Intralesional Triamcinolone Injection Technique and Depth
Inject triamcinolone acetonide into the dermis at the upper subcutis level (just beneath the dermis) using a 25-27 gauge needle, with volumes of 0.05-0.1 mL per injection site to produce blanching of the lesion and 1-2 mm of surrounding skin. 1, 2
Injection Depth and Anatomical Target
The corticosteroid must be injected just beneath the dermis in the upper subcutis 2, 3. This is critical because:
- Dermal injection is essential for efficacy - subcutaneous injection would be innocuous but ineffective 4
- Initial dermal injection may meet with resistance, which tends to decrease with subsequent sessions 4
- Atrophy of subcutaneous fat occurs if injection is not properly given 5
Needle Selection and Technique
Needle Specifications
- Use 25-27 gauge needles for intralesional injections 4
- Smaller gauge needles (25G) are preferred for keloids and dense lesions 6
- For systemic intramuscular injections, minimum 1½ inch needle length is required 5
Injection Technique
Step-by-step approach:
Cleanse the lesion and surrounding skin (Betadine or soap and water) 4
Approach at right angle initially, then infiltrate in a V-shaped pattern 4
Inject under pressure as the needle is advanced 4
Continue until blanching is seen - the entire lesion and 1-2 mm of surrounding normal-appearing skin must be infiltrated 4
Volume per site: 0.05-0.1 mL injection produces a tuft of response about 0.5 cm in diameter 2, 3
Concentration and Dosing by Indication
For Acne (Nodular/Cystic)
- Concentration: 10 mg/mL triamcinolone acetonide, may be diluted to 5 or 3.3 mg/mL with sterile normal saline 1
- Volume: Determined by lesion size, 0.2-5 mL in up to 4-5 injection sites 4
- Estimated dose: approximately 0.1 mL/cm² 4
For Alopecia Areata
- Concentration: Hydrocortisone acetate 25 mg/mL or triamcinolone acetonide 5-10 mg/mL 2, 3
- Volume: 0.05-0.1 mL per injection site 2, 3
For Infantile Hemangiomas
- Use triamcinolone and/or betamethasone for focal, bulky lesions during proliferation 7
- Reserved for relatively small, well-localized lesions where proliferation threatens anatomic landmarks
For Keloids/Hypertrophic Scars
- Concentration: Triamcinolone acetonide 40 mg/mL 1
Critical Anatomic Contraindications
Do NOT inject in these locations due to vascular compromise risk:
- Fingers
- Nose
- Ears
- Eyelids
- Near the lips 4
Special warning for upper eyelid: Rare reports of central retinal artery embolization exist, likely related to high injection pressures and/or volumes 7
Common Pitfalls and How to Avoid Them
Local Complications from Improper Technique
- Atrophy, pigmentary changes, telangiectasias result from local overdose 1
- Fat and/or dermal atrophy occurs with improper depth 7
- Subcutaneous fat atrophy if injection not properly given into gluteal muscle for systemic use 5
Prevention Strategies
- Use lower concentrations and volumes to minimize local adverse events 8
- Ensure strict aseptic technique 5
- Avoid injecting into tendon substance - inject into tendon sheath for tenosynovitis 5
- For epicondylitis, infiltrate into area of greatest tenderness 5
Pain Management
The procedure is painful; local anesthesia should be given in advance (such as EMLA cream - lidocaine plus prilocaine) 4. Young children may need general anesthesia 4. The main limitation to multiple injections is patient discomfort 2, 3.