Intraocular Pressure (IOP) is the fluid pressure inside the eye, maintained by a balance between the production and drainage of aqueous humor. Stable IOP preserves the eyeball’s shape and protects the optic nerve. Elevated pressure, known as ocular hypertension, is the primary risk factor for developing glaucoma, which can lead to irreversible vision loss. While nasal sprays are common over-the-counter remedies, their active ingredients can disrupt this fluid balance in specific individuals, causing a sudden or gradual increase in eye pressure. This connection between nasal spray use and elevated IOP is a valid concern, particularly for people with pre-existing eye conditions.
Which Nasal Sprays Can Increase Eye Pressure
The potential for a nasal spray to increase eye pressure depends on its active ingredient. Nasal decongestants, which contain sympathomimetic agents like phenylephrine or oxymetazoline, represent the highest risk category. These ingredients constrict blood vessels in the nasal lining, reducing swelling and congestion, but they can also be absorbed systemically, affecting the eyes.
Nasal corticosteroids, such as fluticasone or mometasone, pose a generally lower risk. These sprays manage allergies by reducing inflammation. While steroids applied directly to the eye are known to elevate IOP, systemic absorption from nasal application is typically low. Studies indicate that for the average person, newer generation nasal steroids do not cause a significant increase in eye pressure, even with prolonged use.
However, discontinuing a nasal steroid has resulted in a measurable reduction in IOP in individuals already diagnosed with glaucoma or ocular hypertension. Saline sprays, which contain only salt water, have no pharmacological effect on the eyes and carry no risk for IOP elevation.
The Physiological Mechanism of Intraocular Pressure Increase
The way a nasal spray influences eye pressure depends on its chemical composition and route of action. For decongestants, the primary concern is systemic absorption into the bloodstream. These compounds act as adrenergic agonists, stimulating the nervous system that controls the iris muscles.
Once absorbed, the medication travels to the eye and causes the pupil to dilate (mydriasis). This dilation is problematic for people with an anatomically narrow drainage angle, the junction where the iris meets the cornea. When the pupil dilates, the peripheral iris bunches up and can physically block the trabecular meshwork, which drains the aqueous humor. This blockage prevents fluid from escaping, leading to a rapid spike in IOP known as acute angle-closure glaucoma.
Corticosteroids raise IOP through a slower, distinct mechanism unrelated to pupillary blockage. Steroid molecules accumulate in the trabecular meshwork, the spongy tissue that filters the aqueous humor. This accumulation increases resistance to fluid outflow, leading to a gradual buildup of pressure inside the eye. This effect is associated with open-angle glaucoma and is more likely to occur with long-term use in individuals genetically predisposed to be “steroid responders.”
Identifying Individuals at Elevated Risk
The highest risk for complications from nasal spray use is concentrated in individuals with specific anatomical features. People diagnosed with narrow-angle glaucoma or who are anatomically predisposed to narrow angles are highly susceptible. For these individuals, a single dose of a decongestant spray can trigger a sudden pressure spike. The risk exists even if the individual has not previously experienced eye symptoms.
Individuals with primary open-angle glaucoma or ocular hypertension face an elevated, though less acute, risk, primarily from nasal corticosteroids. These patients have compromised drainage systems, and long-term steroid use can further impede outflow, leading to a progressive rise in IOP. Other factors that increase susceptibility to steroid-induced pressure elevation include a family history of glaucoma, being over the age of 40, or having conditions like diabetes.
Before using any decongestant spray, it is advisable to consult an eye care professional, especially if a comprehensive eye examination has not been performed. This consultation can determine the configuration of the eye’s drainage angle. Understanding one’s eye health status is the most effective preventative measure.
Recognizing Acute Symptoms and Next Steps
A sudden rise in intraocular pressure is an ocular emergency requiring immediate medical attention. The symptoms of this condition, known as acute angle-closure crisis, include the sudden onset of intense eye pain, a throbbing headache, and noticeable eye redness.
Vision changes are a major indicator, often presenting as seeing rainbow-colored halos around lights or experiencing sudden blurred vision. Nausea and vomiting may also accompany the ocular symptoms due to the severe pressure spike. If any of these symptoms appear after using a decongestant nasal spray, the medication must be stopped immediately.
Seek emergency medical care at an eye doctor’s office or an emergency room without delay. Prolonged, severely elevated eye pressure can cause irreversible damage to the optic nerve in a matter of hours. Quick treatment is necessary to reduce the pressure and preserve vision.