Prophylactic Intralesional Triamcinolone After Incision for Keloid Prevention
For patients at risk of keloid formation after an incision, inject triamcinolone acetonide 10 mg/mL (diluted from the standard 40 mg/mL concentration) subdermally along both edges of the wound immediately after closure, using approximately 1 mL per ampule along each edge of the incision. 1
Evidence-Based Dosing Protocol
The most relevant study for your specific question involves injecting triamcinolone at the time of wound closure to prevent keloid recurrence:
- Concentration: Use 10 mg/mL triamcinolone acetonide (diluted from 40 mg/mL stock) 1
- Timing: Inject immediately after wound closure, before skin closure is complete 1
- Technique: Inject subdermally (just beneath the dermis in the upper subcutis) along the entire length of both the upper and lower edges of the skin incision 1, 2
- Volume: Use one 1 mL ampule (10 mg) along the upper edge and one 1 mL ampule (10 mg) along the lower edge of the incision 1
- Needle size: Use a 25-gauge needle for injection 1
Dilution Instructions
Yes, dilution is required for prophylactic use:
- The standard keloid treatment concentration is 40 mg/mL 3, 2
- For prophylactic injection at wound closure, dilute to 10 mg/mL using sterile normal saline 1
- This represents a 1:4 dilution (1 part triamcinolone 40 mg/mL + 3 parts sterile saline = 10 mg/mL final concentration)
Rationale for Lower Concentration
The lower concentration (10 mg/mL) for prophylactic use versus established keloid treatment (40 mg/mL) makes clinical sense because:
- You're treating normal tissue at risk rather than established pathologic scar tissue 1
- Lower concentrations minimize the risk of skin atrophy, pigmentary changes, and telangiectasias in fresh surgical wounds 3, 2
- The American Academy of Dermatology specifically recommends lower concentrations (5-10 mg/mL) for facial areas or sites at higher risk for atrophy 2
Expected Outcomes and Limitations
Important caveats about this approach:
- Even with established keloid treatment using higher concentrations (40 mg/mL), recurrence rates are 33% at 1 year and 50% at 5 years 4
- The prophylactic protocol at wound closure showed promising results in the trial design, but long-term efficacy data are still being collected 1
- For established keloids requiring treatment, the standard concentration is 40 mg/mL, repeated every 3-4 weeks until flattening occurs 3, 2
Critical Technical Points
Injection depth is crucial:
- Target the upper subcutis just beneath the dermis, NOT into the dermis itself or deeper subcutaneous fat 2
- Avoid injecting into tendon substance if near joints 2
- The goal is to create a depot effect along the wound edges where keloid formation typically begins 1
Contraindications to Avoid
Do not inject triamcinolone if: