The only thing I can tell you is that if you stick with the bitters, you’ll probably become more accustomed to them as you continue. In the beginning I had to follow the bitters with a lot of water immediately (which is a good thing anyway), but after a while I didn’t seem to mind the taste at all. If it bothers you to place them on the back of the tongue, you can try dropping it on the middle or even front part of the tongue. Also if it helps, you can take a bite of something immediately after having the bitters. Yogurt seems to work well for this.