A common class of antibiotics was linked to a higher risk of so-called retinal detachment - when the light-sensitive tissue in the eye separates from gel that fills the eyeball, in a new Canadian study.
People treated by ophthalmologists for the emergency condition were five times more likely to be taking drugs known as fluoroquinolones, which include ciprofloxacin (marketed under names including Zoxan, Proquin and Cipro) and levofloxacin (Levaquin, Cravit), than those who didn't have retinal detachment.
"We know that these drugs are toxic to connective tissue and cartilage," said Mahyar Etminan, the study's lead author, noting past studies linking fluoroquinolones with damage to Achilles and shoulder tendons.
"We wanted to see whether this damage also may translate in the eye, because there's lots of connective tissue in the eye," Etminan, from the Child and Family Research Institute of British Columbia in Vancouver, told Reuters Health.
Retinal detachment, which starts as the appearance of lines, dots or "floaters" across the eye, can cause permanent blindness in some cases if it's not surgically treated within a few days.
Etminan and his colleagues used data from doctors' treatment records for everyone in British Columbia who saw an ophthalmologist between 2000 and 2007 - almost one million patients. That included about 4,400 people diagnosed with retinal detachment when they were an average of 61 years old.
Prescription records showed that one out of every 30 patients with retinal detachment was taking a fluoroquinolone at the time, most commonly ciprofloxacin. Most antibiotic users were taking the drugs for respiratory or urinary tract infections.
Among a similar group of patients who visited an ophthalmologist but didn't have retinal detachment, just one in 167 had been recently prescribed the antibiotics.