What are the effects of chronic use of eyedrops?

Effects of Chronic Use of Eyedrops

Chronic use of eyedrops can lead to significant ocular surface changes, medication-specific side effects, and systemic complications that may impact morbidity, mortality, and quality of life, requiring careful monitoring and management strategies.

Local Effects on Ocular Surface

Preservative-Related Effects

• Benzalkonium chloride (BAK) and other preservatives in eyedrops can cause:
  • Ocular surface inflammation
  • Tear film instability
  • Reduced tear production
  • Epithelial damage
  • Increased risk of allergic contact dermatitis 1
  • Preservative-free formulations are recommended for long-term use, especially in patients with pre-existing ocular surface disease 1

Medication-Specific Effects

Prostaglandin Analogs (e.g., Latanoprost)

• Eyelid skin darkening (may be reversible upon discontinuation) 2
• Changes to eyelashes including:
  • Increased length, thickness, and pigmentation
  • Increased number of lashes
  • Misdirected growth of eyelashes 2
• Increased iris pigmentation (may be permanent) 2

Corticosteroid Eyedrops

• Should be limited to short-term use (maximum 8 weeks) 1
• Prolonged use risks:
  • Cataract formation
  • Intraocular pressure elevation
  • Increased susceptibility to infections 1

Antihistamine/Vasoconstrictor Agents

• Chronic use can lead to rebound vasodilation upon discontinuation 1
• May worsen dry eye symptoms with long-term use 1

Systemic Absorption and Effects

Risk of Systemic Complications

• Inadvertent systemic absorption can occur, especially with:
  • Improper administration technique
  • Lack of nasolacrimal occlusion
  • Multiple drop administration 3
• Beta-blocker eyedrops (e.g., timolol) can cause:
  • Lightheadedness
  • Dyspnea
  • Chest pressure
  • Faintness
  • Exacerbation of heart failure 3

Minimizing Systemic Absorption

• Digital pressure can be applied over the lacrimal sac and puncta after administration 4
• Allow at least 5 minutes between different eyedrop medications 2
• Proper administration technique is crucial to minimize systemic effects 1

Adherence and Administration Challenges

Adherence Issues

• Studies indicate poor adherence to eyedrop therapy, even with instruction and monitoring 1
• Nearly 45% of glaucoma patients take fewer than 75% of prescribed doses 1
• Fixed combinations of medications may improve adherence by reducing the number of drops required 1

Administration Difficulties

• Proper instillation is difficult for many patients 1
• Ability to self-administer worsens with:
  • Aging
  • Comorbidities
  • Disease progression 1
• Nearly half (43-49%) of patients with glaucoma or dry eye disease have at least one comorbid condition that could affect eyedrop self-administration 5
• Patients with multiple conditions that may impair administration have significantly higher odds of requiring eyedrop therapy 5

Management Strategies for Long-Term Use

Improving Administration and Adherence

• Provide repeated instruction and counseling about proper techniques 1
• Create clearly written medication regimens 1
• Consider smartphone reminders and follow-up calls 1
• Link eyedrop administration to activities of daily living 1

Alternative Delivery Systems

• Consider alternative drug delivery systems for patients with adherence issues:
  • Punctal plugs
  • Fornix rings
  • Contact lenses
  • Subconjunctival injections/devices
  • Intracameral delivery systems 1
• Bimatoprost intracameral implant has been FDA-approved for glaucoma patients with administration difficulties 1

Special Considerations

Contact Lens Wearers

• Contact lenses should be removed prior to eyedrop administration 2
• Lenses may be reinserted 15 minutes after administration 2
• Preservatives in eyedrops may be absorbed by contact lenses 2

Multiple Medication Management

• If more than one topical ophthalmic drug is being used, administer at least five minutes apart 2
• Eye drops must be instilled before applying eye ointment, as ointment affects drop absorption 6

When to Consider Alternative Therapies

• Consider alternative therapies when:
  • Patient experiences significant loss of quality of life due to eyedrop side effects 1
  • Prolonged corticosteroid therapy (>8 weeks) is required 1
  • Patient has physical or cognitive limitations affecting proper administration 5
  • Significant risk exists that visual acuity may be reduced due to medication side effects 1

By understanding these effects and implementing appropriate management strategies, healthcare providers can help minimize the negative impacts of chronic eyedrop use while maximizing therapeutic benefits.