In this review the drug trials on patients with dementia were covered in two seperate parts: Alzheimer's disease and other reasons. The drugs used or tried for the pathology underlying Alzheimer type senil dementia include a wide range of drugs such as, acethycholinesterase inhibitors, memantine, latrepirdine, antiinflammatory drugs, antioxidants, neuronal growth factors, amyloid-based therapeutics, agents interacting with neuronal microtubule, estrogen, rosiglitazone and the drugs against the factors supporting the pathology. Vascular dementia, Pick disease, neurologic disorders, head trauma, frontotemporal dementia, infectious diseases, metabolic diseases, alcoholic dementia and drug utilization are the reasons for dementia other than Alzheimer's disease. The drugs that are recommended to be used in these patients are acethycholinesterase inhibitors and memantine. Besides, some drug research has been done on the potentail beneficial affect of gingko biloba, statins and atipic antipsychotics in patients with dementia however the present evidence with these substances is not satisfactory. In this review, a summary of the research with these substances has been presented.