Translation from French to English can be tough, so don’t get hung up on the words you are using right now. Just remember, to be respectful when describing your child, always say person first.
I also have adopted 6 children with ADHD. Adoption brings a lot of baggage with it. Everyone, including your child, hears all the wonderful stories about “not growing in your tummy but in your heart”. And that is all and good, but every adoption story has a dark side. At age 13, he may be going through some developmental good searches in his mind for his birth family and looking at how he fits into your family. An adoption therapist may help with those issues.
What information did you get from the adoption agency? Was there sexual abuse or severe abuse? These can all play into a child who is feeling out of control. Many times children come through adoption for abuse and neglect, but the underlining causes can very well be drugs and alcohol. All six of the children we adopted have diagnosis of Fetal Alcohol Spectrum Disorders (FASD). Of the three birth families we are dealing with, two of our birth moms also had diagnosis of FASD and one is suspected.
http://www.nofas-uk.org/ National Organization for Fetal Alcohol Syndrome-UK
France does not have a National Organization for FASD, but England does. Check out their website and see if your son fits the profile. ADHD is one of the co-occurring diagnosis and meds aren’t always helpful. Advocate for a correct diagnosis. Once you learn about how to parent someone with FASD, it will make things easier for everyone.