|Summary sheet: DXM|
|Common names||DXM, DMO, DM, Dex, Robitussin, Delsym, DexAlone, Duract|
|Routes of Administration|
DXM is the primary active ingredients in many common over-the-counter (OTC) cold and cough medicines, including generic drug labels and store brands. It is also used in other areas of medicine, ranging from pain relief to psychological applications. In its pure form, DXM occurs as a white powder, although it is most commonly consumed in tablet, capsule, or syrup forms.
In the United States and elsewhere, DXM has been noted for having a culture of recreational consumption as a legal, commonly-available, "OTC high." When exceeding label-specified maximum dosages, it acts as a serotonergic dissociative that produces potent and long-lived hallucinogenic effects with a strong "body load" that can range from pleasant to intolerable. In high doses, this produces effects similar to, yet distinct from, the dissociative states produced by other common dissociatives such as ketamine and phencyclidine (PCP).
Due to its powerful hallucinogenic and potential dependence-producing effects, it is strongly advised to take appropriate precautions and use harm reduction practices if using this substance.
- 1 History and culture
- 2 Chemistry
- 3 Pharmacology
- 4 Subjective effects
- 4.1 Physical effects
- 4.2 Visual effects
- 4.3 Cognitive effects
- 4.4 Auditory effects
- 4.5 Disconnective effects
- 4.6 Multi-sensory effects
- 4.7 Transpersonal effects
- 4.8 Afterglow
- 4.9 Plateaus
- 4.10 Experience reports
- 5 Usage
- 6 Toxicity and harm potential
- 7 Legal status
- 8 See also
- 9 External links
- 10 References
History and culture
This History and Culture section is a stub.
As such, it may contain incomplete or wrong information. You can help by expanding it.
DXM was first discovered in 1954 as part of US Navy and CIA-funded research on possible substitutes for codeine and dihydrocodeine. The purpose was to find a less sedating antitussive (cough suppressant) agent with a lower potential for dependence. Shortly after its approval by the FDA in 1958 as an over-the-counter antitussive, anecdotal reports of recreational use began to spread.
During the 1960s and 1970s, a tablet form preparation named "Romilar" was sold over-the-counter as a DXM-containing antitussive. DXM was excluded from the Controlled Substances Act of 1970 which allowed its sale to continue.
Romilar was taken off the OTC-market in 1975, as its rising popularity as a legal dissociative drug was recognized. After its removal many companies began to sell DXM preparations in syrup form, which created an unpleasant taste if consumed in large quantities, so as to make them unappealing for recreational use.
Dextromorphan is a dextrorotatory molecule of the morphinan class. It contains a phenanthrene core structure with one aromatic ring (benzene) bound to two saturated rings (cyclohexane). Additionally, it contains a saturated piperidine ring attached to R9 and R13 of the core structure. DXM is substituted at RN with a methyl group and at R3 with a methoxy group.
DXM acts as an NMDA receptor antagonist. NMDA receptors allow for electrical signals to pass between neurons in the brain and spinal column; for the signals to pass, the receptor must be open. Dissociatives close the NMDA receptors by blocking them. This disconnection of neurons leads to loss of feeling, difficulty moving, and eventually what is known as the “hole”.
The mechanism of action behind DXM is via multiple effects, including actions as a nonselective serotonin reuptake inhibitor, alpha-3 beta-4 nicotinic receptor antagonist and a sigma-1 receptor agonist.
At high doses, DXM can cause an increase in systolic and diastolic blood pressure along with an increase in heart rate. DXM also increases blood plasma levels of adrenocorticotropic hormone (ACTH) and corticosterone.
|Binding Sites||Binding Affinity Ki (nM)|
DXM is O-demethylated into Dextrorphan (DXO / D-3-hydroxy-N-methylmorphinan) by the CYP2D6 enzyme. DXM is also N-demethylated into 3-methoxymorphinan (MEM / Morphinan) by the CYP3A4 enzyme and to a lesser extent CYP3A5.
Dextrorphan and 3-methoxymorphinan are both metabolized into 3-hydroxymorphinan. Dextrorphan is N-demethylated by CYP3A4 and 3-Methoxymorphinan is O-demethylated by CYP2D6. CYP2D6 O-demethylation is more effective than CYP3A4 N-demethylation.
