Drug side effects 'mimic dementia': Common drugs used to treat depression, Parkinson's disease and allergies can produce side effects that can be mistaken for early dementia, scientists said today. They said doctors should be aware the drugs, known as anticholinergics, can cause confusion, memory loss and disorientation and question patients about medication they are taking before prescribing drugs for early dementia. "A large number of elderly people are taking medications that can mimic early dementia and are likely to be classed as having early dementia," Karen Ritchie, of the Hospital La Colombiere in Montpellier, France, said."