Harrison G A, Rubin M P, Davies R M, Speller D C
J Antimicrob Chemother. 1985 Apr;15(4):501-3. doi: 10.1093/jac/15.4.501.
Ten healthy volunteers received 3 g amoxycillin each week for up to four weeks. One volunteer carried streptococci resistant to amoxycillin in small numbers before the first dose was administered. After one administration of amoxycillin, this volunteer and one other yielded streptococci resistant to 1 mg/l amoxycillin on direct culture of dental plaque; after two administrations, resistant streptococci were detected in one further volunteer; and a total of six volunteers yielded resistant streptococci after the fourth week of amoxycillin administration. Repeated use of the single-dose prophylactic regimen encourages the emergence of streptococci considerably more resistant to amoxycillin than those generally encountered in the oral cavity, but the clinical significance of these results is uncertain as the peak serum concentrations of amoxycillin achieved after a 3 g oral dose for prophylaxis exceed the minimum bactericidal concentrations of amoxycillin for these strains.
十名健康志愿者每周接受3克阿莫西林治疗，为期四周。一名志愿者在首次给药前携带少量对阿莫西林耐药的链球菌。服用一次阿莫西林后，该志愿者和另一名志愿者的牙菌斑直接培养物中出现了对1毫克/升阿莫西林耐药的链球菌；服用两次后，又有一名志愿者检测出耐药链球菌；在阿莫西林给药第四周后，共有六名志愿者产生了耐药链球菌。重复使用单剂量预防方案会促使出现比口腔中通常遇到的链球菌对阿莫西林耐药性更强的链球菌，但由于口服3克预防剂量后达到的血清阿莫西林峰值浓度超过了这些菌株的阿莫西林最低杀菌浓度，这些结果的临床意义尚不确定。
