Comparison of the clinical and bacteriological efficacy of clarithromycin and erythromycin in the treatment of streptococcal pharyngitis.

The efficacy and tolerability of clarithromycin and erythromycin stearate in the treatment of documented Group A beta-haemolytic streptococcal pharyngitis were compared in a single-centre, open, out-patient study. One hundred and twenty patients were randomly assigned to each treatment group. Dosage of clarithromycin and erythromycin was 250 mg twice daily and 500 mg twice daily, respectively; each patient was given a 10-day supply of medication. Clinical success (cured or improved) was observed in 111 (96.5%) of 115 and in 108 (93.9%) of 115 clinically-evaluable patients treated with clarithromycin and erythromycin, respectively. Eradication of the pathogen occurred in 108 (97.3%) of 111 and in 98 (92.5%) of 106 bacteriologically-evaluable clarithromycin and erythromycin patients, respectively. Adverse events reported by 7 (5.8%) of the clarithromycin-treated and by 12 (10%) of the erythromycin-treated patients included epigastritis and nausea and vomiting. In general, the severity of adverse events was greater for the patients treated with erythromycin, necessitating the discontinuation of therapy in 8 (6.7%) patients treated with erythromycin as opposed to 1 (0.8%) patient treated with clarithromycin. Although clarithromycin and erythromycin were comparable in terms of efficacy, clarithromycin was better tolerated.