After I can consent to my own care, do I have to agree before my ADHD medical information is released to parents in Ontario?

If you are capable of consenting to your own care in Ontario, ADHD medical information is generally not released to parents unless you agree, with the details coming from PHIPA rather than from a single age of consent for treatment. The Health Care Consent Act is capacity-based and has no fixed age for treatment consent. For records, PHIPA says a capable person consents to collection, use, and disclosure of personal health information. If you are under 16, a parent may also be able to consent to information practices in some situations, but if you are capable and your wishes conflict, your decision prevails. If you are 16 or older and capable, you consent yourself. Rules, coverage and referral pathways vary by province and can change; confirm the current position with the relevant institution or provincial program. References: https://www.ontario.ca/page/what-ohip-covers

This is only my experience after I started consenting to my own care in Ontario, not legal advice. I told the clinic not to release my ADHD notes to my parents. They had me sign a disclosure preference. Later a parent portal still showed appointment dates until I asked them to turn off family access. I am not saying every office handles portals the same way.