I keep hearing nightmares about whole head radiation therapy is it that bad for you for small cell lung cancer of the brain?

Its often therapy: Small cell lung cancer often recurs in the brain, radiation therapy before this occurs lowers the risk and improves survival.

Not too bad: Brain radiation is the best treatment available for sclc that has spread to the brain. There is some risk of memory issues, but studies have clearly shown that the risk from the cancer is much higher than risk of side effects from the radiation. Common side effects are fatigue, hair loss, and altered taste.

Life saving: There is a lot of fear about whole brain radiation, whether for treatment of mets or prevention (prophylactic cranial irradiation) which is largely unfounded. Temporary side effects are fatigue, hair loss, and skin redness. There is little risk of dementia contrary to popular belief. There is a small risk of short term memory effects. Not treating will guarantee severe problems from the tumor.