Lower plateau doses of dextromethorphan are characterized by a mild intoxication and euphoria similar to a combination of MDA and alcohol, due to its serotonin and dopamine reuptake inhibition. Often, audio intake is altered, leaving the user with an altered peception of
music and sound. This alteration allows the brain to process sounds slower, making
music sound different, more defined and bold.
Music often adds to the pleasure of a DXM experience.
Moderate doses tend to decrease agility, coordination and affect the user's perception of
time. Some users report euphoria, while others do not. Sound
may take on a flanging effect and the user
may have difficulty distinguishing distances between objects. Dissociative cognitive effects become apparent, resulting in the user feeling "detached" or "disconnected" from reality. Closed eye hallucinations
may be observable.
High doses have been compared to ketamine and can include significant depersonalization and dissociation, bizarre thought patterns, and the user often feeling completely disconnected from external reality. Marked changes in visual perception are increasingly noticeable and can include lilliputian hallucinations. Coordination is significantly impaired, and many users are unable to move comfortably. Out of body experiences and religious experiences are common. Extending the duration of the DXM trip through pre-dosing (taking multiple "booster" doses throughout the day before the main dose)
may bring about a separation from reality which has much in common with forms of psychosis: extreme schizophrenic hallucinations, such as hearing voices, seeing entities with eyes open, and experiencing a total breakdown of reality. This state
may occur because the effects of DXM are caused by DXM itself and its metabolite, dextrorphan. When pre-dosing, the ratio of DXM to DXO (dextrorphan) can be changed due to DXM's effect to inhibit the liver enzyme that processes it. DXM is speculated to cause many of the strange thought processes of the experience, while DXO is suggested to be more physically intoxicating. So through increasing the amount of DXM, a completely different experience
may occur with the strange schizoprenic-like mindset. Dextromethorphan becomes
toxic at 20 - 30 mg per kg of bodyweight, producing vomiting, fever, and possibly death, and high doses
may be dangerous.
Neutral effects of using DXM include "robo-walk" ( when a user on DXM walks like a robot due to loss of coordination ), discoordination, trismus and bruxia (clenched jaw, teeth-grinding), and heavy pupil dilation. Negative effects can include
diarrhea, vomiting, and severe nausea due to the consistency of cough syrup, and are more prevalent when it is imbibed in an extremely short amount of
time. Using DXM can also cause hangovers on the following day, and is extremely dangerous when used in combination with alcohol. Excessive use over a long period of
time can have adverse effects on the liver, pancreas, and kidneys due to the extremely high concentration of glucose in cough syrup.
Some DXM mixtures have the active ingredient listed 'dextromethorphan polystirex' on the bottle. This means the DXM molecule with the hydrobromic acid base is suspended inside a plastic-molecule capsule which extends DXM's half-life to 10-12 hours. This half-life extenstion is because half of the DXM takes about 3 hours to break down due to being inside the polystirex. Because of this long metabolizing method, the blood stream receives a greater DXM to DXO ratio. Using Delsym often will create tolerance very quickly compared to just DXM products without the polystirex mixture.