Eye drops can silently harm your vision? Doctors warn how simple eyecare habit can seriously damage eyes

You rub your tired eyes at the end of a long day, notice redness or dryness and instinctively reach for that old bottle of eye drops tucked away in your medicine cabinet. It seems like a no-brainer, a quick fix for irritation but according to leading eye care specialists, the convenience of over-the-counter (OTC) or leftover prescription drops can come at a hidden cost.

In an interview with the Times of India, Dr Rajul Agarwal, Consultant Ophthalmologist at Ujala Cygnus Group of Hospitals, shared, “While eye drops may seem harmless, using them without a prescription or guidance can silently cause more harm than good. Eyes are very sensitive organs, and great care should be taken in managing any condition that might surface in our day-to-day life. Reaching out for over the counter drops out of convenience is ill-advised and it might worsen the infections or cause long-term damage.”




Bringing her expertise to the same, Dr Jyotsna Soni, Associate Consultant Ophthalmology at Regency Health in Kanpur, echoed, “Many‍‌‍‍‌‍‌‍‍‌ people intuitively reach for eye drops when their eyes are red, dry, or irritated. It generally looks like a fast and harmless remedy, especially when the drops are bought over the counter or are left over from a previous prescription. However, dropping them without proper guidance can result in more damage to your eyes rather than healing them.”

Redness relief can backfire: Rebound redness and irritation

One of the most significant issues is the use of medicated drops, such as steroids or antibiotics, without a doctor’s advice. Dr Soni explained, “For a while, steroid drops may relieve redness or irritation and make you feel better, but if you use them for too long or in the wrong way, they can increase the pressure in your eye and cause glaucoma. Besides, they can suppress the symptoms of infection, thus making it more severe without you knowing it. Antibiotic drops should be administered only to bacterial infections. Therefore, using them in other cases will not be beneficial and may make bacteria more resistant to treatments.”

Using over-the-counter eye drops may seem straightforward but it can actually be complicated if not done correctly. Dr Soni revealed, “Many redness relief drops contain ingredients that constrict blood vessels, making your eyes appear whiter. However, frequent use of these products can lead to increased redness once their effects wear off. Additionally, some drops contain preservatives, which can cause discomfort if used regularly, especially for those with sensitive eyes.”

Dr Agarwal said, “A common issue arises with redness-relieving drops, which often contain vasoconstrictor ingredients that shrink blood vessels to reduce redness temporarily. While they provide quick relief, repeated use can create a “rebound effect,” where redness worsens once the drops wear off. Over time, this can lead to chronic irritation and dependence, which might have a damaging effect.”

Many redness-relieving OTC drops contain vasoconstrictors, which shrink blood vessels to “whiten” the eye temporarily but this relief can be a trap. A 2019 review in Clinical Ophthalmology found that frequent use of vasoconstrictive eye drops can lead to rebound redness and chronic irritation, as the blood vessels dilate more aggressively once the drop’s effect wears off. The researchers noted, “Frequent use of vasoconstrictor-containing ocular decongestants may lead to a cycle of worsening redness and discomfort.”

Steroid and antibiotic drops: Not always innocent

Another growing concern is the leftover prescription eye drops that are just as risky. Dr Agarwal explained, “Drops prescribed for infections, allergies, or inflammation are formulated for specific conditions and for a set duration. Using them later, for unrelated symptoms, may mask the real problem and delay proper diagnosis. Steroid-based drops, in particular, when used without supervision, may worsen undiagnosed infections, increase eye pressure, and eventually lead to glaucoma or cataracts when used inappropriately.”

Not known to many, once opened, eye drops have a limited shelf life. Dr Agarwal elaborated, “Bottles stored for months, kept in warm places, or handled incorrectly can accumulate bacteria and contaminate the eyes, increasing the risk of serious infections like keratitis or conjunctivitis. In severe cases, such infections can cause scarring and even vision loss if not treated promptly.”

Prescription eye drops serve specific conditions like infections, severe allergies or inflammation. Using them outside of their intended context can be dangerous. An influential 2018 study in Ophthalmology showed that unsupervised use of steroid eye drops significantly increases intraocular pressure, a key risk factor for glaucoma and may accelerate cataract development when used long-term. The authors found, “Topical corticosteroids elevate intraocular pressure in susceptible individuals and can contribute to glaucoma risk.”

Antibiotic drops, meanwhile, should only be used for bacterial infections. Misusing them can contribute to antibiotic resistance and fail to address viral or allergic causes.

Contamination and expiry: A hidden infection risk

Reusing expired eye drops is a great mistake that commonly arises in eye care practices. Frequently, people keep bottles of eye drops long after they have been opened and use them again when they experience symptoms again. Dr Soni cautioned, “Eye droppers can expire once they are opened, or they can be contaminated. Using improperly stored drops or unsanitary drops can cause significant eye infections that may require immediate intervention.”

According to her, this risk can be especially problematic, since eye problems typically develop over time (often undetected) or appear minimally at first, only showing evidence of a problem after the injury or dysfunction has already begun to affect your eye and vision. Dr Soni pointed, “In many cases, you may experience short-term relief from drops; however, the actual pathology beneath that temporary relief may continue to worsen, undetected. By the time you experience symptoms, including pain or the error, you may be in a medically emergent situation.”

Eye drop bottles are not immortal. Once opened, they offer a route for microbes to enter, especially if stored improperly or re-used long after expiry. A 2023 study in Journal of Ophthalmic Inflammation and Infection found that contaminated eye drops can harbour bacteria and fungi, significantly increasing the risk of keratitis, conjunctivitis and other sight-threatening infections. The study highlighted, “Contaminated ophthalmic solutions pose a serious risk of infectious keratitis, particularly in eyes with pre-existing surface compromise.”

More than lubrication: When even ‘safe’ drops hurt

Many people also assume that OTC lubricating drops are universally safe but even these can contain preservatives that irritate sensitive eyes when used too frequently. Dr Agarwal advised, “For individuals with chronic dry eye, preservative-free formulations or targeted treatment plans are often more suitable than self-medicating with random OTC options.”

When to see a doctor

Avoiding self-treatment of eye pathology is likely the best way to proceed further. Dr Soni recommended, “If your eyes are red, dry, or irritated for more than a very brief period of time, or if you notice a change in vision, consider visiting your ophthalmologist to get your eyes evaluated. Putting the right treatment in your eyes may provide immediate benefit to you, and it may help to prevent long-term issues from developing.”

Prevention being better than cure, one should avoid using leftover drops and resist the urge to self-diagnose with OTC products, especially for persistent or unexplained symptoms. Dr Agarwal suggested, “If you experience redness, pain, blurred vision, or discharge, consult an eye care professional instead of taking matters into your own hands. Keep in mind that temporary comfort might have long-term consequences that can be far more serious. Protecting your eyes starts with informed choices and timely professional guidance.”

Takeaway: In eye care, informed choices protect vision

It may seem convenient to grab the nearest bottle of drops but the impulse to self-treat can cost you dearly. From rebound redness and steroid risks to contaminated bottles and preservative irritation, the science and specialists agree that eyes deserve careful, informed care. If your symptoms persist, change in nature, or are accompanied by pain or vision changes, consult your ophthalmologist. Protecting your eyes starts with informed choices and timely professional care.

Note: The information provided in this article is for educational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any new medication or treatment and before changing your diet or supplement regimen.