Gastrointestinal Distress

Common ADEs associated with antibacterial agents, but especially with macrolides, are nausea, vomiting, epigastric distress, and diarrhea.38,39,61,70,73 These symptoms may be amplified in patients on metronidazole with concurrent use of alcohol.70 When a patient has been taking an antibacterial agent for 1 to 2 days, diarrhea is probably due to the mild irritating action of the drug; however, bloody diarrhea with abdominal cramping is highly suggestive of pseudomembranous colitis, a superinfection with Clostridium difficile.117 Colitis has been reported with the use of nearly all antibacterial agents, but especially with clindamycin.38,39,61,70,73