Dementia & disappearing arthritis pain

My aunt has had arthritis for years and took extra strength Tylenol in the mornings and evenings but also rubbed a numbing crème onto her knees. (She can’t take Advil or any kind of NSAID because her stomach bleeds if we’re not careful.)

Anyway, I believe she had some kind of mini stroke, followed by some dementia symptoms but she’s doing better now that she’s taking Namenda. Strange thing. After the dementia symptoms began and before she began Namenda, she never complained about arthritis and she walked fine. Is there something about Nameda that awakens “pain pathways” in the brain and could it have reactivated her ability to feel arthritis pain?