<prompt> Drug of choice in drug induced parkinsonism isLevodopaBenzhexolSelegillineAmantadine  <response>: Benzhexol 421-KDT 6th Trihexyphenidyl Benzhexol is most commonly used drug in drug induced Parkinsonism Anticholinergics are the only drugs effective in drug phenothiazine induced parkinsonism Drug used in Alzheimers disease Acetylcholinesterase inhibitors - donepezil, galentamine, rivastigmine, tacrine NMDA receptor antagonists - Memantine 