Welcome to Just answer !
Well you see almost all the anti depressants including effexor come with a warning before use that they may in rare users arouse suicidal ideas/thinking and even lead to suicidal attempts ( mostly inpulsive in nature ), irrespective of whether he /she is suffering from an underlying brain trauma.
So yes efffexor too can be linked to impulsive suicidal attempts , which is rare but possible , however brain injury has no established role or link in this, not yet.
And in such a case scenario i will suggest that the person shall be brought off effexor , which in fact being given at a very high dose , another reason which may proppelled the person to suicidal attempt and this effexor shall be replaced by another anti depressant like remeron or wellbutrin.
I am mentioning below a link , kindly go through it as it will enlighten you more about the link between effexor and suicidal ideas and attempts , albiet in rare cases.
Lastly i will conclude by saying that the possibility of the link between effexor and suicidal ideation should not be taken lightly and so should be brought to light in front of the treating doctor so that he /she can make the necessary changes in the drug regime by looking and ruling out or in this possibility.
I hope this helps..
Wish you all the best.
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