Hi Cendrine,
My heart and prayers go to you both! : )
My personal opinion is that the trust and communication he has with you as a parent is the best thing he as going for him at this point.
The National Association for Holistic Aromatherapy has this article to offer:
Also, you could diffuse
Cedarwood Atlas or
Nutmeg, or dilute either at 3% and apply as desired (some have mentioned that applying to the heart and chest area is effective).
Master is another one to consider for male hormonal balance.
I hope this helps.
Blessings, Linda