Causes of Sudden High Eye Pressure

Elevated eye pressure (ocular hypertension) occurs when there is a disturbance in the production and drainage of the fluid inside the eye. This fluid then accumulates, causing the pressure to rise, which can damage the optic nerve. To identify the causes of sudden high eye pressure, an ophthalmologist may examine and gently touch your eyes while observing you for any signs that your vision may be getting worse.

The biggest risk is developing glaucoma. Significantly elevated eye pressure can lead to vision loss or blindness. Prescription eye drops and a limited number of surgical options are currently the most effective ways to treat glaucoma. You don’t usually need treatment for ocular hypertension alone, but monitoring the condition before it progresses to glaucoma is crucial for long‑term eye health.

What Does Sudden High Eye Pressure Mean?

Eye pressure is defined as the pressure of the fluid within the eye. In many ways, it is similar to high blood pressure in the body. This fluid (the aqueous humor) helps maintain the shape of the eye and supplies nutrients to vital structures. However, when the fluid pressure rises, it can cause visual problems ranging from difficulty seeing in dim light to retinal detachment.

Glaucoma is always associated with elevated intraocular pressure, but ocular hypertension by itself may only require observation to make sure there is no damage, without the need for medical or surgical treatment.

Symptoms of Sudden High Eye Pressure

In most patients, an increase in eye pressure causes no noticeable symptoms (except in acute angle‑closure glaucoma, which presents suddenly with severe pain). Therefore, the only way to detect ocular hypertension is through a comprehensive eye exam in which the intraocular pressure is measured using a test called tonometry.

When high eye pressure causes glaucoma (meaning it has begun to damage the optic nerve), this also usually goes unnoticed unless an eye exam is performed. Early in the disease, vision loss tends to be subtle and is often not recognized until the disease reaches more advanced stages.

How Do You Know If You Have High Eye Pressure?

Generally, it is difficult for a person to know if they have high eye pressure, because it usually causes no obvious symptoms and the causes of sudden high eye pressure may not be clear. The condition can only be detected by an eye doctor performing a thorough eye examination, measuring the pressure inside the eye and comparing it to normal levels.

Your ophthalmologist will numb your eyes with anesthetic eye drops, then gently place an instrument on the surface of the eye to directly measure the pressure. This device provides very accurate readings. So, if you have mildly elevated pressure but no other changes, the ophthalmologist will still be able to identify this through the exam and testing.

Normal eye pressure ranges from about 12 to 22 millimeters of mercury (mmHg). If it is higher than 22 mmHg, your doctor may conduct a more extensive evaluation to look for signs of possible damage. Several factors can be considered among the causes of sudden high eye pressure, including:

If you have elevated fluid pressure, your doctor will also examine your eyes to check for:

When Is High Eye Pressure Dangerous?

High eye pressure increases your risk of glaucoma, which is why people with ocular hypertension are considered “glaucoma suspects.” Because glaucoma damages the optic nerve and can eventually lead to permanent vision loss, your ophthalmologist will likely want to monitor your eye pressure closely and advise you on steps to lower it.

Glaucoma can cause symptoms such as severe eye pain and throbbing, headache, blurred vision, nausea and vomiting, eye redness, or seeing halos around lights. If you experience any of these symptoms, seek immediate care with your eye doctor at Al Batal Specialized Center.

List of Causes of Sudden High Eye Pressure

All cases of elevated intraocular pressure (high eye pressure) result from an imbalance between the production and drainage of the aqueous humor. There are several reasons this can occur.

Primary glaucoma refers to cases in which no clear cause is identified. Secondary glaucoma can be caused by trauma or injury, medications, or other underlying eye conditions. Factors that cause or are associated with high eye pressure include:

Excess Aqueous Humor Production

Aqueous humor is a clear fluid produced in the eye by the ciliary body, a structure located behind the iris. The fluid flows through the pupil into the anterior chamber, the space between the iris and the cornea. If aqueous humor is produced more quickly than it can drain out, pressure inside the eye increases, leading to ocular hypertension.

Insufficient Aqueous Humor Drainage

High eye pressure can also occur if aqueous humor is produced at a normal rate but drains too slowly from the eye. Some medications can have side effects that increase intraocular pressure. Steroid medications used to treat asthma and other conditions, including steroid eye drops, have been shown to increase the risk of ocular hypertension. Be sure to tell your eye doctor if you use steroid eye drops for any reason.

