why are some like us sensitive and can't tolerate the meds, yet many others seem to be ok with them?
It has to do primarily with the speed at which our bodies metabolize the drug. (This does not correlate with digestive metabolism).
From the
Merck Manual , section covering pharmacokinetics:
. Drug metabolism rates vary among patients. Some patients metabolize a drug so rapidly that therapeutically effective blood and tissue concentrations are not reached; in others, metabolism may be so slow that usual doses have toxic effects. Individual drug metabolism rates are influenced by genetic factors, coexisting disorders,... and drug interactions.
There is some progress being made. By isolating the specific enzymes that are primarily required in order to metabolize various drugs (including the spectrum of psychoactive meds: antidepressants, anti-psychotics, mood stabilizers, etc), and then testing for the presence/absence and functionality of these enzymes in an individual, they can do a slightly better job of matching a person to a drug...or, more specifically, matching your liver to a drug.
It sounds like you may be a poor metabolizer,
@C j - meaning, there's something in your enzymes that causes you to build up too much of the drug's bioavailability, which will essentially give you the beginnings of an overdose. All the symptoms you describe are quite consistent with SSRI overdose.
That doesn't mean there are no drugs you can take.
Effexor is an SNRI. I'm going to guess you've also tried some form of an SSRI. Have you tried atypicals or mood stabilizers or MAOIs? If you aren't certain, feel free to just list everything (if you are comfortable). It's also pretty easy to google.
The genetic testing that reveals info about your enzymes is something you might investigate before you try another drug. Slowly, the medical community is getting educated. It's kind of unfortunate, because these tests benefit
anyone who is on
any medication - but the majority of doctors (in the US at least) say they are uncomfortable using it because they do not know how to interpret the results properly. I'm not sure of the position on it in the U.K.