I was researching children's medications on the internet the other day because my nephew spits out his medicine too...
You could try ElixSure, which is the new medicine they show on TV where it's like a gel so that it doesn't spill when you give it to your child. However I understand that it liquifies again once in the mouth, so you might still get spit at. There are formulas for fever/pain, congestion, and cough.
http://www.elixsure.com
There is also a great article that I found that might help:
http://www.washingtonpost.com/ac2/wp...nguage=printer
In that article, it mentions "FLAVORx" which is available at many pharmacy chains. There are up to 30 flavors that can be added to childrens' liquid prescription medications, and some pharmacies may even make non-prescription meds for you. For some of the worst medications, they can add something to decrease the bitterness as well. You might want to ask about it at your pharmacy. The article says they even have suckers for your kids to try, to see if they'll like a specific flavor.
GOOD LUCK!!!
Oh, and I work NICU, so I understand your worries about dealing with parents. When I first started, I was so nervous about it because I'm not a parent and couldn't put myself in their place, but it got better. I think that, as a parent, you have more compassion and can understand a little better what they're going through. You'll be fine. Just provide support and answer their questions. Helping the parents is often one of the most satisfying parts of working with children.