The steroid medication begins to take effect in one to two days at which point you should start to see some benefit. The steroid effect will continue to increase with the peak effect occurs at about two weeks. Thereafter, the effect will stabilize and should last several weeks to months. Typically, the pain relief experienced from this procedure lasts 3-6 months, but there is significant variability from patient to patient and from one procedure to another. If and when the pain starts to return, this procedure can be repeated to try and attain some pain relief once again. Keep in mind that this injection may work very well for pain certain areas but may not help with others. This is normal. Areas of pain that do not respond may need other treatments, which you can discuss with your doctor.
A recent randomized, double-blind, placebo-controlled trial studied the long-term safety and efficacy of treatment of knee osteoarthritis with repeated steroid injections. 6 These investigators studied 66 patients aged 40 to 80 years recruited from rheumatology clinics. One half (n=33) received injections of triamcinolone acetonide 40 mg, and the other half received saline injections every 3 months for 2 years. At 1- and 2-year interval follow-ups, no statistically significant difference was seen between the 2 groups in loss of joint space and no progression of degenerative disease, as demonstrated by measurements of joint space widths by standardized fluoroscopically guided radiographs. Although the primary outcome measure of this study was to assess radiologic joint space narrowing with repeated injections, knee pain and stiffness appeared to improve after 2 years, although these results were not well quantified.
Intramuscular Injection: Provides an extended duration of therapeutic effect and fewer side effects of the kind associated with oral corticosteroid therapy, particularly gastro-intestinal reactions such as peptic ulceration. Studies indicate that, following a single intramuscular dose of 80 mg triamcinolone acetonide, adrenal suppression occurs within 24 - 48 hours and then gradually returns to normal, usually in approximately three weeks. This finding correlates closely with the extended duration of therapeutic action of triamcinolone acetonide.