For the prevention of postoperative
ocular infections prophylactic topical
antibiotics are routinely used. Studies evaluating comparative difference between single dose versus multiple dose administration on aqueous humour concentration of
moxifloxacin are lacking. This study compared the aqueous humour concentration of
moxifloxacin following its
topical administration in rabbit eyes with two dose regimens. Twelve albino rabbits were divided into two groups. In group-1, two drops were administered thrice (total six drops) at 2 min intervals, in both the eyes; in group-2, two drops of
moxifloxacin were administered three times a day for three days and also two h before aqueous humour collection i.e. on fourth day. Mean aqueous humour concentrations were calculated and compared using Student's 't' test and P<0.05 was considered significant.
Moxifloxacin concentration in aqueous humour in group-1 was 23.79 μg/ml and in group-2 was 42.08 μg/ml. Both dosing regimens produced substantially higher aqueous concentrations than the known minimum inhibitory concentration for most bacteria.
Moxifloxacin concentration in aqueous humour with multiple instillations is significantly higher than single instillation (P<0.05), which is adequate to cover
ciprofloxacin-resistant gram-negative bacteria. Repeated topical
moxifloxacin administration achieved significantly higher aqueous humour concentrations than single administration.