Hi Tab Venizep 50 contain Desvenlafaxine 50mg  and Clonazepam 0.5 mg, yes it can cause these Symptoms. Clonazepam can cause the lazyness as it is sedative drug. Sometimes Desvenlafaxine causes muscle twitching or rigidity but usually these are self limiting in few days, if the symptoms persist or increase then consult your psychiatrist. Hope this helps you. Thanks and regards

I am guessing venizep has venlaflaxin in it. Usually it doesn't cause much discomfort however if it's causing it wil go away on it's own in a week or so. Drink lots of water and you shud be fine. If the problem persist then visit your psychiatrist again and tell him the issue.