Pros and cons on breastfeeding

I’m 21 weeks and I know I only got about a few months left until I have my baby. I have been debating on breastfeeding. My sister does it and I see the benefits of it, but I was also on a lot of medication before I got pregnant and I know I will need my medication once I have him. I have lots of GI issues, migraines, mental health problems. Right now I have been good but I know I’ll need some of the medication afterwards and that’s what somewhat is stopping me from breastfeeding because I want to make sure he is safe and okay. Anybody have opinions or advice about the pros and cons ?