What is the recommended dosing for intralesional (within the lesion) scalp steroid injections, specifically triamcinolone acetonide, for treating alopecia areata?

Intralesional Triamcinolone Acetonide Dosing for Scalp Alopecia Areata

For intralesional scalp steroid injections to treat alopecia areata, triamcinolone acetonide should be used at a concentration of 5-10 mg/mL, with 0.05-0.1 mL injected per site just beneath the dermis in the upper subcutis. 1

Recommended Dosing Protocol

Concentration

• Triamcinolone acetonide: 5-10 mg/mL
  • Both concentrations show similar efficacy and safety profiles 2
  • Lower concentration (5 mg/mL) may be preferred to minimize side effects while maintaining efficacy

Administration Technique

• Injection depth: Just beneath the dermis in the upper subcutis
• Volume per injection site: 0.05-0.1 mL
• Coverage: Each injection produces a tuft of hair growth approximately 0.5 cm in diameter
• Multiple injections may be given, limited primarily by patient discomfort 1

Treatment Schedule

• Frequency: Monthly injections 1, 3
• Duration: Continue until satisfactory response is achieved
  • Initial regrowth typically begins at approximately 2.4 months
  • Cosmetically acceptable regrowth often achieved by 4 months 3
  • Effect typically lasts about 9 months 1

Patient Selection

This treatment is most appropriate for:

• Patchy hair loss of limited extent
• Fewer than five patches of < 3 cm in diameter
• Cosmetically sensitive sites such as eyebrows 1
• Patients with less than 50% scalp involvement (traditional recommendation)
  • However, can be effective in selected patients with more extensive involvement (50-99%) 4

Expected Outcomes

• 62% of patients achieve full regrowth with monthly injections 1
• Response is better in patients with:
  • Fewer patches
  • Smaller patch size
  • Presence of exclamation mark hairs
  • Positive hair pull test 4
  • Disease duration less than 6 months 2

Monitoring

• Assess response after 6-12 weeks of treatment 3
• Dermoscopic evaluation can detect early response as soon as 4 weeks after initiating treatment 5
• Monitor for side effects at each visit

Potential Side Effects

• Skin atrophy at injection sites (most common)
• Mild pain during injection
• Folliculitis (can be minimized with proper technique)
• These side effects are typically reversible 4

Alternative Administration Methods

• Needleless devices (e.g., Dermajet) can be used as an alternative to traditional needle injection
  • 62% of patients showed regrowth at 12 weeks after three injections using this method 1

Cautions

• Poor prognostic factors include:
  • Childhood onset
  • Ophiasis pattern
  • Extensive hair loss
  • Long disease duration
  • Associated nail changes 3
• Recurrence rate is approximately 45% after 1-3 years 2

Intralesional triamcinolone acetonide remains the first-line treatment for limited patchy alopecia areata, with a favorable efficacy and safety profile when administered according to these guidelines.