My Husband Is Suffering From Chronic RMSF. He Is Tired

My husband is suffering from chronic RMSF. He is tired all the time, achey, has lost weight and is having problems sleeping and all of this causing depression.
I read that large doses of Vitamin C and PABA and cats claw have helped people.
The doctors gave him an antibiotic and it worked well last year but when it returned this year the antibiotic did not seem to help at all.
He has been tested for several things and RMSF is the only thing showing up in his blood.
He/we are desperate to help him feel better.
is there any harm to trying the above things to see if it helps?