrictive effects, especially with intravenous injection.

What the evidence supports

In the only human decongestant study found for propylhexedrine, nasal airway resistance fell from baseline control values for 120 minutes after inhaling it, in people congested by an upper respiratory infection or allergic rhinitis. (Source 2)

• Cohort study, Very low certainty.
• Size: not stated in the abstract.
• Who: subjects with nasal congestion due to acute upper respiratory infection or allergic rhinitis.
• How long: measured for 120 minutes after inhalation.
• Result: nasal airway resistance statistically decreased from control values for 120 minutes after propylhexedrine vapours; responses were the same in the upper respiratory infection and allergic rhinitis groups. The abstract gives no sample size, no dose and no randomisation or blinding detail, and its control values are the baseline measurements rather than a separate control group.
• Funding: recorded as research support, US Government, non-Public Health Service.

Rn was statistically decreased from control values for 120 minutes after propylhexedrine vapors.

What the evidence does not support

The same 1982 study could show no effect of the aromatic oils added to the inhaler, and found the subjective congestion rating scale was insensitive and unreliable against the objective measurement. (Source 2)

• Cohort study, Very low certainty.
• Size: not stated in the abstract.
• Who: subjects with nasal congestion due to upper respiratory infection or allergic rhinitis.
• How long: measured for 120 minutes after inhalation.
• Result: no demonstrable effect of the aromatic oils; the subjective rating scale had reduced sensitivity and poor reliability compared with objective nasal airway resistance.
• Funding: recorded as research support, US Government, non-Public Health Service.

Responses were the same for subjects with URI and allergic rhinitis, and no effect of the aromatic oils could be demonstrated.

The 2016 Cochrane review of nasal decongestants used alone for the common cold included no trial of propylhexedrine, so this drug contributes nothing to the systematic-review evidence for decongestants. (Source 17)

• Systematic review, Moderate certainty.
• Size: 15 trials, 1838 participants, none using propylhexedrine.
• Who: adults and children with the common cold.
• How long: single-dose and multi-dose studies, follow-up 1 to 10 days.
• Result: the drugs used were pseudoephedrine (9 studies), oxymetazoline (3), phenylpropanolamine, norephedrine and xylometazoline; propylhexedrine does not appear, so no pooled estimate of its benefit or harm exists.
• Funding: research support recorded as non-US government; a Cochrane review.

Nine studies used pseudoephedrine and three studies used oxymetazoline. Other decongestants included phenylpropanolamine, norephedrine and xylometazoline.

Where the research disagrees

Whether propylhexedrine's abuse potential is a public health concern

• Smith and colleagues, 1988, as summarised in a 2020 review, not stated: the review gives no design for this position, and the paper it cites (Smith DE, Wesson DR, Sees KL, Morgan JP, J Psychoactive Drugs 1988;20:441-442, PMID 2907528) has no abstract on PubMed or Europe PMC and is indexed only as Journal Article, Case Reports, so what the 1988 argument rested on could not be verified: Smith et al.’s 1988 paper argued that despite the increased prevalence of cocaine and methamphetamine abuse at that time, there were no risk indicators of propylhexedrine abuse, and that it did not pose a significant public health concern at that time ¹. (Source 18)
• Authors of the 2020 Cureus case report and literature review, case report plus a review of English-language human literature published between 1975 and 2020, with select animal studies, and of online user forums: As seen in our paper, there is plenty of evidence from literature and user forums to suggest there are psychoactive effects comparable to amphetamines and inferior to that of methamphetamines with doses in the 100-300 mg range. (Source 18)

