A brain injury can be very taxing on the system, including the immune system. Have you tried the supplement regimen I recommend? You can find it in the thread " Vitamin supplements." It has helped me overcome even my pollen allergies.
I'll move it to the top.
Mark in Idaho
58 years old, retired due to disability, married 33 years, father of three, grandfather of four, Suffered a serious concussion at 10 years old (1965) stopped most driving after last concussion at 46 years old (2001), Post Concussion Syndrome/Multiple Concussion/Impact Syndrome with PTSD, immediate and short term visual and auditory memory problems, slowed processing speed, visual and auditory processing difficulties, insomnia, absence seizures, OCD, 14 concussions since first concussion at 8 years old, Taking paroxetine and gabapentin for 12 years. Added L-Tryptophan and reduced paroxetine by half 3/2013
"Be Still and Know That I am God" Psalm 46:10