Kenacort (Triamcinolone) Injection Dosing and Administration
For intra-articular injection in inflammatory arthritis, triamcinolone hexacetonide is strongly preferred over triamcinolone acetonide (Kenacort-40) due to superior duration of response, though triamcinolone acetonide remains acceptable when hexacetonide is unavailable. 1
Preferred Formulation and Rationale
Triamcinolone hexacetonide provides substantially better efficacy than triamcinolone acetonide, with response rates of 77% vs 39% at 24 months in knee arthritis 2. The American College of Rheumatology strongly recommends triamcinolone hexacetonide as the preferred agent for intra-articular glucocorticoid injections in juvenile idiopathic arthritis, based on randomized trials showing more durable clinical responses 1. This superiority extends to adult rheumatoid arthritis, where triamcinolone hexacetonide demonstrates faster pain relief and longer duration of action compared to other corticosteroid preparations 3, 2.
Critical Caveat on Availability
Triamcinolone hexacetonide has been unavailable in the US for several years, though the FDA recently allowed importation of specific formulations for joint injections in JIA patients 1. When hexacetonide is unavailable, triamcinolone acetonide (Kenacort-40) remains an acceptable alternative 1.
Dosing by Joint Size
Intra-articular Administration
For smaller joints: 2.5-5 mg per injection 4
For larger joints (knee, hip, shoulder): 5-15 mg per injection, with doses up to 40 mg for larger areas having been sufficient 4
Maximum total dose: Single injections into multiple joints up to 80 mg total have been administered 4
Systemic Intramuscular Administration
Initial dose: 60 mg injected deeply into the gluteal muscle 4
Dosage range: Usually adjusted within 40-80 mg depending on patient response and duration of relief, though some patients may be controlled on doses as low as 20 mg 4
For hay fever/pollen asthma: Single injection of 40-100 mg may provide remission throughout the pollen season 4
Administration Technique
Mandatory Technical Requirements
Strict aseptic technique is mandatory 4. The vial must be shaken before use to ensure uniform suspension, and the suspension should be inspected for clumping or granular appearance (agglomeration) 4. An agglomerated product should be discarded 4.
After withdrawal, inject without delay to prevent settling in the syringe 4. For intramuscular systemic therapy, injection must be made deeply into the gluteal muscle using a minimum needle length of 1½ inches for adults (longer needles may be required in obese patients) 4.
Joint-Specific Considerations
For knee and hand joints: Ultrasound guidance is not required but may be helpful 1
For hip joints: Ultrasound guidance is strongly recommended to ensure accurate drug delivery 1
Synovial fluid management: If excessive synovial fluid is present, some (but not all) should be aspirated to aid pain relief and prevent undue dilution of the steroid 4
Clinical Context and Indications
Osteoarthritis
Intra-articular glucocorticoid injections are strongly recommended for knee and hip OA, and conditionally recommended for hand OA 1. These injections demonstrate short-term efficacy and are preferred over other intra-articular preparations including hyaluronic acid 1.
Rheumatoid Arthritis
Intra-articular glucocorticoids are strongly recommended as part of initial therapy for active oligoarthritis in juvenile idiopathic arthritis 1. For adult RA, intra-articular injections provide rapid and long-term reduction of knee pain and swelling 5.
Comparative efficacy: Triamcinolone acetonide (40 mg) provides similar pain relief to dexamethasone (8 mg) for knee arthritis in RA, with average pain reduction occurring within 2-3 days and relapse rates of approximately 6-10% at 6 months 5.
Post-Injection Management and Complications
Expected Post-Injection Flare
Most post-injection flares resolve within 24-72 hours with conservative management 6. Pain and stiffness should show improvement by day 5-7, with therapeutic benefit typically becoming apparent at 1-2 weeks after the initial flare resolves 6.
Conservative management includes:
- NSAIDs for pain and inflammation as primary treatment 6
- Rest and activity modification to avoid weight-bearing activities 6
- Ice application for symptomatic relief 6
Warning Signs Requiring Further Evaluation
Examine for warmth, erythema, and effusion to differentiate post-injection flare from septic arthritis, with marked warmth and erythema favoring infection 6. Consider joint aspiration if significant effusion is present or infection cannot be clinically excluded, with synovial fluid analysis (cell count, Gram stain, culture) being essential 6.
If symptoms persist beyond 1 week, consider joint aspiration to rule out delayed infection and reassess the diagnosis 6.
Severe Crystal-Induced Reactions
Rare but severe postinjection flares can occur, mimicking septic arthritis with acute onset of intense pain, swelling, and inability to ambulate within hours of injection 7. These represent acute crystal-induced inflammatory responses confirmed by triamcinolone acetonide crystals in synovial aspirate viewed by polarized light microscopy 7. The synovial fluid may appear "butterscotch"-colored, and cultures will be negative 7.
Frequency and Repeat Injections
A single local injection is frequently sufficient, but several injections may be needed for adequate symptom relief 4. The FDA label emphasizes that dosage requirements are variable and must be individualized based on the disease under treatment and patient response 4.
Important Limitations
Recent reports suggest that specific steroid preparations or certain frequencies of injections may contribute to cartilage loss, though the clinical significance remains uncertain as cartilage changes were not associated with worsening pain, function, or other radiographic features 1. Intra-articular injections may not be appropriate for large numbers of joints or joints injected multiple times; escalation of systemic therapy may be preferred in these situations 1.
Monitoring Requirements
For patients with diabetes: Closely monitor blood glucose for two weeks following periarticular or soft tissue steroid injection 8.
Facial flushing occurring 2-3 days post-injection is the most common side effect and is typically no worse than a nuisance 3. Complications from steroid injections are rare overall 8.