Im on 150 mg of venafaxine if i increase dosage above this i cannot sleep.i have been told chromium supplements would help me?

Chromium for sleep?: First, I am not aware that chromium supplements do anything for sleep. Second, i hope your venlafaxine is xr, if not then that could be part of the problem. Third, please talk to your doctor( a psychiatrist, i hope) about either changing your venlafaxine if that's necessary or adding something appropriate and effective for sleep. Somehow it doesn't sound like your doctor is hearing what you need.