I'm sure you suspect that Tylenol or Excedrin are not OK, so I'll tell you they aren't. They only mask symptoms and they clog up 'yer innards.
However, I know how bad a cleansing headache can be. Just last week I missed 2 days of work for headaches leading to vomiting.
I do have some new ways of dealing with them. You might not like them:
1. ENEMA! Yes, enema, gets things moving and often the headache is mysteriously gone. If you don't want to do it yourself, you can go (even better) and have a colonic
2. drink a ton of water. Lemon in the water helps a bit. Try to eat only a little, drink a lot.
3. stand on my head, go for a walk, sweat a bit.
4. got a nice thing from the health food store called "Migrastick". It is a mixture of oils with a roller ball. Roll it on your temples, back of your neck. It smells wonderful and does help.
The headaches will go soon. Try to avoid the headache remedies if you can. If you can't, well, keep cleansing and hopefully you won't need them at all soon.