Can methotrexate (MTX) cause eye burning?

Methotrexate and Eye Burning: Recognition and Management

Yes, methotrexate can cause eye burning as a recognized side effect, which may be related to the drug's presence in tear film and potential ocular surface irritation. 1

Mechanism and Presentation

• Methotrexate can be secreted in tear film at concentrations equivalent to plasma levels, potentially causing ocular irritation symptoms including burning, pruritus, and dry eye sensation 1
• Acidic lacrimal secretions (pH 6.5) may contribute to decreased solubility of methotrexate in the conjunctival sac, exacerbating symptoms 1
• Ocular irritation symptoms typically occur 2-7 days after methotrexate administration 1

Risk Factors and Monitoring

• Patients on higher doses of methotrexate are more likely to experience ocular side effects 1, 2
• Patients with decreased tear production may be more susceptible to methotrexate-related eye irritation 1
• Regular ophthalmic monitoring should be considered for patients reporting eye symptoms while on methotrexate therapy 2

Management Approaches

Prevention Strategies

• Folic acid supplementation (1-5 mg/day) is recommended for all patients on methotrexate to reduce overall side effects, which may help mitigate ocular symptoms 3
• Adequate hydration is recommended to improve methotrexate elimination and potentially reduce side effects 4
• Consider subcutaneous administration of methotrexate instead of oral administration, as this may improve bioavailability and reduce side effects 3

Treatment Options

• If eye burning occurs:

  1. Consider temporary dose reduction of methotrexate if symptoms are bothersome 5
  2. Use artificial tears for symptomatic relief of dry eye/burning sensation 1
  3. Ensure proper folic acid supplementation (1 mg/day for 6 days/week) 3
  4. Monitor for other signs of methotrexate toxicity that may require intervention 5

• For severe or persistent symptoms:

  1. Consider temporary discontinuation of methotrexate 5
  2. Ophthalmology consultation to rule out other causes of eye burning 2
  3. Evaluate for more serious ocular complications like optic neuropathy 6

Important Considerations

• Eye burning is generally a reversible side effect that resolves with dose reduction or discontinuation of methotrexate 1, 2
• Distinguish between simple irritation and more serious ocular complications like optic neuropathy, which has been reported with methotrexate (though rare) 6
• Patients should be advised to report eye symptoms promptly as part of the pre-treatment counseling about potential side effects 5
• Regular monitoring of complete blood count, liver function, and renal function is essential for all patients on methotrexate, regardless of ocular symptoms 5

Clinical Pearls

• Eye burning symptoms typically appear within days after methotrexate administration and may be recurrent with subsequent doses 1
• The therapeutic benefit of methotrexate may take 3-12 weeks to become apparent, so early side effects like eye burning should be managed supportively when possible rather than immediately discontinuing therapy 5
• Patients with pre-existing dry eye syndrome may be more susceptible to methotrexate-related ocular irritation 1
• NSAIDs used concurrently with methotrexate can increase methotrexate levels and potentially worsen side effects, including ocular symptoms 4