Zithromax Z-Pak Side Effects: this is the second time i have taken the zpack for bronchitis...f http://www.medications.com/effect/view/34439 this is the second time i have taken the zpack for bronchitis...first time no symptoms, this time however......i am having verrrrry dark brown/ red urine, diarrhea, headache, stomach cramping, and body sweats....i don't know if this is due to my illness or I had similar reactions and thought I was having a heart attack! Thu, 01 Jan 2009 07:41:13 -0500 http://www.medications.com/effect/view/34439?item=15636 I had similar reactions and thought I was having a heart attack! http://www.medications.com/effect/view/34439?item=15636