DXM: an updated user's guide
July 22, 2017

dextromethorphan, or DXM for short, is an OTC (over-the-counter) antitussive drug commonly found in pharmacies in the United States (where the author is based). it also retains a degree of notoriety for its dissociative/psychedelic effects when taken in doses far exceeding what is recommended for a simple cough.

the story starts in the first half of the 20th century. codeine, an opiate, was once the gold standard in antitussive medication sold to Americans. however, for obvious reasons, abuse and addiction became a legitimate concern. thus, in the 1950s, the US government sought to find a non-narcotic replacement for codeine. dextromethorphan was chosen as this alternative. oddly enough, its molecular structure is the mirror image of levomethorphan, the codeine (O-methylated) ester of levorphanol, a very powerful synthetic opioid analgesic. despite the structural similarity to opiate drugs, its affinity and efficacy at mu-opioid receptors is negligible. the g-men had their candidate. what could go wrong?

maybe they didn't anticipate that former abusers of OTC codeine would attempt to abuse this new and exciting drug, first marketed in the early 1960s as Romilar in tablet form, in the hopes of achieving chemical nirvana. much to their surprise, the effects achieved were quite different from the blissful apathy of the opiate reverie. despite this setback, users took to this new high in sufficient frequency to prompt the Romilar brand manufacturer to pull the tablet formulation from the US market and replace it with the now-familiar cherry menthol-flavored cough syrup we know today, specifically designed to be anything but palatable, with excessive amounts of artificial sweeteners such as sorbitol to discourage further abuse. DXM became relegated to fringe use, most notably in the punk rock scene of the late 1970s, continuing into the 1980s. with the birth of the World Wide Web in the early 90s, prospecting users were able to disseminate and utilize information regarding DXM use/abuse, eventually culminating in William White's famous DXM FAQ, which, although outdated and in many ways inaccurate, serves its life today at Erowid. the 'dxm' subreddit is the 21st century version of this phenomenon.

this article will not deal with the question of why people like to get loaded on drugs. that is a philosophical discussion for another day. the purpose of this article is to provide readers with useful qualitative information, as well as the author's tried-and-tested method(s) of optimizing the DXM experience.

let's start with the plateau model. DXM can be divided into four main dose-dependent "plateaus" numbered 1 through 4, with each respective plateau/stage containing its own distinct subjective effects and each stage having a larger minimum dosage than the previous one. doses (in milligrams) are relative to the user's mass (in kilograms).

beginning with plateau 1, it can be achieved anywhere from 1.5-2.5mg/kg. a notable shift in consciousness may be noticed, best described as a "dirty" psychostimulant effect. increased alertness, greater appreciation of music, slight visual distortions not unlike alcohol, general euphoria, and an overall feeling of being "lightweight" can be experienced. plateau 2 follows immediately after at 2.5-7.5mg/kg, and this is where the experience becomes more like a psychedelic "trip". closed eye hallucinations are ready on-demand. euphoria is amplified. open eye visuals become more like being drunk, with the added effect of visual "flanging" as described by William White. it is much easier to ease into a dream-like state at this plateau. to summarise, this plateau is a stronger version of the previous one.

the next two plateaus, 3 and 4, are not for the faint of heart. only experienced users should consider this option. the 3rd plateau (7.5-15mg/kg) is where the real "dissociation" (which will be explained later) begins. poor motor coordination, confusion and memory loss, immersive dream-like experiences, extremely vivid closed-eye hallucinations, and auditory distortions and hallucinations are not uncommon. you can expect to lapse in and out of consciousness and not remember what you just saw on the other side. those who strike gold can expect telepathic contact with "superior" beings/entities, as well as vivid long-term memory recall, often reliving past experiences in one's (or someone else's) life. the 4th plateau (>15mg/kg) is where all connection to the external world is lost. expect to become catatonic while traveling through deep space.

"so, what's the big deal? can't i just take some LSD and trip? why do i have to chug cough syrup to have fun?"

the author is glad you asked. remember the term "dissociative" used earlier? it's really used to describe a unique class of hallucinogens which induce a state of "dissociative anesthesia" by antagonizing NMDA receptors (more on this later). this class of drugs also includes PCP, ketamine, nitrous oxide, and other research chemical analogs of the former two. dissociation is best described as separating your conscious awareness from the external environment. whereas with classical psychedelic drugs (CPDs) such as LSD and psilocybin, which mediate most of their effects via 5-HT2A (a subtype of serotonin receptor), increase connectivity, CNS stimulation, and awareness of reality, dissociatives such as DXM perform the opposite. instead of awareness of everything and the "oneness" of the universe resulting in "ego death", it induces an awareness of nothing, or a "zero state". it is a primarily internal experience of going deeper into oneself until it is realized that there is no "you". this is a different kind of "ego death" (the dissolution of one's sense of self-concern). states such as these can often lead to a feeling of spiritual "rebirth" and percieved enlightenment. dissociatives in particular are less likely than CPDs to induce panic attacks and other forms of emotional distress. rather, most of the negative effects thereof are physical. if one can muster through these obstacles, the reward is often greater, but at a greater long-term cost as they have a much more dubious safety profile than CPDs. DXM in particular is sufficiently distinct in subjective effects from ketamine and PCP, and is much more readily available (at least in the US), so our focus is restricted hereto.

what kind of negative effects can one expect? apart from the aforementioned loss of motor coordination and short-term memory, vomiting and nausea are intrinsic to the dissociative experience, especially with higher doses. once the middle 2nd plateau is reached, moving around is not recommended. this is a solitary and subdued experience. stay indoors for this one.

