I found the best option for me was just sitting down and being open and honest. I finally just gathered up enough courage and told them.
I would tell them that I have ocd since a child. And that ocd is a mental disorder and I have that problem since I was a child and I didn’t know. Finally, I would tell them that one effective way to treat ocd is with medication. But be sure, and tell them that it has helped you. And it doesn’t matter through what you go though if in the end you are ok
I think you need to go in with the mindset that this is what is best for you and you are choosing to share the information with them but if they don’t agree with you it doesn’t matter.