Uveitis: Eye Inflammation, Causes, and Steroid Therapy

Uveitis is not just a red eye. It’s a serious inflammation deep inside the eye that can steal your vision if ignored. Unlike a simple irritation from dust or tiredness, uveitis attacks the uvea - the middle layer of your eye that feeds the retina, controls the pupil, and helps maintain eye pressure. When this layer swells, it doesn’t just hurt. It can scar tissue, block fluid flow, and permanently damage the retina or optic nerve. The good news? If caught early, it’s often treatable. The catch? Most people don’t recognize the signs until it’s too late.

What Exactly Is the Uvea?

The uvea isn’t one thing - it’s three parts working together. First, the iris, the colored part of your eye, controls how much light enters. Then comes the ciliary body, which makes the fluid inside your eye and helps you focus. Finally, the choroid is a rich network of blood vessels behind the retina that delivers oxygen and nutrients. When inflammation hits any of these layers, your eye’s entire system goes off balance. Fluid builds up. Pressure changes. Cells start to die. And vision? It gets blurry, distorted, or worse.

The Four Types of Uveitis - And Why It Matters

Not all uveitis is the same. Where the inflammation happens changes everything - from symptoms to treatment. There are four main types:

• Anterior uveitis - This is the most common, making up 75-90% of cases. It affects the front of the eye - the iris and ciliary body. Symptoms hit fast: sharp pain, redness, light sensitivity, and blurred vision. You might notice it when reading, because focusing makes the pain worse. It’s often isolated to one eye and responds well to eye drops.
• Intermediate uveitis - Also called pars planitis, this targets the vitreous, the jelly-like fluid in the center of the eye. It doesn’t always hurt. Instead, you’ll see floaters - dark spots or squiggly lines - and your vision gets foggy. It’s sneaky. Often, it lasts for months or years, coming and going. It’s the most likely to cause macular edema - swelling in the part of the retina that gives you sharp central vision.
• Posterior uveitis - This affects the back of the eye: the retina and choroid. It’s rare but dangerous. Symptoms creep in slowly. You might not notice anything until vision drops. It often hits both eyes. This is where permanent damage happens - retinal scarring, optic nerve injury, and even blindness. Many cases are only caught during routine eye exams.
• Panuveitis - This is the worst-case scenario. Inflammation spreads through all three layers at once. You get the pain of anterior uveitis, the floaters of intermediate, and the vision loss of posterior. It’s aggressive, hard to treat, and linked to serious autoimmune or infectious diseases.

Knowing which type you have isn’t just academic. It determines how you’re treated - and how urgently.

What Causes Uveitis? The Real Culprits

You’d think it’s just an infection or injury. But in nearly half of all cases, doctors can’t find a clear cause. That’s called idiopathic uveitis. The rest? They’re tied to bigger problems in your body.

• Autoimmune diseases - Your immune system turns on your own eye tissue. Conditions like ankylosing spondylitis (a spine disorder), multiple sclerosis, sarcoidosis, and rheumatoid arthritis are common triggers. If you have one of these, your eye inflammation might be the first sign.
• Infections - Viruses like herpes simplex (cold sores) or herpes zoster (shingles) can creep into the eye. Fungal infections like histoplasmosis, bacterial ones like syphilis, or parasites like toxoplasmosis (from undercooked meat or cat litter) can also cause uveitis. These often show up in people with weakened immune systems.
• Trauma or surgery - A blow to the eye, a scratch, or even eye surgery can trigger inflammation. Sometimes, it happens weeks after the event.
• Unknown causes - About 30-40% of cases have no identifiable trigger. That doesn’t mean it’s harmless. It just means treatment has to be more aggressive.

Doctors don’t just look at your eye. They ask about back pain, joint swelling, skin rashes, or recent infections. Uveitis is often a red flag for something deeper.

Steroid Therapy: The First Line of Defense

When inflammation is the enemy, steroids are the most powerful weapon. They don’t cure the root cause - but they stop the damage while doctors figure out what’s behind it.

