Contact lenses are thin, transparent medical devices placed directly on the cornea, the clear, dome-shaped surface at the front of the eye. They function by correcting refractive errors, such as nearsightedness or farsightedness, to improve visual acuity. Because these devices rest on a delicate biological structure, they are regulated and require a specific prescription from an eye care professional. Determining if contacts are a viable option involves a thorough medical evaluation and a commitment to proper handling and hygiene.
Basic Eligibility and Starting the Process
The first requirement for wearing contact lenses is a comprehensive eye examination to assess the overall health of the eye and determine the necessary vision correction. This initial step checks for any underlying ocular conditions that could interfere with safe contact lens wear. Contacts are only legally available with a current prescription, which mandates regular check-ups.
Following the general eye exam, a separate contact lens fitting or evaluation is required, even if you do not need vision correction. This involves specific measurements to ensure the lens rests appropriately on the eye’s surface. An eye care professional will measure the curvature of your cornea using an instrument called a keratometer or a corneal topographer.
They also measure the diameter of your iris and pupil to select the correct size and design of the lens. A poorly fitting lens can cause discomfort, blurred vision, or even damage the corneal tissue. Successful fitting leads to a trial period with sample lenses, during which you receive hands-on training for insertion, removal, and care.
Medical and Environmental Restrictions
Certain medical conditions can temporarily or permanently prevent an individual from being a suitable candidate for contact lenses. Severe dry eye syndrome is a common contraindication, as the lack of sufficient tear film volume or quality can cause chronic discomfort and increase the risk of corneal irritation. People with recurrent eye infections, such as frequent conjunctivitis, may also be advised against contact lens wear until the underlying issue is controlled.
Uncontrolled eye allergies, where the eyes frequently become red, itchy, and swollen, can also make lens wear impractical or unsafe. Furthermore, corneal conditions like advanced keratoconus, which causes an irregular cone-like bulge on the cornea, may require specialized lenses or rule out standard soft lenses entirely. In these cases, a medical professional must evaluate the risk versus the benefit.
Environmental factors also place restrictions on contact lens use. Exposure to water while wearing lenses is strongly advised against, whether swimming, showering, or using a hot tub. Water, including tap water, can harbor microorganisms like Acanthamoeba, which can adhere to the lens material and cause a rare but severe and sight-threatening eye infection.
Current safety recommendations permit contact lens use in chemical or dusty environments, provided that appropriate industrial safety eyewear, such as goggles or safety glasses, is worn over the contacts. The primary concern is that a foreign body or chemical splash could be trapped between the lens and the eye, potentially making removal difficult or delaying first aid.
Understanding Different Types of Lenses
Once eligibility is confirmed, a wide variety of lens types exist to address different vision needs and lifestyle preferences. Soft contact lenses are the most widely prescribed option, made from flexible, water-containing plastics that conform easily to the eye’s shape. These are comfortable for most wearers and come in various replacement schedules, including daily disposable, bi-weekly, or monthly.
Daily disposable lenses offer the highest level of hygiene because a fresh, sterile pair is used each day and discarded after a single wear. Alternatively, Rigid Gas Permeable (RGP) lenses are made from durable materials that do not contain water and offer exceptionally sharp vision, often recommended for individuals with specific corneal irregularities. RGP lenses require a longer initial adaptation period than soft lenses, though they are highly resistant to deposit buildup.
Specialized lenses are available for more complex prescriptions. Toric lenses are designed with a specific orientation and weighted mechanism to correct astigmatism, a condition where the cornea is irregularly curved. Multifocal or bifocal lenses are available for individuals needing correction for both distance and near vision, often due to age-related changes in focusing ability.
Essential Care and Safety Rules
Safe contact lens wear depends heavily on a strict hygiene routine to prevent eye infections, which are largely caused by improper lens care. Always wash your hands thoroughly with soap and water and dry them with a lint-free towel before touching your lenses or eyes. This simple action significantly reduces the transfer of microbes from your hands to the lens surface.
Lenses that are not daily disposables must be cleaned and disinfected after every use using only fresh, sterile contact lens solution recommended by your eye care provider. Never use tap water or saliva to rinse or store lenses, as neither is sterile, and water can introduce harmful organisms. Old solution should never be topped off; the case must be emptied, rinsed with fresh solution, and air-dried between uses.
Adhering to the prescribed replacement schedule is non-negotiable; wearing lenses past their recommended lifespan allows protein and lipid deposits to accumulate, increasing the risk of irritation and infection. Unless specifically prescribed as a continuous wear option, lenses should never be slept in, as sleeping drastically reduces the oxygen supply to the cornea. Any symptoms of severe redness, pain, persistent irritation, or sudden changes in vision necessitate immediate lens removal and consultation with a medical professional.