Romilar 1968 Ad

Dextromethorphan (also known as 'DXM', 'DM' or 'robo') is an over-the-counter antitussive (cough treatment) which when taken at doses exceeding the recommended therapeutic range becomes a powerful dissociative drug which also has some psychedelic properties.

While DXM can be used safely it is not an inherently safe drug. Repeated use within a short period of time, combination with certain types of drugs, certain genetic factors and the prevalence of other active ingredients which become harmful at needed doses found in many brands of cough medication make for a chemical which must be used with caution.

The high is not for everyone; it is said to loosely follow the rule of thirds: one third hates it, one third doesn't care, and one third like it. It should not be underestimated as a hallucinogenic, at higher dosages mimic high doses of ketamine but with more psychedelic properties.

DXM manifests its effects in a series of plateaus, with dose determining which plateau (and subsequently which effects) one will experience. Lower dose plateaus can be well suited to relaxation, light social interaction and listening to music, however higher doses result in a more encompassing dissociative experience which does not lend itself to attentive presence. At high doses it's common to have strong hallucinations, experiences of detachment, depersonalization, and out-of-body experiences. These all-encompassing states are startling and uncomfortable for some.

It's mechanism of action is via multiple effects, including actions as a nonselective serotoninA monoamine neurotransmitter, biochemically derived from tryptophan, that is primarily found in the gastrointestinal (GI) tract, platelets, and central nervous system (CNS) of humans and animals. It is a well-known contributor to feelings of well-being. reuptake inhibitor and a sigma-1 receptor agonistA substance that initiates a physiological response when combined with a receptor.. DXM and it's major metabolite, dextrorphan, also act as an NMDAN-methyl-D-aspartate receptor. NMDA antagonists are often dissociatives. receptor antagonistA substance that interferes with or inhibits the physiological action of another. at high doses, which produces effects similar to, yet distinct from, the dissociative states created by other dissociative anaesthetics such as Ketamine and PCP.

DXM does not typically show up in normal drug tests however it can produce false positive results for PCP and/or Opioids in extended or specialized drug tests. Proper occasional use should not produce these false-positive results after a couple days have passed.


The racemic parent compound racemorphan was first described in a Swiss and US patent application from Hoffmann-La Roche in 1946 and 1947, respectively; a patent was granted in 1950. A resolution of the two isomers of racemorphan with tartaric acid was published in 1952, and DXM was successfully tested in 1954 as part of US Navy and CIA-funded research on nonaddictive substitutes for codeine.

The FDA approved DXM in 1958 after research supported its legitimacy and effectiveness as a cough suppressant. After its approval, it was introduced as an OTC medication under the name Romilar, which was introduced as a replacement for codeine containing cough remedies in an effort to cut down on abuse. In early 1960s Beat poets Allen Ginsberg and Peter Orlovsky, musicians such as Daevid Allen Soft Machine, and alternative authors such as Jack Kerouac known to have used DXM in the form of Romilar. In 1973, Romilar was taken off the shelves after a burst in sales because of frequent misuse, and was replaced by cough syrup in an attempt to cut down on abuse. In 1975, the popularity and extensive abuse of DXM was recognized, and Romilar was removed from the OTC market. However, DXM was specifically excluded from the Controlled Substances Act (CSA) of 1970, therefore, it was still legal to produce and use.

A few years after its removal from OTC, companies began introducing refined DXM products (e.g., Robitussin, Vicks-44, Dextrotussion) that were designed to limit recreational use by creating an unpleasant taste if consumed in large quantities. Within a short time those same manufactures began to produce forms of DXM with "some appealing flavoring," which led at least one researcher to suggest that the cycle of recreational abuse may be repeated. In 1996, DXM HBr powder could be purchased in bulk from online retailers, allowing users to avoid consuming DXM in syrup preparations.

Different Forms

DXM is widely available in over-the-counter cough treatments which appear in different forms including gelcaps, lozenges and syrups. DXM is also less commonly found in a more pure form, either extracted or bought directly from a chemical manufacturer.

While there are some products available which contain only DXM as active medical ingredients it is common to find products which contain DXM but also contain enough of another active ingredient to pose a serious risk to the user's health.


The ideal source of DXM would be an extraction, but that requires time and a chemical procedure which most people are not equipped to do. It's not a complicated process however it does carry some risks in itself. There is a technique known as the 'Agent Lemon extraction'.

