Hey, to me the paranoia seems unrelated to the OCD. Generally, almost ALL OCD sufferers are aware of how irrational their thinking is. Based on your explanation, it seems he thinks his paranoia is rational/cautious thinking.
Im sure that since he is paranoid that that is why he doesnt trust mental health professionals, but this may cause a problem.
At this point i think you need to get him out of that room and into the "scary" world. Maybe dont jump into the deep end, but expose him to the things that he fears...little by little. Eat very healthy. Vitamins & supplements may be necessary.
S.E.E.
Sleep, Exercise, Eat Healthy
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