Doctor, My dad is suffering from Alzheimer's Disease and he had been prescribed Hydergine. However it seems that the drug is no loner available in the market. Doctor, is the drug being marketed by the manufacturing company? Also, I want to understand the levels of efficacy of Hydergine vis-a-vis other drugs like Piracetam, mementine, rivastigmine and Donepezil. If it is efficacious, I may contact the manufacturer to send me the medicine. Also doctor what are the differerent dosage forms in which the drug is available because my dad is not able to swallow medicines. Also doctor please tell me if the foresaid drugs are more efficacious in the treatment in what manner they are more efficacious in terms of duration of treatment, therapeutic action and efficacy. My curiosity is higher relating to the Alzheimer's Disease because I am myself a medical student doing my MBBS. Thank you doctor