Controlled study of the efficacy of clavulanic acid-potentiated amoxycillin in the treatment of Chlamydia psittaci in cats

Twenty-four specific pathogen-free cats were inoculated with 3 x 10(3) infe ctious units of a field isolate of Chlamydia psittaci on to the corneal sur face. Seven days later they were assigned randomly to three groups of eight and treated orally for 19 days with either clavulanic acid-potentiated amo xycillin, doxycycline or a placebo. Both treated groups responded rapidly, with a marked reduction in isolation rates and clinical scores which were s ignificantly lower than in the placebo group within two and four days, resp ectively. After two days the group treated with potentiated amoxycillin had a significantly lower isolation score than the group treated with doxycycl ine. Forty days after they were infected the clinical signs recurred in fiv e of the eight cats treated with potentiated amoxycillin, but a four-week c ourse of potentiated amoxycillin resulted in a complete clinical recovery w ith no evidence of a recurrence for six months.