I'm the caregiver for a head/neck cancer patient. His radiation ended 4 weeks ago and we thought progress would be better. He developed strep throat, which was treated by a strong dose of penicillin and then developed oral thrush. We have those behind us and he was beginning to rally and try to eat by mouth, but now he has the shakes and is extremely ill with chills. I don't know if this is just the fatige for all he has been through and is normal or not.