Gel Caps

DXM Gelcaps such as RobitussinDM Gelcaps or other no-name brand products containing only DXM encased in a gelcap are often the preferred source for DXM users. For most users gelcaps which contain only DXM produce a more clear headed high in lower doses. Most users experience fewer side effects from gelcaps than from syrup however some users report an upset stomach from the gelcaps, indicating that some users may have a sensitivity to the edible plastics used to make the gelcaps.


There are also sore-throat and cough medications containing DXM which exist in the form of a hard-candy like lozenge. These sometimes contain only DXM, however most brands of DXM lozenges also contain analgesics such as acetaminophen or benzocaine. Some brands such as Cordicin Cough and Cold (also known as CCC) have a variety of products, most of which contain other active ingredients such as antihistamines or CPM (Chlorpheniramine Maleate) and may have one or two products which contain only DXM.

WARNING: Cordicin Cough & Cold is one of the most commonly used sources of DXM, and also one of the most dangerous. Nearly every single CCC product contains other active ingredients such as CPM, which can cause severe and life-threatening symptoms including seizures, shortness of breath or troubled breathing, weakness, loss of consciousness, severe dryness of the mouth, nose or throat, bleeding from the skin, mouth, eyes, rectum and vagina, and possibly death.

As always when using lozenges always choose a product which only has DXM in it.


Cough syrup is the most common source for DXM users. While there are many brand name and no-name syrups which only contain DXM as an active ingredient there are many active and "inactive" ingredients commonly found in cough syrups which can cause negative effects ranging in severity. See Harm Reduction for more information.

Some say the high produced from syrup is mostly sedating. You may feel sluggish when using it to get high on DXM, possibly as a result of other ingredients found in syrup however because of the even dispersion of DXM throughout the syrup it is said to produce a more 'solid' trip.


Delsym is brand with many formulations which contain Dextromethorphan Polistrex.

This is an extended release form of DXM which produced a longer lasting trip with weaker effects. It is said to be very difficult to reach the third plateau using DXM which may be preferable for this reason to beginners or users who would prefer a longer and weaker trip.


The dosage below refers to an "average" 180lbs / 80kg person taking DXM HBR. Before dosing it's important to note a few things:

  • HBR and Polistirex doses vary significantly due to polistirex slow absorbsion rate (1mg of DXM polistirex is equivalent to about 6mg DXM HBR).
  • DXM doses are affected by weight. For more accurate dosage information, see the following resources:
  • For a graphical chart of the dosage ranges this chart is helpful.
  • For an easy calculator that does the math for you, this page can be helpful.

Before dosing, be sure to read the Plateaus section to know which level you want to dose for.

Plateau range dosage for a 80kg (180lb) person.
First 122-200mg
Second 200-600mg
Third 600-1200mg
Fourth 1200-1600mg
Risk of death 2.2g+


Oral HBR
Total 6-8 hours
Oral Polistirex
Total 8-12 hours


Redosing is not advised.

It's better to know how much you've taken at the start of the trip, rather than guestimate how much you're on as you keep dosing. The effects will start to come in waves and may not be pleasant. If you feel the need, it's recommended to take a high initial dose and a lower dose 1-2 hours in.


One should make sure there is only DXM in the product they are taking. Grapefruit juice can potentiate dxm due to intactions with cytochrome P450.[1]


The high is not for everyone; it is said to loosely follow the rule of thirds: one third hates it, one third doesn't care, and one third like it.


  • Euphoria, mood lift
  • Increased giggling and laughing
  • Dissociation of mind from body (positive when sought)
  • Creative dream-like experiences
  • Increased tactile sensation
  • Some users report empathy and forgiveness towards other people


  • Pupil dilation
  • Visual stop motion effect (flanging or strobing)
  • Visual and aural (auditory) hallucinations
  • Decreased sexual functioning (difficulty achieving orgasm)
  • Confusion, disorientation
  • Skin sensitivity, alters tactile (touch) and skin sensations
  • Robotic, zombie-like walking, "robo-walk"
  • Discoordination, reduced agility
  • Loss of appetite
  • Involuntary flexing of muscles
  • Feelings of merging with adjacent objects like a couch or bed (with higher doses)


  • Vomiting
  • Dizzyness
  • Body itching
  • Rash, red blotchy skin
  • Diarrhea
  • Fever
  • Tachycardia (racing, pounding heart)
  • Some users report feeling disconnected, isolated from others


Some users report hangover or depression that might last up to a few days.


