cefadroxil monohydrate /sē′fədrok″sil/ , a cephalosporin antibiotic. ▪ INDICATIONS: It is prescribed in the treatment of selected bacterial infections. ▪ CONTRAINDICATIONS: Known hypersensitivity to cephalosporins prohibits its use. It is administered with caution to patients with a history of allergy to penicillins. ▪ ADVERSE EFFECTS: Among the most serious adverse reactions are hypersensitivity reactions and severe diarrhea, nausea, and vomiting.