We had the same problem with the zantac with Hailey. It really tastes pretty nasty.
Zantac comes in another from called the efferdose, which is a little dissolvable pill. You dissolve it in water and then use a syringe to administer it and I’ve heard it tastes much better- citrus flavoured, I believe. Another option I’ve heard of is to add a bit of mylanta to the zantac. You can also get it flavoured at your pharmacy, but it ends up tasting like minty-grape I’ve heard.
Pepcid is another H2 blocker just like zantac, except it apparently tastes really good. I’ve heard it’s more expensive though.
Good luck.