What is the treatment for photosensitivity?

Treatment for Photosensitivity

The most effective treatment for photosensitivity is a combination of sun avoidance, physical protection measures, and broad-spectrum sunscreens with SPF 30 or higher. 1

Types of Photosensitivity

Photosensitivity can be categorized into several types:

1. Drug-induced photosensitivity

   • Phototoxic reactions (direct cellular damage)
   • Photoallergic reactions (immune-mediated)
   • Common culprits: amiodarone, thiazide diuretics, tetracyclines, fluoroquinolones, NSAIDs 1

2. Primary photodermatoses

   • Polymorphic light eruption (PLE)
   • Chronic actinic dermatitis (CAD)
   • Solar urticaria
   • Actinic prurigo

3. Photosensitivity in systemic diseases

   • Lupus erythematosus
   • Porphyrias

4. Neurological photosensitivity

   • Photosensitive epilepsy 2, 3

Management Algorithm

Step 1: Sun Avoidance

• Limit exposure during peak UV hours (10 am - 4 pm)
• Avoid UV-reflective surfaces (sand, snow, water)
• For 24 hours after PUVA treatment, no sunlight exposure should occur 1
• No tanning beds should be used during treatment with photosensitizing medications 1

Step 2: Physical Protection

• Wear photoprotective clothing:
  • Broad-brimmed hats
  • Long sleeves and pants
  • UV-protective fabrics
• Use UV-blocking films on windows
• For specific photosensitive areas, consider:
  • Caps or visors pulled low on the forehead
  • Protective eyeglasses (may include photochromic or tinted lenses) 1

Step 3: Sunscreen Application

• Use broad-spectrum sunscreens (SPF ≥30) that protect against both UVA and UVB
• Apply sunscreen properly:
  • Use approximately 2 mg/cm² (much more than most people typically apply)
  • Reapply every 2 hours and after swimming/sweating
• For UVB protection specifically, zinc oxide and titanium dioxide are recommended 4
• For patients with photosensitivity disorders, sunscreen should be applied to all exposed areas 1

Step 4: Medication Management

• Identify and discontinue photosensitizing medications when possible
• If medication cannot be discontinued:
  • Take medication after UV exposure rather than before
  • Reduce UV exposure dose if starting a photosensitizing medication during phototherapy
  • For retinoids, decrease the dose of UV light to one-third to one-half 1

Step 5: Specific Treatments for Persistent Photosensitivity

For persistent or severe photosensitivity disorders:

1. Polymorphic Light Eruption (PLE):

   • Prophylactic phototherapy (PUVA, broadband UVB, or narrowband UVB) for several weeks during spring 5

2. Chronic Actinic Dermatitis (CAD):

   • Systemic immunosuppressants (cyclosporine, azathioprine)
   • PUVA therapy under specialist supervision 1, 5

3. Solar Urticaria:

   • Non-sedating antihistamines (fexofenadine, cetirizine)
   • Maintenance of a non-responsive state with controlled light exposure
   • In severe cases, plasmapheresis 5

4. Photosensitive Epilepsy:

   • Valproic acid (73-86% success rate)
   • Alternative options: levetiracetam, clobazam, lamotrigine 3

Special Considerations

For Drug-Induced Photosensitivity

• Monitor for specific clinical patterns:
  • Phototoxicity: immediate exaggerated sunburn reaction
  • Photoallergy: delayed eczematous reaction
  • Other presentations: hyperpigmentation, pseudoporphyria, photo-onycholysis 6

For Patients on PUVA Therapy

• Shield areas of recent skin cancer or surgical scars
• Shield face with towel or bag if no facial lesions are present
• For 24 hours after PUVA, use protective clothing and sunscreen (SPF ≥30) on exposed areas
• Regular evaluation by dermatologist during PUVA and annual skin examinations 1

For Children with Photosensitivity

• Consider reversing polarity (white print on black background) on computers for those with photophobia
• Ensure protective eyewear is used during school activities
• Modify sports and physical education to ensure safety and participation 1

Common Pitfalls to Avoid

1. Inadequate sunscreen application: Most people apply only 25% of the recommended dose, severely compromising protection 4

2. Ignoring drug interactions: Psoralens can interfere with liver metabolism, potentially increasing serum levels of warfarin, anticholinergics, antipsychotics, NSAIDs, theophylline, and caffeine 1

3. Overlooking dietary triggers: Enhancement of PUVA phototoxicity has been reported after ingestion of celery, vegetable broths, and Rutaceae extracts 1

4. Failing to recognize photosensitivity disorders: These can be disabling and difficult to diagnose, requiring specialist assessment 5

By following this comprehensive approach to managing photosensitivity, patients can significantly reduce their symptoms and improve their quality of life while minimizing the risk of complications.