DXM SSRI/SNRI equivalent dosage comparing to typical SSRI/SNRI antidepressants

[Renald]

Anybody knows what is the DXM dosage as SSRI/SNRI if compared it to typical antidepressants (SSRI/SNRI)?
Also, is DXO SSRI/SNRI?

 

[dopamimetic]

The efficacy differs greatly between individuals and CYP2D6/3A4 activity, for me even 22mg DXM (30mg of the HBr salt) have significant serotonergic effects comparable to 75mg of venlafaxine but it's remarkably different in that I feel the effects immediately or at least after 2-3 days with such a low dose, including mydriasis. This could be due to sigma-1 agonism, but I suspect that it is either an "atypical releaser/inverse agonist" like it's been suggested for methylphenidate, working independent of the usually limiting auto receptors, or has to directly agonize some 5-HT receptors / antagonize auto receptors.

The numbers suggest that it's 10 times less potent at NET (23 and 240 nM) but somehow it feels more like 2 times. Maybe cause of the metabolite DXO which has no serotonergic activity but is a NRI with unknown but probably strong affinity, caused repeatedly severe panic with trip doses especially after the initial effects began to fade.
Besides of that, which renders it quite useless for me unfortunately (and makes it dangerous to combine with stimulants), it's an effective antidepressant. Was stronger for me than venlafaxine, paroxetine, mirtazapine and citalopram.

Obviously it can also cause the characteristic SSRI discontinuation syndrome, be prepared to taper down with a liquid formula or by opening the capsules. Although compared to the efficacy other SSRIs are worse.