Anterior uveitis - Treatment starts with steroid eye drops. Prednisolone acetate 1% is the go-to. You’ll use it every hour at first, then slowly reduce over weeks. Pupil-dilating drops are added to stop the iris from sticking to the lens - a complication called synechiae that can raise eye pressure and cause glaucoma.

Intermediate uveitis - Eye drops don’t reach far enough. Doctors turn to injections around the eye (periocular) or oral steroids like prednisone. In stubborn cases, an implant that slowly releases steroids inside the eye (like Ozurdex) is used. It lasts months, reducing the need for daily pills.

Posterior uveitis - This is serious. Oral steroids are standard. Sometimes, high-dose IV steroids are given in the hospital. If the inflammation is tied to an infection like CMV, antiviral drugs are added. Steroid implants here are common because they deliver high doses directly to the retina without flooding the whole body.

Panuveitis - Requires a full attack: oral steroids, sometimes IV, and often long-term immune-suppressing drugs. The goal isn’t just to calm the eye - it’s to stop the body from attacking itself.

But steroids come with risks. Long-term use can cause cataracts (clouding of the lens) in up to 40% of patients. It can also spike eye pressure, leading to glaucoma. That’s why treatment isn’t about taking steroids forever - it’s about using them just long enough to save your vision, then switching to safer, long-term options.

What Happens After Steroids?

If uveitis keeps coming back, or if you need steroids for more than a few months, your doctor will likely switch to steroid-sparing therapies. These are drugs that calm the immune system without the side effects of steroids. Examples include methotrexate, mycophenolate, azathioprine, or biologics like adalimumab. These take weeks to work, but they let you stop or lower steroid doses. For some, this is a lifelong plan.

It’s not about being “cured.” It’s about control. Uveitis can go quiet for years - then flare again. That’s why regular eye exams, even when you feel fine, are non-negotiable.

When to Act - And How Fast

Uveitis doesn’t wait. Symptoms can appear in hours. If you notice:

• Redness that doesn’t go away
• Pain that worsens when reading
• Blurred vision that comes out of nowhere
• Floaters that suddenly multiply
• Sensitivity to light - even indoors

- you need an eye doctor today. Not tomorrow. Not next week. Delaying treatment by even a few days can mean the difference between full recovery and permanent vision loss. This isn’t an emergency room situation - it’s an eye specialist emergency. A retina specialist or uveitis expert is what you need.

And don’t assume it’s just “pink eye.” Red eyes from uveitis aren’t itchy. They’re deep, aching, and light-sensitive. You won’t find this on a drugstore shelf.

Can Vision Come Back?

Yes - if caught early. Anterior uveitis, treated fast, often leaves no lasting damage. But intermediate, posterior, and panuveitis? They’re trickier. Macular edema, retinal scarring, optic nerve damage - these can be irreversible. That’s why uveitis is the third leading cause of blindness worldwide. It’s not the inflammation itself that’s deadly. It’s the delay in recognizing it.

Recovery isn’t just about clearing symptoms. It’s about preventing complications. That means ongoing monitoring. Even if your vision feels normal, your doctor will check for subtle signs of swelling, pressure changes, or early scarring.

What You Can Do - Right Now

• If you have an autoimmune disease - get yearly eye exams. Uveitis might be your first symptom.
• If you’ve had eye surgery or trauma - watch for symptoms for at least 6 weeks.
• If you’re on long-term steroids - get your eye pressure checked every 3-6 months.
• Don’t self-treat with over-the-counter drops. They won’t help - and they might hide the real problem.
• Know your family history. Some forms of uveitis run in families.

Uveitis doesn’t announce itself with a siren. It whispers. And if you ignore the whisper, it screams.

Uveitis doesn’t care how young or healthy you are. It doesn’t wait for a perfect time. It strikes silently - and steals vision quietly. If your eye feels off, don’t wait. Don’t guess. See an eye specialist. Your sight is worth the visit.