The effect of isosorbide dinitrate (ISORDIL ) on intraocular pressure (IOP)was studied using rabbits as experimental animals. There was a net decrease in IOP following administration of the drug. The study rabbits were divided into 2 groups (the 10mg per day group and the 20mg per day group) of 4 rabbits each. The initial IOP was taken before administration of the drug. The first group was given lml of 10mg/ml solution of the drug orally, once daily for five days and the second group received same regimen orally, but was given 2ml of the 10mg/ml solution. The IOP was monitored for seven days using Schiotz indentation tonometer. Statistical analysis using ANOVA showed significant difference (P>0.05) between the means of various days in the second group. There was no significant difference (P<0.05) between the means of various days in the first group. It can be inferred from the study that ISORIDIL has no threatening effect on the ocular integrity if taken at normal does but one should guide against overdose as it might significantly raise the IOP.