Although it is well known that intraocular pressure (IOP) in humans va
ries throughout day and night, no consistent circadian pattern has bee
n established. In laboratory rabbits, however, a consistent circadian
rhythm of IOP has been confirmed and further characterized in recent y
ears. The current knowledge about the nocturnal IOP elevation in rabbi
ts is reviewed and the implications for the study of human circadian I
OP pattern is discussed.