Diarrhea, rash; itching, nausea, vomiting, candidiasis, fatigue, malaise, headache, chest pain, flatulence, abdominal distension, glossitis, urine retention, dysuria, edema, facial swelling, erythema, chills, throat tightness, substernal pain, epistaxis & mucosal bleeding. Ampicillin: Gastritis, stomach pain, black hairy tongue, enterocolitis, & pseudomembranous colitis; elevated liver enzyme levels. Urticaria, erythema multiforme, & exfoliative dermatitis. Fall in Hb levels & hematocrit, & increased leukocyte count.