Use of Amoxicillin in the Treatment of Urinary Tract Infections

Abstract

Amoxicillin (α-amino-p-hydroxybenzylpenicillin), a new semisynthetic penicillin similar to ampicillin, was evaluated in 31 selected patients who experienced 32 episodes of urinary tract infection due to a variety of gram-negative bacilli and grampositive cocci. Amoxicillin was administered in doses of 250 mg every 6 hr or 500 mg every 8 hr, usually for 10–14 days. Clinical cure or improvement occurred in 27 of 32 infections (84%); eradication of the pathogen was demonstrated in 27 of 31 infections (87 %). Other than two allergic reactions, no significant toxicity was noted. The range of serum levels was wider than expected, although the mean was consistent with prior experience. Proteus mirabilis, Escherichia coli, and occasionally Enterobacter were more sensitive than Klebsiella or Serratia. Lancefield group B streptococci were exquisitely sensitive. Thus, amoxicillin appears to be useful and comparable to ampicillin in the therapy of urinary tract infections.