The robo-walk feels like all of the muscles in your body are activated at once and while strange to the observer is not painful to the individual. You can still walk but detailed coordination such as running, jumping, or maneuvering around furniture becomes much harder if not impossible. However, when you you start getting the effects of robo-walk, you really wouldn't want to be moving around anyway. The best thing to do is get a good pair of headphones, turn off the lights, close your eyes and let your mind wander.


There are various 'stages' to DXM trips called plateaus. Traditionally, there are only four plateaus that someone should try to aim for. All of them share general feelings of dissociation, but the strength and effects of these feelings are more pronounced in the later two plateaus.

There are two plateaus are commonly associated with a mix of being high on THCTetrahydrocannabinol and drunk on alcohol. If you take a first or second plateau dose, it's totally possible to socialize. Lower plateau doses are relatively easy to hide compared to higher plateau doses and talking with others becomes a lot easier while under the influence of DXM. It would also be fun to chill in your room alone and do whatever you normally do for fun, but it's suggested to try something that will take up most of your attention but allow your mind to wander at the same time. Something like playing a casual video game, or drawing whatever comes to mind.

If you take a third or fourth plateau dose, it's recommend to trip alone or with a close friend, as it's not a social drug at this dose. The best way to enjoy it is to lay back and listen to music with your eyes closed.

Choosing your destination plateau will depend a lot on what other drugs you've done and how comfortable you are with your mind. People who have never tried any hallucinogen other than THCTetrahydrocannabinol should start at First, while everyone else could start at Second. It is not advised to start at the third or fourth unless you have extensive experience with other dissociatives.

First Plateau

The first plateau is the lightest in effect. It feels a bit 'off', and is often likened to something of a cross between the effects of MDA and Alcohol. First plateau is usually slightly stimulating.

Effects commonly experienced at the first plateau level

  • A shift in thinking perspective; things look and feel 'different'
  • Increased tactile sensation
  • Increased appreciation of music
  • Feeling heavy, sensation of increased body weight
  • Enhanced emotional response & sensitivity
  • Some dizziness or vertigo

First Plateau dose: 1-2mg/lb.

Second Plateau

This pleatau is a bit more intense. You may feel like your stoned and movement may become difficult. The second is supposed to be fun and disorienting. Music is awesome to listen to and you can walk outside and perhaps hallucinate a small-mild amount. You can socialize with friends and you could say you're slightly drunk.

Second Plateau dose: 2-5mg/lb.


Most people stop their DXM journey here, as the final two plateaus are not really 'fun' but 'enlightening'. We don't recommend crossing this threshold until you're ready to move on from games of the mind to exercises of the consciousness. Enjoy the 2nd plat as long as you can because it's more of a fun experience and there is no going back once you've been past it. "Once you see what's behind the curtain, you can't enjoy the show" so they say.

Third Plateau

Third plateau is a full on dissociative experience. You cannot ignore the feeling inside of you and at this point its no longer a social drug and should be done by yourself or with a sitter. The third plateau isn't 'party-mode' or even 'socialize-mode'. Its more like 'alone-and-tripping-mode'. This is most akin to a "k-hole" that people experience after taking large amounts of ketamine. A lot of dissociation happens at this level, and the internal thoughts can be quite interesting. Using CEV's, DXM users have been known to have extremely vivid, controllable hallucinations and out of body experiences.

Third Plateau dose: 5-7.5mg/lb.

Fourth Plateau

This is the deep meditative state. Few people enjoy going this far, as all you can really do (or want to do) is sit, listen to music, close your eyes, and become a god. You can create universes in your mind just by thinking of them.

Fourth Plateau dose: 7.5-10mg/lb.

Fifth Plateau

Increasing the dosage above forth plateau will lead to level that some people refer to as Sigma Plateau. Keep in mind that this is dangerous, and very unpleasant most of the time, so TripSit is discouraging it.

Harm Reduction

See Dissociative Harm Reduction for general information.

Dangerous Ingredients Commonly Used in DXM Products

Many products which contain DXM also contain other medication or otherwise non-medically-active ingredients that can cause serious harm in the doses found in DXM containing products. If a user intends to use an OTC cough medication in order to get high on DXM they almost always will have to consume a dangerous quantity of other dangerous ingredients if they are present in the medication. For this reason it is strongly recommended to find a source which contains /only/ DXM.

The following is a summary of other ingredients commonly found in DXM products.

