Identifying Unsuitable Candidates
Not every patient who wants contact lenses should wear them. Part of being a responsible contact lens practitioner is recognizing contraindications: conditions, behaviors, or circumstances that make contact lens wear unsafe, unlikely to succeed, or potentially harmful. Contraindications range from absolute (never fit) to relative (fit with caution and monitoring).
Absolute Contraindications
These conditions make contact lens wear unsafe and should be resolved before fitting:
Active Eye Infection
An active bacterial, viral, or fungal keratitis is an absolute contraindication. Contact lenses can trap infectious organisms against the cornea, worsen the infection, and delay healing. The infection must be fully resolved and the cornea healed before lens wear can be considered.
Severe, Uncontrolled Dry Eye
Patients with severe dry eye that does not respond to treatment cannot maintain the tear film needed for comfortable, safe contact lens wear. The lens will dehydrate on the eye, causing discomfort, corneal staining, and potential epithelial damage. Mild to moderate dry eye may be managed with appropriate lens selection and supplemental tears, but severe cases are not suitable candidates.
Inability to Handle or Care for Lenses
Patients who cannot physically handle lenses due to severe dexterity limitations (arthritis, tremor, paralysis) or who lack the cognitive capacity to understand care instructions cannot safely wear contact lenses. Exceptions may exist when a caregiver can manage insertion, removal, and care.
Active Corneal Disease
Conditions such as acute corneal ulcer, severe corneal erosion, or active herpes simplex keratitis are absolute contraindications. The mechanical presence of a lens on a compromised cornea can worsen damage and impede recovery.
Relative Contraindications
These conditions require careful consideration, modified approaches, or close monitoring:
History of Giant Papillary Conjunctivitis (GPC)
Patients with a history of GPC are at higher risk for recurrence. However, they can often return to lens wear with modifications:
- Switch to daily disposable lenses to eliminate deposit buildup
- Change lens material (different polymer or surface treatment)
- Reduce wearing time
- Add mast cell stabilizer or antihistamine drops during adaptation
Poor Compliance
Poor compliance with care instructions, wearing schedules, or replacement intervals significantly increases the risk of serious complications, including microbial keratitis. Warning signs include:
- Sleeping in daily wear lenses
- Using water instead of contact lens solution
- Wearing lenses beyond the recommended replacement schedule
- Skipping regular follow-up appointments
- Ignoring symptoms and continuing to wear uncomfortable lenses
For non-compliant patients, daily disposable lenses minimize care-related risks since there is no cleaning or storage involved.
Allergies and Seasonal Conditions
Patients with chronic allergies may experience increased lens deposits, discomfort, and papillary reactions. Management strategies include:
- Daily disposable lenses during allergy season
- Preservative-free rewetting drops
- Antihistamine eye drops (instilled before lens insertion)
- Temporary discontinuation during severe flare-ups
Environmental Factors
Working in dusty, smoky, or chemical-laden environments increases the risk of debris getting trapped under lenses and exposure to irritants. These patients need careful counseling about protective eyewear and may benefit from daily disposable lenses that are discarded after each shift.
Medications Affecting Tear Film
Multiple medications can reduce tear production or alter tear quality (antihistamines, oral contraceptives, beta-blockers, isotretinoin). These do not necessarily prevent contact lens wear but may require supplemental tears, modified wearing schedules, or more frequent follow-up.
Systemic Conditions Requiring Caution
- Diabetes mellitus: Reduced corneal sensitivity, delayed healing, and increased infection risk. Fit with good-Dk materials, daily disposables preferred, and close monitoring
- Autoimmune diseases (Sjogren's syndrome, rheumatoid arthritis, lupus): Often associated with severe dry eye. Assess tear function thoroughly before fitting
- Immunocompromised patients: Increased infection risk. Meticulous hygiene and frequent follow-up are essential
- Pregnancy: Hormonal changes can alter corneal curvature, tear production, and refraction stability. Consider waiting until after delivery and breastfeeding for new fits
Age-Related Considerations
- Young children: Can wear contact lenses successfully for therapeutic purposes (aphakia, amblyopia) with caregiver management. Cosmetic fitting typically begins when the child can manage lens care independently (usually around age 10-12)
- Older adults: Reduced tear production, decreased corneal sensitivity, and dexterity challenges. Not contraindications per se, but require thoughtful lens selection and patient education
Key Takeaways
- Absolute contraindications include active infection, severe uncontrolled dry eye, inability to manage lenses, and active corneal disease
- Relative contraindications include GPC history, poor compliance, allergies, adverse environments, and drying medications
- Poor compliance is the greatest risk factor for contact lens-related microbial keratitis
- Daily disposable lenses reduce risk for many patients with relative contraindications
- Systemic conditions (diabetes, autoimmune disease, pregnancy) require caution but are not absolute barriers
- Clear documentation of risk factors and management plans protects both patient and practitioner