"ok, ok, cut to the chase: how do i use it properly?"

hey now, this is not a lighthearted matter. sufficient groundwork must be established in order to make the most of DXM's power. most people fail to take the necessary steps in preparation for this ritual and end up having a ridiculously bad time, almost akin to the acid casualties of the 60s, although not as numerous.

rambling aside, we have to establish DXM's pharmacological profile in order to really comprehend what it's doing and how to "do" it. DXM, being primarily a dissociative hallucinogen, is an uncompetitive NMDA (a type of glutamate receptor) antagonist.

for those unfamiliar with basic neurobiology, excitatory signals (action potentials, or APs) are sent along nerve cells (neurons) and continued along synapses between other neurons further down the network. glutamate is the chief excitatory neurotransmitter in the mammalian nervous system. "excitation" means you feel stimulated and awake and connected (GABA, on the other hand, is the yin to the yang of glutamate, inhibiting APs). when glutamate binds to a corresponding receptor, it opens the ion channel for positively-charged calcium and sodium ions to enter, thus depolarizing the cell and making it more likely to transmit an AP. DXM works by blocking this ion channel (in the case of NMDA receptors, it is for calcium ions only), much like magnesium. the result is a "calming" effect on the nervous system, followed by less neural activity and less overall connectivity between different regions of the brain. at high enough doses, entire regions can be cut off from each other, thus inducing true "dissociation". go read a textbook for more background information about how neurons work, because this isn't biology class.

continuing onward, DXM is also a dopamine and (non-selective) serotonin reputake inhibitor (latter more than the former). because of this, DXM is not to be taken with any antidepressants, MDMA/MDA, MAOIs (monoamine oxidase inhibitors), or any other drug which would induce an out-of-control synergistic reation with this aspect of DXM. doing so may result in serotonin syndrome, which can be fatal, if not extremely unpleasant. consult a doctor about any medications you are currently on and if they would contraindicate the use of DXM (for a cough, obviously).

aside from also antagonizing certain nicotinic acetylcholine receptors, the last major pharmacological property of DXM is its high affinity as a sigma-1 receptor agonist. not much is known about this receptor set, but it is thought that its activation contributes to DXM's psychotomimetic ("psychosis-like") effects.

"uh... dude, why are you telling me all this? what does this have to do with tripping sack?"

patience is a virtue, dearest reader. the reason this matters is because DXM, when taken orally (the only effective way for our purposes), is actually two drugs, not one. DXM's subjective effects rely entirely on its interaction with its main metabolite, dextrorphan (DXO). like morphine is to codeine, DXO is to DXM when the methoxy (H3C-O) group at position 3 in the molecule is removed in favor of an alcohol (OH) group. since it is taken orally, it is primarily metabolized by the CYP2D6 enzyme group in the liver. in fact, many other drugs are metabolized by these enzymes, so it is important to not combine them with DXM in excessive amounts thus forcing them to compete for the metabolic process.

DXM itself is a weak NMDA receptor antagonist. DXO is nearly ten times more potent than DXM in that regard. the main idea here is that the interaction between these two compounds is what gives DXM its unique character as a hallucinogenic agent. if we can manipulate the metabolic rate of DXM such that we can control the amount of DXO that reaches our brain, then we can achieve optimal effects.

on this note, there is a 5th plateau, known as "plateau sigma". this is achieved by abusing the metabolism of DXM when taking 1st plateau doses every two to three hours. the result is a dramatically higher ratio of DXM to DXO, and thus much more saturated binding at sigma-1 and sigma-2 receptors. users can expect to experience an extremely long and uncomfortable waking psychotic state. the author emphasizes utmost caution and discretion when considering this route. it is simulated insanity.

"are you done yet? please tell me how to expand my consciousness."

thanks for sticking by thus far. we're ready to dive into the author's perfected procedure of achieving the optimal visit to the dextroverse...