How much

• Reference intake: There is no reference intake for a drug. The US Drug Facts label for the Benzedrex inhaler (DailyMed SPL version 2, published 9 December 2024) gives as its directions: “adults and children 6 to 12 years of age (with adult supervision): two inhalations in each nostril not more than every two hours.” and “children under 6 years of age: consult a doctor”. That is the manufacturer's and regulator's position, recorded as a position. (Source 9)
• Upper limit: There is no upper intake level. The US Drug Facts label for the Benzedrex inhaler (DailyMed SPL version 2, published 9 December 2024) states that the device contains “Propylhexedrine 175 mg” in total, and the US monograph caps labelled use at three days, requiring the warning “Do not use this product for more than 3 days. Use only as directed. Frequent or prolonged use may cause nasal congestion to recur or worsen. If symptoms persist, consult a doctor.” The figure for how much the device holds is not settled: a 2020 review of propylhexedrine misuse and a 2024 case report both describe inhalers containing 250 mg each. Both figures are reported here as their own sources state them, with the 175 mg figure dated to the December 2024 label; no source we read reconciles them. (Source 9)
• Studied: The 1982 controlled study gave propylhexedrine by inhalation, with and without aromatic oils, and measured nasal airway resistance for 120 minutes. (Source 2)
• Studied: A 2020 review calculates that the labelled regimen of two inhalations per nostril every two hours delivers 0.4 to 0.5 mg of propylhexedrine, and records approved European anorectic doses of 5 to 30 mg. The same review records that doses of 100 to 300 mg taken orally are those used in misuse, not in treatment, and that online users report ingesting 125 mg to 1250 mg. (Source 3)

A common belief, and what the research shows

The belief: Because it is sold over the counter without any restriction, propylhexedrine must be a mild and safe stimulant.

What the research shows: Being unscheduled is a legal fact, not a safety finding. A 2020 review states that propylhexedrine “remains easily available for purchase over-the-counter or online with no restriction on amount” precisely because it “is not chemically classified as an amphetamine”, and that “Early literature underestimated the abuse potential of propylhexedrine.” The published record includes 15 deaths investigated by one medical examiner's office, brainstem injury, and lasting ataxia after a single oral misuse. A 2012 paper records that “no formal studies of the dependence potential of propylhexedrine exists to date”, so the absence of a schedule reflects an absence of study as much as an absence of risk.

Questions and answers

What is it?

Propylhexedrine is a manufactured stimulant-type drug, the active ingredient of the Benzedrex nasal inhaler. A 2018 emergency medicine review describes it as chemically similar to methamphetamine, lacking the aromatic ring. It was put into the inhaler in 1949 to replace amphetamine sulfate, which was being abused. It is sold over the counter in the United States, and a 2020 review records that it remained unscheduled as of August 2020. (Source 13)

What does it do in the body?

Sniffed from the inhaler at the labelled dose, it stimulates alpha-adrenergic receptors in the nasal lining and narrows the blood vessels there, which reduces swelling and congestion. At the far larger doses reached by swallowing or injecting the inhaler contents it also releases dopamine, noradrenaline and serotonin from nerve endings, as amphetamines do. Its effects on blood vessels and blood pressure are relatively stronger than its effects on the brain. (Source 1)

Is it good or bad for you?

For the labelled nasal use the evidence is one 1982 study in which nasal airway resistance fell for 120 minutes, and no trial at all in the 2016 Cochrane review of decongestants. For misuse the evidence of harm is substantial and consistent across five decades: the 1986 report quoted here describes psychosis, myocardial infarction, pulmonary vascular disease, pulmonary hypertension and sudden death as well documented in the medical literature, and adds its own cases of brainstem dysfunction. The dose separating the two is large, which is why an inhaler sniffed as labelled and an inhaler taken apart and swallowed are completely different propositions. (Source 12)

How do you get more of it?

Not a question that applies in the usual sense: propylhexedrine is a manufactured drug, not something the body makes or obtains from food. In the United States it is listed as a topical nasal decongestant active ingredient in the over-the-counter monograph and is sold as an inhaler. A 2020 review notes that it remains available over the counter or online with no restriction on amount, which is how the misuse literature arises. (Source 14)

If it is harmful, what reduces it?

In acute poisoning there is no antidote, and treatment is symptomatic and supportive: managing severe agitation, fast heart rate, high blood pressure, high temperature, seizures and the possibility of heart attack, stroke, bowel obstruction or pulmonary hypertension. For getting off it after prolonged misuse, no guidance exists at all. (Source 8)

Why might someone be low in it or missing it?

Does not apply. Propylhexedrine is a manufactured drug ingredient, so there is no deficiency and no body store that can run low. The US monograph lists it among topical nasal decongestant active ingredients to be used within set dosage limits and dosage forms. (Source 19)

Which whole foods contain it or feed it?