Dextrorphan is produced by O-demethylation of dextromethorphan through the CYP2D6 enzyme and contributes to the psychoactive effects of dextromethorphan. It is pharmacologically similar to that of dextromethorphan (DXM). However, dextrorphan is much more potent as an NMDA receptor antagonist as well as much less active as a selective serotonin reuptake inhibitor. It is also about 3-fold less potent of a α3β4 nicotinic receptor antagonist than DXM and has a lower affinity for sigma-1 receptors.
|Binding Sites||Binding Affinity Ki (nM)|
3-Hydroxymorphinan (also known as 3HM) is produced by O-demethylation of 3-methoxymorphinan by CYP2D6 and metabolization of dextrorphan by CYP3A4 and CYP3A5. 3-Hydroxymorphinan exhibits neuroprotective and neurotrophic effects.
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.
- Stimulation & Sedation - At recreational doses, DXM is predominantly stimulating, in so much as one cannot fall asleep while on it. However, it can produce waves of tiredness, or the desire to lay down with the eyes closed in a sleep-like state.
- Perception of bodily lightness - This creates the sensation that the body is floating and has become entirely weightless. This effect is strangely stimulating and encourages physical activities at low to moderate dosages by making the body feel light and effortless to move.
- Spontaneous physical sensations - The DXM "body high" is a sharp, pleasurable tingling sensation which can be localized to the hands, feet, and head. In lower doses, it can produce an empowering stimulated sensation.
- Appetite suppression
- Changes in felt bodily form
- Motor control loss - A loss of gross and fine motor control alongside balance and coordination is prominent within DXM and becomes especially strong at higher dosages. This means that one should be sitting down before the onset to prevent falling over and becoming injured.
- Spatial disorientation - A spinning sensation is commonly felt that can result in mild disorientation as if one were falling through a hole.
- Nausea - DXM can sometimes produce extreme nausea and vomiting, typically during the come up phase of the experience. This is more intense and consistent than the nausea produced by ketamine and MXE. This is likely not caused by the DXM itself, but rather by the medium which contains the DXM, which is usually syrup or gelatin capules.
- Temperature regulation suppression
- Increased blood pressure
- Increased heart rate
- Increased perspiration - This is the result of a combination of increased bodily temperature and temperature regulation suppression.
- Muscle spasms
- Itchiness - This effect is colloquially known as "robo-itch". Many users never experience this effect while some individuals can experience it quite intensely. It is caused by a histamine release.
- Cough suppression
- Pain relief
- Optical sliding
- Dizziness - Although uncommon, some people report dizziness under the influence of DXM.
- Gustatory hallucinations
- Physical autonomy
- Tactile suppression - This partially to entirely suppresses sense of touch, creating feelings of numbness within the extremities. It is responsible for the anesthetic properties of this substance.
- Pupil dilation
- Gait alteration - This is a common effect on DXM and is commonly referred to as "robo walking". As with itchiness, some users may never experience this effect while others may experience it quite intensly.
- Peripheral vision enhancement - This effect usually only occurs at low doses
- Frame rate enhancement - This effect is rare and occasionally experienced in the lower plateaus. It appears to be setting dependent.
- Double vision - This component is prevalent at moderate to heavy dosages and makes reading impossible unless one closes an eye.
- Pattern recognition suppression - This effect generally occurs at higher dosages and makes one unable to recognize and interpret perceivable visual data.
- Frame rate suppression
- Visual acuity suppression
- After images
- Drifting - Visual drifting has been reported to occur on DXM, although it is uncommon. This effect is unrealistic in appearance. The distortions fast and smooth in motion, and are fleeting in appearance.
- Environmental cubism
- Environmental orbism
- Perspective distortions
- Scenery slicing
- Visual haze
- Visual stretching
The visual geometry that can be experienced on DXM can be described as very bright, colorful, psychedelic and intricate when compared to that of ketamine or MXE. It does not extend beyond level 4 and can be comprehensively described through its variations as intricate in complexity, algorithmic in style, synthetic in feel, unstructured in organization, brightly lit in lighting, multicoloured in scheme, glossy in shading, soft in edges, small in size, slow in speed, smooth in motion, equal in rounded and angular corners, immersive in-depth and consistent in intensity.
At high dosages, DXM can produce a full range of high level hallucinatory states in a fashion that is less consistent and reproducible than that of many other commonly used psychedelics. These effects include:
- External hallucinations (autonomous entities; settings, sceneries, and landscapes; alterations in perspective and scenarios and plots) - In comparison to other dissociatives, this effect can occur at heavy dosages, but is extremely infrequent in comparison to the same effect found within deliriants. It can be comprehensively described through its variations as delirious in believability, autonomous in controllability and solid in style. The most common theme for this effect to follow is one of experiencing and talking to friends around oneself when they are not actually present.
