There are two main types of medication currently used to treat Alzheimer's disease, known as cholinesterase inhibitors and NMDA receptor antagonists.
Cholinesterase inhibitors include Aricept, Exelon and Reminyl.
The NMDA receptor antagonist is Ebixa.
There are no drug treatments available that can provide a cure for Alzheimer's disease.
More top news
The social network faced fury after it barred a feminist group's image for an event promoting body diversity and acceptance.
Barack Obama left the owner of a streetside restaurant in Vietnam "stunned" when he stopped off there for a $6 meal.
Harriet Harman has defended Kim Kardashian posting naked selfies online, describing the Kardashian women as "brave and pioneering".