Sildenafil citrate, sold under the brand name Viagra for erectile dysfunction, has been found effective at treating ocular hypotension or shallow anterior chamber after surgery, according to a virtual presentation at the Association for Research in Vision and Ophthalmology conference.

Researcher Dr. Maria Gomez Chapo said, “In previous studies, sildenafil 50 mg and 100 mg was shown to produce a substantial increase of intraocular pressure in an animal model.”

“The purpose of the current study was to test the same drug in human volunteers with normal IOP [intraocular pressure] in the city of Corrientes, Argentina.”

The study included 15 healthy participants, aged between 19 and 55, who were divided into two groups. One group received a dose of sildenafil citrate 100 mg, while the other a placebo.

The researchers then measured IOP using Goldmann applanation tonometry at baseline, after 1.5 hours, and then after 4 hours of the dosage.

Dr. Gomez Chaop said, “Mean IOP at baseline was 16.2 mm Hg. Following administration of sildenafil, it increased 90 minutes later to 17.7 mm Hg and remained higher after 4 hours, with a little reduction of 0.3 mm Hg as compared with the previous measure.”

The findings suggest that sildenafil, which was initially approved for the treatment of pulmonary arterial hypertension, has IOP-elevating effects, prompting the researchers to conclude that the drug could be used to treat ocular hypotension – a lack of production or a loss of intraocular fluid.

Dr. Gomez Chapo said no significant changes in IOP were reported in participants who received a placebo.

She said, “An increase of IOP was observed in all the cases studied, even 4 hours after the intake of the drug.” “Though high, the IOP did not exceed the normal IOP values, and no difference was observed in the elevation of IOP according to age,” Dr. Gomez Chapo added.