Anybody allergic to Tylenol?

I am allergic to Tylenol and just wondering if anybody else on the board is too.  If you are, what did you take while you were pregnant for headaches and such?  I had a horrible headache today and had to take off of work b/c I didn't know of anything I can take.  I will see my MD on Wed, but just wondered if any of you had this problem.