Eye Trauma

Eye injuries are another factor that can disrupt the balance between aqueous humor production and drainage, potentially leading to high eye pressure. Sometimes this may occur months or even years after the initial injury. During routine eye exams, make sure to inform your doctor about any recent or past eye injuries.

Glaucoma: A Direct Pathway to Sudden High Eye Pressure

Developing glaucoma itself can be one of the causes of sudden high eye pressure. Some forms of glaucoma involve damage to the retina and optic nerve without a marked rise in intraocular pressure as an early warning sign (normal‑tension glaucoma). However, other types of glaucoma cause progressive vision loss, especially if left untreated.

Some common types of glaucoma include:

Glaucoma often runs in families. Discuss your family history of glaucoma with your ophthalmologist during your routine eye exams so your doctor can detect any signs of the disease as early as possible.

Treatment of Glaucoma

Your doctor will design an individualized treatment plan for glaucoma, which may include medications or surgery. New treatments for glaucoma are continuously being developed. The most common treatment options include:

Prescription Eye Drops

There are several classes of prescription eye drops used to treat glaucoma. Your ophthalmologist may start you on one type of drop to see how well it works, or prescribe a combination of medications to better control your eye pressure.

Laser Surgery

Laser procedures are performed on an outpatient basis to treat certain types of glaucoma and improve fluid drainage. There are two main types of laser surgery commonly used to manage glaucoma.

Operating‑Room Surgery

Because they require general or regional anesthesia and have longer recovery times, operating‑room surgeries are usually reserved as a last resort. However, your ophthalmologist may recommend incisional glaucoma surgery if the disease does not respond adequately to other treatments such as laser procedures. There are two main categories of these surgeries.

Glaucoma Drainage Devices

In some cases, your doctor may need to implant a drainage tube in the eye. This tube diverts fluid to a small reservoir (bleb) placed under the conjunctiva. From there, the fluid is gradually absorbed into nearby blood vessels.

Monitoring High Eye Pressure Before It Turns Into Glaucoma

Regular eye exams are essential for maintaining long‑term eye health. Without these check‑ups, conditions like ocular hypertension or glaucoma can progress silently, and you may not realize you are slowly losing vision.

By measuring intraocular pressure, your eye doctor can detect elevated pressure and then check for any early vision loss. If there are signs that you’re starting to lose vision, as in early glaucoma, your doctor can create a treatment plan to slow the progression of the disease. Ongoing monitoring helps ensure that your eyes remain as healthy as possible.

Treatment of Sudden High Eye Pressure

The goal of medical treatment is to lower eye pressure before it causes glaucoma‑related vision loss. Medical therapy is typically initiated in people who are considered at higher risk for glaucoma or who already show signs of optic nerve damage.

How your ophthalmologist chooses to treat you is highly individualized and depends on your specific situation. You may be managed with medications, and your doctor will discuss with you the pros and cons of starting treatment versus careful observation.

Some ophthalmologists treat all consistently elevated eye pressures above 21 mmHg with topical medications. Others do not start medical treatment unless there is evidence of early optic nerve damage, as shown by changes in the appearance of the optic nerve, visual field defects, or abnormalities on OCT (optical coherence tomography). Many eye doctors will treat if pressures are persistently above about 28–30 mmHg (approaching 40 mmHg), because the risk of optic nerve damage is high at those levels.

If you have symptoms such as halos around lights, blurred vision, eye pain, or if your eye pressure has recently risen and continues to increase at follow‑up visits, your ophthalmologist is more likely to start medical treatment. If your pressure is 28 mmHg or higher, you will usually be started on medication. After one week to one month on the medication, you’ll have a follow‑up visit so your doctor can see whether the drops are effectively lowering the pressure and whether there are any side effects. If the medication works well, follow‑up appointments are typically scheduled every three to four months.

In a large study of nearly 3,300 people between the ages of 40 and 80, researchers looked at treating high eye pressure before glaucoma develops. Over many years of follow‑up, they found that there was no major difference in outcomes between patients who received immediate treatment and those who were only observed. Overall, regular eye exams remain the best way to protect your vision. Early diagnosis and timely intervention make it possible to slow disease progression and preserve your sight.