Yes, you may include it.
This, from IRS Publication 502:
Lifetime Care—Advance Payments
You can include in medical expenses a part of a life-care fee or “founder's fee” you pay either monthly or as a lump sum under an agreement with a retirement home. The part of the payment you include is the amount properly allocable to medical care. The agreement must require that you pay a specific fee as a condition for the home's promise to provide lifetime care that includes medical care. You can use a statement from the retirement home to prove the amount properly allocable to medical care. The statement must be based either on the home's prior experience or on information from a comparable home.