  •  : Acetaminophen/Paracetamol/APAP is a painkiller commonly found in over the counter flu medication, and is used in many Tylenol and Panadol brand products.
Acetaminophen/paracetamol/APAP is hepatoxic in high doses. This means it will damage your liver if taken in high doses.
Your body can only process a certain amount of APAP at once before it the normal pathways become saturated.
Once the regular pathways used for metabolizing APAP have been saturated the remaining APAP gets broken down in the liver by an enzyme called
cytochrome P450. ::: When forced to break down APAP this enzyme produces toxic metabolites!

The effects of an acetaminophen overdose may not be apparent for up to sixteen hours after the user has ingested the APAP! This makes APAP overdose even more dangerous because of the chance that a user might take more or not take notice after thinking they are 'in the clear'.

Under no circumstances should anyone attempt to use any DXM product containing 'Paracetamol', also known as 'APAP' & 'Acetaminophen'!

  • Guaifenesin is an expectorant. It works by causing the lungs to produce more fluid, making it easier to cough up phlegm.
Guaifenesin is added to many OTC cough, cold and flu medications to help treat the 'stuffed up' feeling which often found in viruses and colds.
Guaifenesin overdoses cause severe nausea and vomiting in most users. Some users report being able to use products which contain some guaifensin and
other users report no negative effects from guaifenesin containing products.
It is strongly recommended to avoid products which contain Guaifenesin when using DXM!
  • Antihistamines such as Diphenhydramine are often found in sleep-aids, night-time formulations of cold medications and allergy medications.
Antihistamines are sometimes found with DXM in night or 'PM' versions of products, and should generally be avoided when using DXM. When taken in
high doses antihistamines can cause dizzyness, nausea, a strong dysphoria, paranoia, delirium and hallucinations. Many antihistamines, OTC or prescription
can also have a dangerous synergy with some of the effects produced by DXM.
  • Food Coloring & other "Inactive" Ingredients
Many DXM products contain dyes which can cause allergic reactions in some users. Usually these dyes are not harmful in low doses however in doses which may be
required for DXM's effects they can become problematic. Tartrazine (FD&C Yellow #5) is one of the most notable coloring ingredients to cause reactions.
Cough syrups usually contain one or more chemical used to make them taste sweet.
Glucose, sucrose, invert sugar, and fructose are commonly used sweetening agents. These sweeteners pose an obvious risk to people with blood sugar conditions
such as diabetes or hypoglycemia.
Thickening agents such as propylene glycol or polyethylene glycol are found in most cough syrups. These are not toxic but may cause an upset stomach
when consumed in large doses.


DXM has several potentially dangerous interactions with pharmaceutical and recreational drugs including some analgesics (painkillers), antihistamines, antidepressants and stimulants.

DXM has the potential to cause Serotonin Syndrome if mixed with other serotonergic drugs such as antidepressants, MAOIs, empathogens which affect serotoninA monoamine neurotransmitter, biochemically derived from tryptophan, that is primarily found in the gastrointestinal (GI) tract, platelets, and central nervous system (CNS) of humans and animals. It is a well-known contributor to feelings of well-being. release such as MDMA, MDA, Mephedrone, etc. SerotoninA monoamine neurotransmitter, biochemically derived from tryptophan, that is primarily found in the gastrointestinal (GI) tract, platelets, and central nervous system (CNS) of humans and animals. It is a well-known contributor to feelings of well-being. Syndrome causes discomfort, excitability, irritability, and can be deadly [2] if not treated.

Chemistry and Pharmacology


Dextromethorphan is the dextrorotartory enantiomerOne of two stereoisomers that are mirror images of each other that are non-superposable (not identical). Think of it like the left and right hand, which are identical aside from orientation. of levomethophan, which is the methyl ether of levophanol, both opioid analgesics.


Binding receptors
NMDAN-methyl-D-aspartate receptor. NMDA antagonists are often dissociatives. - 7253
SERT - 2015
NET - 110606
Sigma-1 - 23
Sigma-2 - 240


Following oral dosing, DXM is rapidly absorbed from the GI tract. Where it enters the bloodstream, and crosses the blood-brain barrier.

At therapeutic doses, DXM acts centrally (brain) as opposed to locally (Respiratory tract). It's rapidly absorbed from the GI tract into the active metabolite Dextrophan (DXO) in the liver by the cytochrome P450 enzyme CYP2D6.

Around one in 10 of the Caucasian population has little or no CYP2D6 enzyme activity, leading to long-lived high drug levels.




DXM timeline on Erowid




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