[The ocular hypotensive effect of the combination of latanoprost with dorzolamide]

To analyze the hypotensive effect and ocular tolerance produced by the association of a topic carbonic anhidraze inhibitor (dorzolamide--Trusopt) and a prostaglandin derivative (latanoprost--Xalatan) in the treatment of the hypertensive glaucomas.

The study includes two steps: STEP I: A double-blind randomized prospective study which includes 32 eyes with primary open angle glaucoma, divided in two groups: group A, in which Trusopt is administrated for 7 days and then Xalatan is associated for another 7 days and group B, in which the order is reversed: for the first 7 days only Xalatan is administrated and then for another 7 days, Trusopt is associated in the treatment. The intraocular pressure and the secondary effects were assessed daily. STEP II: An open clinical trial that includes 47 eyes with different types of glaucomas in which the combination Trusopt + Xalatan was used for 90 days. The intraocular pressure and the secondary effects were assessed weekly.

In the first study (step I) the combination Trusopt + Xalatan induces an additive type of ocular hypotensive effect which is not depend by the order of the two drugs used in the beginning of the treatment (37.49% for group A and 39.16% for group B); In the clinical trial for medium term (step II), the combination Trusopt + Xalatan results in a decrease of IOP, which varies between 27.94% and 37.02% and was stable on the whole period of the study; We observed the following secondary effects: conjunctival hyperemia (6 cases), burning sensation (3 cases), foreign body sensation (1 case), itching (2 cases) and hazing (1 case).

The association Trusopt + Xalatan results in an additive ocular hypotensive effect which was stable on the whole period of the study (medium term); The ocular tolerance of this combination is good and was not followed by the interruption of the treatment.