What are the side effects and risks of chronic DXM use?
Prolonged, regular use of DXM has some definite risks. The most common is mania; this has been reported in people who used large amounts of DXM (especially to self-medicate depression) (1-3). Some research has linked sigma receptors to schizophrenia (46-49), and chronic use of NMDA antagonists has been shown to upregulate (increase) dopamine receptors (50). This could theoretically mean that DXM could trigger schizophrenia in susceptible individuals, although nobody knows for sure. DXM could also decrease immune function due to sigma activity (51). One thing that is known is that neither DXM nor PCP nor ketamine cause any change in PCP or sigma receptors. Another possible effect of long-term DXM use is neurotoxicity. This has not been observed, but would be consistent with DXM’s hypothesized ability to induce 5HT and dopamine release (52). Such neurotoxicity would probably be restricted to 5HT (serotonin) neurons, and be similar to the neurotoxicity resulting from use of MDMA (ecstasy)
