Is intralesional Kenalog (triamcinolone acetonide) effective for hypertrophic or keloid‑like surgical scars in an adult 4–6 weeks after full epithelialization?

Is Kenalog Effective for Surgical Scars?

Yes, intralesional triamcinolone acetonide (Kenalog) is effective for treating hypertrophic and keloid surgical scars, with success rates of 64-95% for flattening lesions and 72-91% for symptomatic relief, though it works best when combined with other modalities or used for prevention rather than as monotherapy for established pathologic scars. 1, 2, 3

Evidence for Effectiveness

Established Hypertrophic and Keloid Scars

• Intralesional triamcinolone acetonide provides complete flattening in 64% of keloids and hypertrophic scars when used alone, with 72% achieving symptomatic relief (pain, pruritus reduction). 3

• A systematic review and meta-analysis demonstrates that TAC improves vascularity and pliability in the short term compared to verapamil, though 5-fluorouracil (5-FU) or combination therapy (TAC + 5-FU) shows superior results for medium- and long-term treatment of scar height, pliability, and pigmentation. 1

• For recurrent or complicated keloids and hypertrophic scars, surgical excision combined with intraoperative TAC injection followed by serial postoperative injections achieves 91.9% success for keloids and 95.2% success for hypertrophic scars at 30-month follow-up. 2

Normal Surgical Scars (Prevention)

• Low-dose triamcinolone acetonide injected intraoperatively on normal surgical suture lines significantly improves scar maturation, reducing vascularity, pigmentation, and height while improving overall appearance compared to untreated scars. 4

• This preventive approach shows significant differences in Vancouver Scar Scale scores for vascularity, pigmentation, and total score, as well as Stony Brook Scar Evaluation Scale scores for height, color, and overall appearance. 4

Optimal Dosing and Administration

For Established Pathologic Scars

• The American Academy of Dermatology recommends triamcinolone acetonide at concentrations of 5-10 mg/mL for intralesional injection, using the minimum effective amount to control symptoms. 5

• Higher concentrations (20-40 mg/mL) increase efficacy but significantly raise the risk of skin atrophy and telangiectasia compared to lower concentrations or alternative agents like 5-FU. 1

• For optimal results with recurrent lesions: inject intraoperatively during excision, then repeat weekly for 2-5 weeks until symptomatic relief, followed by monthly injections for 4-6 months. 2

For Normal Surgical Scars

• Low-dose triamcinolone acetonide is effective for scar maturation, with no significant difference found between varying doses, suggesting lower concentrations minimize adverse effects while maintaining efficacy. 4

Critical Limitations and Adverse Effects

Side Effect Profile

• Skin atrophy at injection sites is the most consistent adverse effect of intralesional triamcinolone therapy, particularly at higher concentrations. 5, 6, 1

• Telangiectasia occurs more frequently with TAC (especially at 20-40 mg/mL) compared to 5-FU, 5-FU+TAC combination, or bleomycin. 1

• Hypopigmentation, pigmentary changes, and folliculitis are common side effects that should be discussed with patients. 5, 6

Risk Mitigation Strategies

• Apply sparingly to skin folds and intertriginous areas to minimize atrophy risk, and use the lowest effective concentration and volume. 5, 6

• Consider gradual reduction in treatment frequency after clinical improvement, with twice-weekly application for maintenance therapy. 5

Clinical Algorithm for Surgical Scars

Timing Considerations (4-6 Weeks Post-Epithelialization)

1. For normal-appearing surgical scars with risk factors for hypertrophic scarring or keloid formation: Consider prophylactic low-dose intralesional TAC to improve scar maturation and prevent pathologic scar development. 4

2. For early hypertrophic changes: Initiate intralesional TAC (5-10 mg/mL) with serial injections every 4-6 weeks, monitoring for flattening and symptomatic improvement. 5, 3

3. For established keloids or resistant hypertrophic scars: Consider combination therapy (TAC + 5-FU) or surgical excision with intraoperative and postoperative TAC protocol for superior long-term outcomes. 1, 2

Important Caveats

• TAC shows variable efficacy between individuals, and while effective for short-term improvement, combination therapies or alternatives like 5-FU may produce superior medium- and long-term results for scar height reduction. 1

• The recent withdrawal of Kenalog® licensing in some regions (UK) has raised concerns about treatment availability, though the therapeutic mechanism remains valid with alternative triamcinolone formulations. 7

• Intralesional steroids should never be used in periocular areas due to rare but devastating risk of central retinal artery embolization, which can cause permanent vision loss. 8, 6