Intralesional Kenalog Dosing for Multiple Lesions
With a 40 mg vial of Kenalog (triamcinolone acetonide), you can inject 16 lesions using the standard 2.5 mg/mL concentration at 0.05 mL per lesion, or 8 lesions if using 0.1 mL per lesion.
Standard Concentration and Volume
The most commonly used concentration for intralesional triamcinolone in acne and inflammatory lesions is 2.5 mg/mL, reported by 52.5% of dermatologists surveyed 1. At this concentration:
- 0.05 mL per lesion (the most frequently used volume, reported by 42.3% of practitioners) delivers 0.125 mg per lesion 1
- A 40 mg vial diluted to 2.5 mg/mL yields 16 mL total volume
- This allows treatment of approximately 320 lesions at 0.05 mL each or 160 lesions at 0.1 mL each
Practical Calculation Based on Dose Per Lesion
However, the more clinically relevant calculation is based on total triamcinolone dose distributed across lesions:
- If injecting 2.5 mg per lesion (a common approach for larger nodules): 16 lesions maximum from a 40 mg vial
- If injecting 5 mg per lesion (for very large or resistant lesions): 8 lesions maximum
- If injecting 1.25 mg per lesion (for smaller lesions): 32 lesions maximum
Injection Technique Considerations
- Depth: 61.6% of practitioners inject into the center of the lesion 1
- Volume per site: Most commonly 0.05 mL, though volumes range from 0.03-0.1 mL depending on lesion size 1
- Adverse events: Atrophy and hypopigmentation occur in less than 1% of patients but can last over 6 months when they do occur 1
Safety Counseling
50.5% of dermatologists counsel patients about potential hypopigmentation and atrophy before every injection 1. This is critical given that while adverse events are rare (occurring in <1% of patients), they are long-lasting when they occur 1.
Clinical Caveat
The American Academy of Dermatology notes that triamcinolone works by suppressing inflammatory responses and has no antifungal properties 2. Ensure proper diagnosis before injection, as the concentration and volume should be adjusted based on lesion size, location, and patient skin type to minimize atrophy risk.