Autism cycles or hormones?

21yr old son has autism and severe learning difficulties. Since about 16yrs there has been a progressive change leading into very challenging behaviour. Initially I put this down to puberty, teenage angst, emotional buildup with no outlet for relief(he does not masturbate).

Moving into adult services he was prescribed Risperidone and Depakote to combat antisocial behaviour in the community eg hitting, grabbing and spitting randomly at all types of people.In spite of meds behaviour continues to escalate, however a definite cyclical pattern has emerged.

About every 6 weeks he hits the cycle irrespective of environment, stimulus, who he is with or what he is doing.Only time lapsing, letting it run its course brings him out of it,this can take 2 weeks. In the meantime his whole demeanour changes; body posture, furtive eyes, increased repetitive traits, frequent toileting, making himself sick combined with the hitting out ,grabbing, spitting etc He appears to have no control, just an overriding compulsion to behave in this way.He will apologise and immediately repeat the action.You can see an internal struggle going on.

This situation is having a devastating effect on his access to the community and I worry that soon someone will report him for abusive behaviour with catastrophic knock on effects.

My gut feeling is it is raging hormones and that in time these extreme behaviour will balance out.

Please if anyone can relate to this I'd love to hear from you.