cefaclor /sē″fəklôr/ , a cephalosporin antibiotic. 
INDICATIONS: It is prescribed in the treatment of selected infections caused by susceptible strains of bacteria. CONTRAINDICATIONS: Known hypersensitivity to cephalosporins prohibits its use. It is used with caution in patients who are allergic to penicillin. ADVERSE EFFECTS: Among the most serious adverse reactions are hypersensitivity reactions and diarrhea, nausea, and vomiting.
