Role of current Alzheimer's drugs

The Food and Drug Administration (FDA) has approved two types of drugs specifically to treat symptoms of Alzheimer's disease.

• Cholinesterase inhibitors
• Memantine

These drugs:

• Are approved for specific Alzheimer's stages. These stages — mild, moderate and severe — are based on scores on tests that assess memory, awareness of time and place, and thinking and reasoning.

  Doctors might, however, prescribe Alzheimer's drugs for stages other than those for which the FDA has approved them. Alzheimer's stages aren't exact, individual responses to drugs vary and treatment options are limited.

  If your doctor prescribes medication as part of your Alzheimer's care plan, make sure you understand the drug's potential benefits and risks for your situation.

• Are not approved for mild cognitive impairment (MCI). This condition, which involves subtle changes in memory and thinking, can be a transitional stage between normal age-related memory changes and Alzheimer's disease. Many people with MCI — but not all — eventually develop Alzheimer's or another dementia.

  Clinical trials testing whether Alzheimer's drugs might prevent progression of MCI to Alzheimer's have generally shown no lasting benefit.