Is High Dosage Of Ativan Advisable For Severe Anxiety?

I have been taking venlafaxine 225mgsr for approx. 3 months having started on 37ml, then 75, 150 then to 225mg but over Christmas had major anxiety relapse and had to add 1mg of Ativan per day. after seeing
my psychiatrist last was advised to take a further 37.5mg I do not feel happy on this medication should I seek a second opinion or what? I have been on antidepresients for 13years I am now 65