For anyone who relies on contact lenses, the occasional irritation, dryness, or itchiness is a common experience. The immediate instinct is to reach for eye drops, but whether they can be used while wearing lenses is conditional. It depends completely on the specific formulation of the drop and the chemical compatibility with the lens material. Using the wrong product can lead to discomfort, blurred vision, or even damage to the lenses and the ocular surface.
Drops Designed for Direct Contact Use
When seeking relief while your lenses are still in place, you must choose products specifically formulated for this purpose, often labeled as “re-wetting drops” or “contact lens drops.” These specialized solutions are designed to safely lubricate the lens and the eye surface, restoring lost moisture and enhancing comfort. Many of these drops contain ingredients like sodium hyaluronate or gentle polymers that help to rehydrate the lens material itself. This is especially beneficial for soft lenses that can dry out over time and cause discomfort.
These drops work by supplementing the natural tear film that can be disrupted by lens wear, allowing the lens to move more smoothly across the cornea. To ensure a product is safe for direct use, always check the packaging for explicit labeling that confirms compatibility with your lens type, such as “safe for use with soft and RGP lenses.” Some formulations may also contain mild, non-depositing preservatives that are safe for the lens material, or they may be entirely preservative-free, which reduces the risk of buildup.
Categories of Drops That Require Lens Removal
Most standard over-the-counter eye drops are not safe for use with contacts and require lens removal due to the risk of chemical binding and material damage. One major category to avoid is redness relief drops, which contain vasoconstrictors like Tetrahydrozoline or Naphazoline. These chemicals shrink the tiny blood vessels to reduce redness. If applied while wearing lenses, the lens material can absorb and concentrate the vasoconstrictor, leading to a prolonged exposure that can irritate the eye and potentially worsen redness over time.
Other formulations like thick gels or ointments intended for severe dry eye must also be avoided while wearing contacts. The high viscosity and oily nature of these products will immediately coat and cloud the lens surface, creating a sticky film that attracts debris. Similarly, medicated or prescription drops, such as those containing antibiotics or steroids, are generally incompatible with contact lenses. The active pharmaceutical ingredients in these drops can be absorbed and held by the lens, leading to a higher-than-intended concentration on the eye’s surface and potentially compromising the drug’s effectiveness or causing ocular surface damage.
Ingredient Interactions and Lens Safety
Incompatibility often lies in the chemical interaction between certain ingredients and the porous nature of contact lens materials, especially soft hydrogel lenses. A primary concern is the presence of Benzalkonium Chloride (BAK), which is one of the most common preservatives used in ophthalmic solutions. BAK is a cationic surfactant that, while effective at preventing microbial contamination, is highly damaging to contact lenses.
Soft lenses, particularly those with a higher water content, readily absorb and concentrate BAK within their polymer matrix. This absorption leads to a slow, continuous release of the preservative onto the eye’s surface, which can cause toxic keratitis, chronic irritation, and discoloration of the lens itself. Therefore, unless a drop is explicitly labeled as contact lens-safe, the presence of any preservative, especially BAK, means the lenses must be removed prior to application.
If you must use a drop that is incompatible with your lenses, the proper procedure is to remove the contacts first, apply the drops as directed, and then wait a period of 10 to 15 minutes before reinserting your lenses. This wait time allows the eye to absorb the medication or solution and flush the potentially harmful ingredients from the ocular surface. Following this rule significantly reduces the risk of lens contamination and eye irritation.