Palatability of oral antibiotic suspensions is important and may be a substantial factor in determining compliance in young pediatric patients. Because no comparative systematic data are available, we undertook the present study to assess the acceptance of and compliance with oral antibiotic suspensions commonly used in Israel. During a 4-month period lists of children receiving oral antibiotic suspensions were obtained from 3 major pediatric clinics, and parents were contacted by telephone 10 to 14 days after initiation of therapy, at which time information on age, sex, main disease, prescribed drugs and duration of treatment was obtained. Information regarding acceptance, side effects and compliance was obtained from 11 questions with graded scores. In the study 546 children received one of the following drugs: amoxicillin (n = 222); cefaclor (n - 142); cefuroxime axetil (n = 107); trimethoprim/sulfamethoxazole (n = 75). No major differences in background data were noted; more than 50% of each group had acute otitis media. Seventy-three percent of the cefaclor group reported acceptance of the drug with "pleasure" or "without problems" vs. 60, 55 and 20% for amoxicillin, trimethoprim/sulfamethoxazole and cefuroxime axetil, respectively, whereas "resentment" or "refusal" was reported in 11, 16, 26 and 56%, respectively (P < 0.0001). Mothers reported to be generally "satisfied" or "extremely satisfied" with the drug in 89, 81, 74 and 67% with cefaclor, amoxicillin, trimethoprim/sulfamethoxazole and cefuroxime axetil, respectively, and 85, 77, 73 and 67% of the children, respectively, received the drug for the entire prescribed course (P < 0.001). Our data demonstrate that marked variations exist in acceptance and compliance of oral antibiotic suspensions with children.(ABSTRACT TRUNCATED AT 250 WORDS)