- Internal hallucinations (autonomous entities; settings, sceneries, and landscapes; alterations in perspective and scenarios and plots) - In comparison to other dissociatives, this effect can occur at heavy dosages, but is considerably less common than the same effect found within psychedelics and deliriants. It can be comprehensively described through its variations as delirious in believability, fixed in style, equal in new experiences and memory replays in content, autonomous in controllability and solid in style.
The head space of DXM is often described as distinctly hallucinogenic, impairing, disorientating and generally less clear-headed in comparison to that of MXE and ketamine. The cognitive effects of DXM can be broken down into several separate subcomponents which are listed and described below:
- Anxiety suppression or Anxiety - Although DXM typically suppresses anxiety, it is also able to produce it in certain conditions.
- Conceptual thinking
- Cognitive euphoria - While states of cognitive euphoria are commonly reported, this effect can unpredictably manifest itself as cognitive dysphoria for no apparent reason, particularly at higher doses.
- Cognitive fatigue
- Creativity enhancement
- Decreased libido
- Déjà vu
- Delusions - This effect can occur spontaneously among some users and is more likely to occur at higher doses.
- Feelings of impending doom
- Ego inflation
- Dream potentiation
- Emotion enhancement - Though this effect isn't as consistent as it is with other commonly used hallucinogens it is more prominent than with most dissociatives.
- Immersion enhancement
- Increased libido - This is exclusively felt in low doses.
- Increased music appreciation
- Analysis suppression
- Memory suppression
- Novelty enhancement
- Personal bias suppression - This effect is not usually as pronounced as it is with other more commonly used hallucinogens such as LSD or psilocin.
- Personal meaning enhancement - This effect is typically only present in the lower plateaus and varies in its believability and content.
- Thought deceleration
- Time distortion - Time while on DXM often feels very stretched out, for example, it may feel like an hour has passed when in reality only ten minutes have passed.
- Tactile disconnection - Although this effect is present, it is usually not as powerful or as consistent as with ketamine or PCP.
- Visual disconnection - This eventually results in the DXM's equivalent of the "K-hole" or more specifically, holes, spaces and voids alongside of structures.
- Consciousness disconnection
- Synaesthesia - In its fullest manifestation, this is a very rare and non-reproducible effect. Increasing the dosage can increase the likelihood of this occurring, but seems only to be a prominent part of the experience among those who are already predisposed to synaesthetic states.
- The afterglow is a feeling that can occur within the 24 hours after the end of the experience. It can be described regarding its physical sensation as one of euphoria, rejuvenation, relaxation and a light bounciness. Regarding its cognitive effects, it often comes in the form as a loss of anxiety, feelings of content, and a noticeable increase in one's ability to appreciate music and other sensory stimuli that are sometimes accompanied with mild derealization or depersonalization.
The online DXM community has informally divided the types of experiences that can result from oral DXM administration into five "plateaus" which are characterized by qualitatively distinct effects that vary by their body-weight adjusted doses.
First Plateau (1.5 - 2.5 mg/kg) - The effects felt in the first plateau are usually not very intense. They can include but are not limited to: cognitive euphoria, increased music appreciation, time distortion, pupil dilation, and stimulation. First plateau is often described as a "drunk" feeling.
Second Plateau (2.5 - 7.5 mg/kg) - Most DXM users consider this the to be the most recreational plateau. The second plateau is more sedating than stimulating, euphoria and visual disconnection are more intense. Additional effects of the second plateau can include but are not limited to: wakefulness, physical euphoria, spatial disorientation. Many users of DXM do not proceed past the second plateau, as the desired effects are thought to be outweighed by the increasingly unpredictable adverse physical effects and "body load".
Third Plateau (7.5 - 15 mg/kg) - The effects of the third plateau can include but are not limited to: sedation, nausea, memory suppression and ego death, auditory hallucinations, internal hallucinations, cognitive dysphoria, anxiety, delusions, and all the effects of the second plateau.
Fourth Plateau (15 - 20 mg/kg) - Doses of DXM in this range and beyond are considered to be very dangerous and are associated with a high risk of injury and overdose, and are therefore advised against. The effects of the fourth plateau can include but are not limited to external hallucinations, complete disassociation, and all the effects of the third plateau, with greater intensity.
