Tea Tree Oil Roll-on
 
Tea Tree Oil is said to be very beneficial for the reduciton of allergy symptoms, and fever.  I have, personally, used it for both and had very good results. 
Tea Tree oil, or Melaleuca, is said to be an antiseptic.  It is has been extensively studied and there are clinical trials that prove it's effectiveness.  
Here is a link to all of the benefits of Tea Tree Oil, from Dr. Axe.