Or maybe you could try adding ginger, in quantity large enough to work as a medicine rather than just for taste. A cup of ginger tea made from a cutting of root works best, but they sell the herb in capsule form. You can store the root in your freezer and just cut off pieces as needed. Chop it up a little - big pieces are easier to retrieve with your spoon - and pour water just off the boil over it. Maybe you might want to stir in honey, too. The capsules (ginger) might not be fast enough to keep the other pills down.

Anyway, it sounds like you are taking an entire handful of pills all at once. A lot of supplements like the fish oil tend to be really big capsules. Are you taking all of these on an empty stomach, or do you normally eat a sufficient breakfast to pad your stomach a little? If you aren't taking the nutritional supplements with food they won't absorb as well anyway.