... right after we establish more groundwork.

which brand of DXM should you get? the author recommends (generic or Robitussin-brand) Long-Acting Tussin. this is the syrup formulation. gelcaps are also available in brand and generic packages, but syrup is (for the author) easier to consume and digest. when reading packages at the pharmacy (CVS, Walgreens, etc) or supermarket, pay attention to the active ingredients. the only one listed should be dextromethorphan hydrobromide (HBr). most formulations contain a combination of DXM with guaifenisin (an expectorant, will cause much more vomiting), phenylephrine (a psychostimulant and decongestant), and/or acetaminophen (also known as paracetamol, an anti-inflammatory analgesic which has no CNS activity but can damage the liver in excessive doses). the only quantity the author can find at any store is the 4oz bottles; 8oz bottles were more common back in the day but have since disappeared entirely from the shelves. generally, each 4oz bottle contains 15mg/mL of DXM, which equates to 354mg of dextromethorphan HBr. the author does not recommend consuming Delsym, as it is an extended-release formulation and will result in an unnecessarily long trip with a much different character of effect that will not be discussed here. don't like the advice? then please tell us all why are you still reading.

additionally, an antihistamine such as chlorpheniramine maleate or diphenhydramine hydrochloride (HCl) is recommended in order to mitigate DXM's many side effects including nausea and itching (not previously mentioned). additionally, these medications also compete for the same liver enzymes as DXM, so a small dose will affect DXM's metabolism and therefore the character of the experience.

as far as other drugs go, in combination with DXM, avoid psychostimulants such as cocaine and amphetamine. these can induce hypertension and possibly cardiac arrest. this is highly unsafe to attempt. depressants such as alcohol and benzodiazepines should only be used before or after the peak effects have occurred, and in drastically reduced dosages relative to the DXM dosage that has been chosen. DXM can and will amplify this depressant effect and may result in fatal respiratory depression, if not incredible bouts of vomiting. opioids and opiates should also be avioided not only for this same reason, but also because they will ruin your life and you should stop and get help (like, now). on a side note, NMDA antagonists have been shown to enhance opioid analgesia while attenuating the development of tolerance due to reduced long-term potentiation (LTP), and can be useful if you have a legitimate use for pain medication, but that's another story for another day. smoking tobacco cigarettes will greatly intensify the effects of DXM, most of the time in a very pleasant way, but sometimes in a very unpleasant way. use caution.

CPDs such as LSD and psilocybin synergize in a very unique and spectacular way with DXM. expect visual size distortions, enhanced fractal patterning, even brighter colors with added chromatic aberrations, and more. you can visit many places with this combination, but it is only for experienced psychonauts, as the effects can be quite intense (although not life-threatening), especially for the uninitiated. perhaps the best synergizer of all with DXM would be, of course, cannabis (marijuana, for you yokels). more information on this shortly.

okay, we're ready to begin.

"fucking finally, i was about to ditch this bullshit rambling nonsense."

right. start by not eating for 6 hours. continue by taking either 4mg of chlorpheniramine maleate or 25-50mg of diphenhydramine HCl. wait 30-60 minutes. get your bottle(s) of DXM and slam it/them. if you focus your mind away from the horrid taste of the syrup (as well as pinching your nose), you can get it down with ease. feel free to chase it with a strong liquid such as lemon juice (alcohol in small amounts is okay). wait 1-2 hours. while the DXM takes effect, find a room with a bed that you will not leave. lay down. get yourself ready. turn off all the lights. turn off any electronics you won't be using (this includes your phone; at least put it on airplane mode). put together a fitting playlist of music (this is extremely important; music greatly enhances the experience, so make sure it will fit the mood).

after a while you will start to feel weird and uneasy. nausea is very common and the author recommends to vomit before the peak is reached (roughly 2 hours after dosing). this will be very unpleasant and sometimes it will be painful, but after getting this over with, you will feel as if you have purged something from your being. a catharsis, if you will.

start playing the music you selected, and prepare some cannabis to be smoked. once you feel as if you have reached the peak (you will know), take a toke. you don't need that much, but since DXM is a cough suppressant you will be able to take monster rips without expelling your entire respiratory system. however, if you are taking any CPDs in combination with DXM, then take those first, preferrably immediately after vomiting and before the peak. wait for it to reach initial effects, then proceed with smoking the cannabis. this is important in order to reach a perfect trifecta of "peaking" on all three drugs at the same time, resulting in a spiritual orgasm of sorts.

assuming you chose a pitch dark room with good music, you will notice that DXM's visuals are greatly enhanced by the cannabis, and there is some degree of control when it comes to closed-eye hallucinations. to make things better, cannabis will lessen many of the uncomfortable physical effects of DXM, almost like an insulating blanket. virtually every aspect of the experience is enhanced. the author has reached unspeakable and divine states of awareness and lucidity using this exact method. your mileage may vary.

since this part of the trip is highly subjective, the author will not go into any further detail, as it is your experience, and it is your responsibility to take back what you can from it. once the experience begins to die down, you will notice a certain restlessness from the lingering effects of the DXM. valerian root and/or a small dose of a benzodiazepine may help in initiating sleep. again, your mileage may vary. over time, the author has noticed that this effect, as well as other negative effects, can increase in frequency, while positive effects diminish. this is tolerance. again, your mileage may vary. the author makes no guarantees of anything and is not responsible for any decisions the reader may act upon.

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