A Closer Look at Triamcinolone Acetonide
Steroid injections are commonly used in dermatology and essential treatments offered by the hair specialist. Triamcinolone acetonide (TAC) remains one of the most common steroids used for treatment of alopecia areata, traction alopecia as well as scarring alopecias. Doses of TAC range from 2.5 to 40 mg per mL although doses of 2.5 mg/mL to 10 mg/mL are by far the most common. I frequently use 2.5, 3.3 and 5 mg/mL in my practice and limit steroids to no more than 20 mg total dose every 4-6 weeks.
Triamcinolone acetonide is a “suspension” meaning that it does not actually dissolve. In the photo, particles of TAC can be seen on the bottom of the syringe rather than dissolved in the solution. TAC particles range in size from 0.5 to 1000 micrometers. About 1/3 of particles are between 0 and 10 um, another 1/3 are between 10-20 um and the remaining 1/3 are greater than 20 um. Rarely particles can be as large as 1000 um but this occurs in less than 1% of all particles.
When preparing TAC solutions, one should ensure the steroid is well mixed before injection. If there is any difficulty injecting through a 30 G needle one should stop and ensure the solution is mixed well.
Benzon HT et al. Comparison of the particle sizes of different steroids and the effect of dilution: a review of the relative neurotoxicities of the steroids.
Benzon HT, et al. Anesthesiology. 2007.
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887