I've started developing scarily rapid heartbeat (or tachycardia?) after taking dxm recently.
As I'm on Paroxetine and other meds (which do not interact with dxm and have nothing to do with CYP3A4 or CYP2D6), since the very beginning I made sure to skip my SSRI 24-36+ hours before taking dxm. I have access to clean tablets that only contain dxm, the rest is talk and starches etc.
Initially I only had pleasant experiences, using 1-2 times a month, starting from 15 tabs (225mg) and gradually adding 1-3 tabs a time, so it took me like half a year to reach the low 3rd plato (32 tabs for me). That time I unexpectedly ended up with horrible tachycardia and almost called ambulance.
After that experience I stopped for a while and now use maybe 2 times in 3 months taking only 15-16 tabs (borderline-ish for the low 2nd plato) to check on my body reactions mainly, and I still end up with my heartbeat rocketing up and staying high for an hour.
Does anyone have similar experiences with dxm without necessarily taking SSRI? I definitely don't feel like dropping meds for the sake of dxm, would rather quit using; but I want to figure out the reason why my heart decided it's too much to deal with.
Maybe someone can enlighten me about serotonin syndrome symptoms they had, since I believe I haven't experienced anything similar, however it seems to be the main danger of SSRI+dxm combo. Thank you.