Husband snorting Ritalin


I am posting here because I don't know what else to do and I have no one to talk to about this (who will understand what ADHD is). My 43 year old husband was diagnosed with ADHD (predominately inattentive and distracted) about 2 years ago. He has been taking Ritalin for 6 months. I caught him snorting his Ritalin yesterday - 10am on a sunny Sunday morning. He was in the garage and our two children were nearby in the house. He said he did it "for it to work faster" than taking it orally. I don't know what to do. Is this normal? It looked disturbing to me, and I am so confused and upset. 

Thank you