It doesn't give me heartburn, only nausea if dosage is too large.
What I do is take it after a meal or snack. I mix it with lemon juice that I squeeze drop by drop out of a halved lemon. I stay away from the acid they say to use, I found it too harsh for my system. Anyway, then I wait the three minutes and then add 2/3 Welches grape juice and 1/3 water. I immediately chase it with water to get rid of the gagging flavor. Then I immediately eat one sliced & peeled organic apple with peanut butter or preferrably raw almond butter. They say to eat two apples immediately after the dose but I find one apple with a nut butter really takes good care of any gag reflex or nausea.
Heartburn Remedy: When I was pregnant and had heartburn a few times (the only time in my life) my mom told me to mix plain yogurt with honey and some sliced strawberries. It worked like a charm. So you could take this immediately after the Miracle-Mineral-Supplement or even before.