tonsillitis/pharyngitis
"I was prescribed a 5 day Z-Pak to treat a Streptococcal pharyngitis infection.  After the second day, the medication reduced the swelling and throat pain, but began to cause stomach cramping and pain.  By the end of the third day the stomach pain was severe and Doctor recommended to discontinue use.  This is the only antibiotic I have used that has caused an allergic reaction."