Fifth Plateau (also known as "Plateau Sigma") - A common method to experience the so-called "Plateau Sigma" is to take second plateau dose, followed by another second plateau dose three hours later, then at the peak of the second dose, take a fourth plateau dose. Plateau Sigma may also occur unintentionally from redosing. It is nearly always a very unpleasant and unpredictable experience. The experience can last from a day to four days. Plateau Sigma usually results in delirious hallucinations, dysphoria, delirium, psychosis, and anxiety. Plateau Sigma has a high potential to cause serotonin syndrome and is therefore strongly advised against.
Anecdotal reports which describe the effects of this compound within our experience index include:
- Experience:1000mg / 1200mg / 1400mg / 1600mg - heroic doses
- Experience:1064mgs - Fascinating DXM experience - Unusual effects
- Experience:250mg DXM - DXM Itch and Trip Report
- Experience:300mg DXM + 25mg DMT + Cannabis - A crazy night
- Experience:350mg DXM - A surprisingly profound experience
- Experience:354mg DXM, weed, nicotine - Descending into the void
- Experience:535mg - My First DXM Trip
- Experience:700mg - To the dextroverse.
- Experience:750mg - Experiencing Void; Dissociation Of Reality And Self
- Experience:DXM and Cannabis: 100mg - Unexpected Strong Trip
- Experience:Eine heftige Klatsche: 60ug LSD + 280mg DXM
Additional experience reports can be found here:
DXM is available in several different forms that can be found over the counter or online.
- Cough syrup is the most common form online and over the counter. Well-known brands include Benylin, DayQuil, Delsym, NyQuil, Robitussin, and Siltussin. Many of these products contain other medicines, including aspirin, acetaminophen, caffeine, guaifenesin or pseudoephedrine. Care should be taken when using these products to ensure that there is no overdose on other medicines in the DXM-containing product. Within the UK, Benylin dry coughs 7.5mg/5ml syrup (225mg dosage per 150ml bottle) is available behind the counter at every pharmacy. Generic brands are also available within these shops for a consistently lower price.
- Gel capsules and pills are available online and over the counter. Well-known brands include Benylin, Comtrex, Coricidin, DayQuil, Mucinex, NyQuil, and Robitussin. Many of these products contain other medicines, including aspirin, acetaminophen, caffeine, guaifenesin or pseudoephedrine. Care should be taken when using these products to ensure that there is no overdose on other medicines in the DXM-containing product.
- Pure powder is available online. This is the safest way to use DXM, as there is no danger of overdose from secondary chemicals.
Grapefruit juice is reported to be effective at potentiating and enhancing the effects of DXM. If one drinks approximately one glass of white grapefruit juice hourly the day before the trip, the effects will be considerably stronger and more intense. For users who are drinking store bought syrup, this is useful as it means drinking less syrup.
The grapefruit juice acts on DXM by inhibiting the activity of cytochrome P450 enzymes of the 3A and 1A groups. DXM is converted to DXO by this same enzyme, only with different groups. Therefore, with enough grapefruit juice, the overall trip should be significantly more intense, as the DXM is converted into DXO at a faster rate.
Preparation methods for this compound within our tutorial index include:
Toxicity and harm potential
The toxicity and long-term health effects of recreational DXM use in humans do not seem to have been studied in any scientific context and the exact toxic dosage is unknown. This is because DXM has very little history of human usage.
Anecdotal evidence from people who have tried DXM 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). Independent research should always be done to ensure that a combination of two or more substances is safe before consumption.
Despite early speculation that DXM (due to similarities with PCP) may cause neurotoxicity and Olney's lesions, it has not been shown to cause this effect in animals , However, many chronic users report significant issues with memory, attention, and mood that persist for many months after stopping usage. In rats, oral administration of dextromethorphan did not cause neurotoxic effects in laboratory tests. Oral administration of dextromethorphan repeatedly during adolescence, however, has been shown to impair learning in those rats during adulthood.
It is strongly recommended that one use harm reduction practices when using this substance.
Tolerance and addiction potential
As with other NMDA receptor antagonists, the chronic use of DXM 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 DXM 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). DXM presents cross-tolerance with all dissociatives, meaning that after the consumption of DXM all dissociatives will have a reduced effect.
Additionally, some users report an irreversible, permanent tolerance to DXM, which develops over a long period of time and is thought to correlate with the number of doses a person has ingested throughout their lifetime. There is a supposed "50 trip limit", after which the rewarding and unique effects of DXM disappear permanently. The pharmacological mechanism for this is unknown, although it may be indicative of neurotoxicity.
