Hello there: my father has been on Aricept (half dose) for 6 weeks now and as the time is going on i would say he is deteriorating. He seems more vague and having more problems with concepts than before and seems to fall asleep all the time. Do you think this may be a side effect of the Aricept as it builds in the system or do you think it is the Alzheimer's deteriorating. Thank you in advance for any help or advice.