Well i think taking any medical advice from ME or ANY gfy'er is a bad idea.
Your best doctor..is YOU. Become an expert in your own condition. Use your doctor to suppliment your knowlage, but dont trust him/her blindly.
Its widely known that taking APAP's ect will just make you feel worse over time..They will make your headache worse!
And if your liver is already taking a spanking, you need to look at your diet. SOme foods, i think (grapfruit is the classic one..) keep your liver busy/blocked and then its suddenly faced with a backlog of other junk to process. Booze does this too.
http://en.wikipedia.org/wiki/Naproxen
Risks and side effects don't look to nice..