Hello ! I read your question and understand your concern. In my opinion he is suffering for hyipersomnia. It is more common in thalamic stroke. Unfortunately there is not a curable therapy to this problem. I would give some advises to try to regulate his sleep cycle: -Sleep a few hours longer at night to avoid excessive sleepiness during the day. -Exercise daily in the morning or early afternoon, if possible. -Engage in enjoyable activities that require your full attention, such as spending time with friends, writing letters, or playing with a pet. -Try to go to sleep and wake up at the same time every day. -Get out of bed and stay out of bed until bedtime. -Avoid foods that make you sleepy and heavy meals during the day. -Avoid alcohol and caffeine. I would also try Modafinil , which is a drug effective in primary hipersomnia. This drug must be prescribed under a neurologist prescription. Hope to have been helpful! Best wishes, Dr. Abaz Quka