None. Propylhexedrine is a synthetic cyclohexylamine and is not a constituent of any food. The only food connection in the literature is an unwanted one: acidic drinks such as cola or lemon juice are used to extract the drug from the inhaler wick for misuse. (Source 6)

What happens if you do not have it?

Nothing happens from not having propylhexedrine; there is no deficiency state. Not using it means a blocked nose is untreated by this particular drug, and the evidence that it adds anything beyond 120 minutes of reduced nasal resistance is absent. The 2016 Cochrane review of decongestant monotherapy included no propylhexedrine trial, and concluded only that multi-dose decongestants may have a small effect on how blocked adults feel. (Source 20)

How can you test for it?

Routine drug testing does not pick it up: the 2020 review states that given its chemical structure, use can evade detection on standard toxicology screens. Where it has been measured it took specialist methods: gas chromatography-mass spectrometry of a derivative in the 2011 forensic death case, and liquid chromatography quadrupole time-of-flight mass spectrometry of blood in the 2024 neurological case, where it was found only after expanded testing. There is no routine clinical test, and no test for the harms it causes. (Source 18)

References

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2. The Annals of Otology, Rhinology, and Laryngology. Nasal decongestant effect of propylhexedrine - abstract. 1982. PMID 6176171, DOI 10.1177/000348948209100124. Read the source
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5. Journal of Medical Toxicology. Neurologic Deficits Following Oral Misuse of the Nasal Decongestant Propylhexedrine - Case report. 2024. PMID 39103667, DOI 10.1007/s13181-024-01025-w. Read the source
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8. Cureus. Abuse, Toxicology and the Resurgence of Propylhexedrine - Discussion, 'Management'. 2020. PMID 33178521, DOI 10.7759/cureus.10868. Read the source
9. B.F. Ascher and Co., Inc. / DailyMed (US National Library of Medicine), SPL version 2 published 9 December 2024. Benzedrex (propylhexedrine) inhalant - US Drug Facts label: active ingredient, Uses, Warnings, Do not use, Stop use, pregnancy, Keep out of reach of children, Directions, Other information. 2024. Read the source
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11. The American Journal of Medicine. Intravenous propylhexedrine (Benzedrex) abuse and sudden death - abstract. 1979. PMID 37732, DOI 10.1016/0002-9343(79)90063-9. Read the source
12. The Canadian Journal of Neurological Sciences. Intravenous abuse of propylhexedrine (Benzedrex) and the risk of brainstem dysfunction in young adults - abstract. 1986. PMID 2877725, DOI 10.1017/s0317167100036696. Read the source
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15. Code of Federal Regulations, title 21, volume 5, revised as of 1 April 2024 (US Government Publishing Office). 21 CFR 341.80(c)(2) - Labeling of nasal decongestant drug products: warnings for topical nasal decongestants, subparagraphs (i) to (x) complete. 2024. Read the source
16. Open Access Emergency Medicine (Dove Medical Press). When good times go bad: managing 'legal high' complications in the emergency department - section 'Propylhexedrine', second paragraph. 2018. PMID 29302196, DOI 10.2147/oaem.s120120. Read the source
17. Cochrane Database of Systematic Reviews (Wiley). Nasal decongestants in monotherapy for the common cold (Cochrane Review) - Main results, trials and drugs included. 2016. PMID 27748955, DOI 10.1002/14651858.cd009612.pub2. Read the source
18. Cureus. Abuse, Toxicology and the Resurgence of Propylhexedrine - penultimate paragraph of the Discussion. 2020. PMID 33178521, DOI 10.7759/cureus.10868. Read the source
19. Code of Federal Regulations, title 21, volume 5, revised as of 1 April 2024 (US Government Publishing Office). 21 CFR 341.20 - Nasal decongestant active ingredients. 2024. Read the source
20. Cochrane Database of Systematic Reviews (Wiley). Nasal decongestants in monotherapy for the common cold (Cochrane Review) - Authors' conclusions. 2016. PMID 27748955, DOI 10.1002/14651858.cd009612.pub2. Read the source