Whether over-the-counter eye drops can be used while wearing contact lenses is a common question. Certain types of eye drops are safe for use with contacts, while many others are not. This distinction is based on the chemical composition of the drops and how their ingredients interact with the lens material. Understanding the difference between compatible and incompatible solutions is necessary for maintaining eye comfort and lens integrity.
Understanding Contact Lens Compatibility
The primary reason to differentiate eye drop types is the physical composition of the contact lens itself. Modern soft contact lenses are made from hydrogel or silicone hydrogel materials designed to absorb and hold water, keeping them soft and pliable. This absorbent nature means the lens can soak up ingredients from non-compatible eye drops, concentrating them against the eye’s surface.
A major concern is the presence of preservatives, such as benzalkonium chloride (BAK), frequently found in multi-dose eye drop bottles to prevent microbial growth. When BAK is absorbed by the lens material, it can be slowly released onto the ocular surface, potentially causing irritation, redness, or toxicity to corneal cells with repeated use. The absorbed chemicals can also lead to the clouding or discoloration of the lens, reducing its clarity and lifespan.
Safe Drops: Rewetting and Lubricating Solutions
The safest products for use while wearing contacts are those explicitly labeled as rewetting or lubricating drops for contact lens wearers. These solutions are formulated to be pH-balanced and isotonic, meaning they closely match the natural chemistry of the tear film. They restore moisture to the lens surface and the eye, helping to relieve dryness and minor irritation without altering the lens shape or comfort.
Rewetting drops are designed to be applied directly over the lens to rehydrate it and improve comfort. They are often thinner in viscosity and help flush away small debris trapped beneath the lens without causing clouding. Lubricating solutions, sometimes called artificial tears, supplement the eye’s natural tear film, but only specific formulations are safe for contacts. Many approved contact lens drops are preservative-free, often coming in single-use vials, which eliminates the risk of preservative buildup.
Drops to Avoid While Wearing Contacts
A major category of drops to avoid while wearing lenses is redness-relieving drops. These typically contain vasoconstrictors, such as tetrahydrozoline or naphazoline, which temporarily shrink the tiny blood vessels to reduce redness. The contact lens can absorb these active ingredients and hold them against the eye for an extended time, significantly prolonging the drug’s effect.
This concentration can lead to “rebound redness,” where blood vessels dilate excessively once the drug wears off, causing the eyes to become redder. Furthermore, vasoconstrictors can reduce the flow of oxygen and nutrients to the cornea, a problem compounded by the contact lens. Other drops to avoid include thick gel-based artificial tears, which can permanently coat and cloud the lens, and most prescription medicated drops, unless specifically approved by an eye care professional.
Application Techniques for Optimal Comfort
For drops explicitly labeled for use with contacts, the application technique is straightforward and can be done while the lenses are in place. Always wash hands thoroughly to prevent transferring debris or microbes to the eye or the dropper tip. Tilt your head back, look up, and gently pull down the lower lid to create a small pocket for the drop.
If you are using a drop not approved for contact lens wear, such as a general artificial tear or a medicated solution, you must remove your lenses first. After instilling the drops, wait a minimum of 10 to 15 minutes before reinserting your contacts. This waiting period allows the eye to absorb the solution and flush away incompatible ingredients. If dryness persists, consult an eye doctor for evaluation, as frequent rewetting drops may mask an underlying problem.