I Will Be Starting Flomax (spelling) This Week And Take

I will be starting Flomax (spelling) this week and take no rx's. I do suffer from heartburn but take a supplement that is working for me. I formerly took omeprazole but was able to stop when I happened on this supp. At any rate I notice that there are a number of caveats regarding heartburn and the medicine, I am 80 yrs young and in very good health. Any advice re heartburn possibility and the drug? Thank you