A formal survey of dextromethorphan users showed that more than half of users reported experience of the following withdrawal symptoms individually for the first week after long-term/addictive dextromethorphan use: fatigue, apathy, flashbacks, and constipation. Over a quarter reported insomnia, nightmares, inability to feel pleasure, impaired memory, attention deficit and decreased libido. Rarer side effects included panic attacks, impaired learning, tremor, yellowing of the skin, hives and muscle pain. Frequent and long-term usage at very high doses could lead to toxic psychosis and other permanent psychological problems.
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.
- Stimulants - This combination can potentiate the anxiety-inducing, manic, delusional and disinhibiting aspects of dissociatives, particularly those without pronounced motor and consciousness-suppression components like ketamine as this can increase the likelihood of a panic event or psychotic episode.
- Prominent examples include PCP and its analogs 3-MeO-PCP, MXE, and the diarylethylamine dissociatives like diphenidine or ephenidine. There is also evidence that suggests that combining these two increases their neurotoxicity. Anecdotally, worsened comedowns are also commonly reported when these two classes of substances are combined.
- Depressants - Because both depress the respiratory system, this combination can result in an increased risk of suddenly falling unconscious, vomiting and choking to death from the resulting suffocation. If nausea or vomiting occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it. Also, this combination will produce a combined depressant effect which can cause dangerous levels of respiratory depression.
- Stimulants - A dangerous rise in blood pressure and heart rate can occur when DXM is combined with a stimulant such as amphetamine or cocaine.
Serotonin syndrome risk
Combinations in the list below may increase the amount of neurotransmitters such as serotonin and dopamine to dangerous or even fatal levels.
- MAOIs such as syrian rue, banisteriopsis caapi, 2C-T-2, 2C-T-7, αMT, and some antidepressants
- Serotonin releasers such as MDMA, 4-FA, MDAI and αMT
- Selective serotonin re-uptake inhibitors (SSRIs)
- Serotonin-norepinephrine reuptake inhibitors (SNRIs)
- Modafinil induces the CYP3A4 enzyme that DXM, and its metabolite DXO, are metabolized by.
- DXM has been shown to prevent and reverse morphine tolerance while also increasing analgesic effects as well as potentiating the analgesic activity of NSAIDs, naproxen, piroxicam, etodolac, diclofenac, and ketorolac.
This legality section is a stub.
As such, it may contain incomplete or wrong information. You can help by expanding it.
DXM is available either over the counter or by prescription in most countries. Some countries require the purchaser to be over 16, 18 or 21. However, it is easily accessible to legally purchase in a variety of forms online.
- Canada: Dextromethorphan is listed as specifically exempt from the Controlled Drugs and Substances Act:
"Schedule I . . . 10 Morphinans, their salts, derivatives and salts of derivatives including: . . . but not including (10) Dextromethorphan (d-1,2,3,9,10, 10a-hexahydro-6-methoxy-11-methyl-4H-10,4a-iminoethanophenanthren) and its salts . . .". Dextromethorphan is available OTC in Canada and can legally be obtained in powder form.
- Germany: Dextromethorphan is not listed in the "Betäubungsmittelgesetz" (Federal Law on Narcotics). Sales of DXM containing medications are restricted to pharmacies. DXM containing preparations are available at pharmacies without a prescription.
- Mexico: Dextromethorphan is not listed in the General Health Law (Ley General de Salud), which specifies which substances represent a risk to public health. It is also listed in the Reference Medicine Listing as a General Health Law article 226 fraction VI drug, which means it can be freely sold even in businesses that weren't legally registered as pharmacies. In practice, this translates into DXM-only syrups being available off-the-shelf and without prescription at any supermarket with a pharmacy section.
- Russia: Dextromethorphan is a schedule III controlled substance.
- Switzerland: Dextromethorphan is listed as a "Abgabekategorie C" pharmaceutical, which is sold exclusively in pharmacies without a prescription but needs approval of a medicinal.
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- Induction of heat shock protein HSP-70 in rat retrosplenial cortex following administration of dextromethorphan | Induction of heat shock protein HSP-70 in rat retrosplenial cortex following administration of dextromethorphan
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- Impairments in water maze learning of aged rats that received dextromethorphan repeatedly during adolescent period | http://en.wikipedia.org/wiki/Recreational_use_of_dextromethorphan#Risks_associated_with_use
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- Controlled Drugs and Substances Act (S.C. 1996, c. 19) | http://laws-lois.justice.gc.ca/PDF/C-38.8.pdf
- "Anlage I-III", BTMG | http://www.gesetze-im-internet.de/btmg_1981/
- § 43 AMG | http://www.gesetze-im-internet.de/amg_1976/
- Russian controlled substances lists | http://base.garant.ru/12112176/