My son has been diagnosed with pdd, ocd, and adhd. i was going to cut his hair and noticed he has grey hair. is this normal?

PDD is no longer: a valid diagnosis. The DSM-V's sole diagnosis of Autistic Spectrum Disorder defines Levels 1, 2 & 3 by function & need for services. 40-70% of kids with ASD also have ADHD & almost all have anxiety disorders. Is his IQ 70 or < or is it > 70? Has he had a Chromosomal Microarray, DNA Probe for Fragile X & an audiogram? A few genetic syndromes have streaks of gray hair or premature graying.

Premature Greying: Going gray, by itself, does not mean you have a medical problem, except in rare cases. Scientists don’t know exactly why some people go gray early, but genes play a large role. Also, a vitamin B-12 deficiency or problems with your pituitary or thyroid gland can cause premature graying that’s reversible if the problem is corrected. Recommend further eval by pediatrician.