Suggest Treatment For Severe Depression And Hallucinations

hello , i have a very close friend that has been on a medicine that contains esomeprazole for a suspected ulcer for a month right now , recently he has been having severe depression , confusion , nervousness . i suggested that it could be from the medication because i went through such a period because of a local pain killer brand which then i discovered was the reason behind my hallucinations and depression . he usually takes 40 mg in the morning .today was the first day he stops it and has still not been feeling great . i just waned to know when will he stop experiencing such symptoms . how long does it usually take to feel completely normal again ?