Thank you for posting this. It prompted me to do some digging, and indeed Ontario has revised the guidance a bit for third doses for the immunocopromised, to make ti easier. The new recommendations are here:
https://health.gov.on.ca/en/pro/pro...VID-19_vaccine_third_dose_recommendations.pdf They include "Table 1" which lists the qualifying medications by name [instead of just type, which is what they were listed as before]. And now patients who are on one of those medications apparently don't need a letter from their doctor, they should be able to bring the prescription / medication package with Rx label with them to the vaccine centre to get the third dose. Good new from me as I do not yet have the letter from my MD, but I certainly have a copy of my Rx and lots of the labeled medication packages

I will be off to the pharmacy this weekend for dose 3. So, THANK YOU !!!!