Moon Blindness

By: Dr. Lydia Gray

What is it?

Moon Blindness, technically known as Equine Recurrent Uveitis or ERU, is one of the most common eye diseases of horses and the leading cause of equine blindness. It gets its name from the waxing and waning course of the disease, where active bouts of inflammation are followed by weeks, months or even years of apparent inactivity. However, ERU is an immune-mediated disease where the body's own immune cells may continue to attack eye tissue in between obvious episodes. These attacks produce signs such as squinting, tearing, "red eye," a cloudy eye, swelling and sensitivity to the sun.

What can be done about it?

If an underlying cause for the condition can be found during the physical or ophthalmolgical examinations, this should be specifically treated. Aggressive anti-inflammatory medications - steroid and non-steroidal--are generally prescribed both topically (in the eye) and systemically (injected or fed) to limit eye tissue damage. Dilating agents may also be used to relieve pain and prevent complications. Naturally occurring compounds such as MSM that help fight inflammation may be helpful as well. Consistent treatment and follow-up are important because each attack causes more permanent damage, which can eventually lead to blindness. Some horses remain on anti-inflammatories for life, in an attempt to prevent flare-ups of the disease. Fly masks can be a helpful management tool during and between attacks to protect the eyes

What else do I need to know?

There is a genetic component to this disease, as appaloosas are more likely than other breeds to develop ERU and more likely to become blind as a result. While there is a surgical procedure to save severely affected eyes, an eye that is blind and painful should probably be removed (enucleated).

About Dr. Lydia Gray

Have questions? Contact us »
Connect with us:

Brittany and Nate
Ever since I was the girl with 1,000 breyer horses and the raggity braid in her hair, I was always obsessed. In second grade I moved into a town with a barn right down the street, which is when I started taking lessons...

Learn more »

Recipe: Homemade Carrot and Oat Treats
It has been such a cold and snowy winter here in Massachusetts for the past few months. I look for any excuse to fire up my oven. Prior to visiting my horse Bug last weekend I decided to make her

Read More »

Download our mobile apps

Put SmartPak in your pocket with these awesome apps!

Check It Out »

Healthy horses, happy riders.
SmartPak is committed to a greener planet.
Sign Out
Sign Up Now!
Free Catalog Get Yours Now!

SmartPak Equine™ is the premier online provider of horse supplies and equine supplements.
Questions? Call us Toll-Free at 1-888-339-9695. © Copyright 2014 by SmartPak Equine LLC. All Rights reserved.