Efficacy and Safety of Different Concentrations of Intralesional Triamcinolone Acetonide in Alopecia Areata: A Prospective, Randomized, Double-blind, Placebo-controlled Study

Alopecia areata (AA) is an autoimmune disease characterized by nonscarring hair loss with varying degree of severity. It most commonly involves scalp hair. It was estimated to occur in 0.1% to 0.2% of the general population in the united states. Patchy hair loss is the most common pattern seen in AA.

There are many treatment modalities available for AA, however, none of them cure the disease. Given the potential for spontaneous recovery in AA, studies assessing the efficacy of a certain therapeutic modality must be conducted in a controlled fashion. Treatment with intralesional corticosteroids (ILCSs) is considered the first-line therapy in adult patients with less than 50% scalp involvement. Use of ILCSs in AA was first reported by Kalkoff in 1958 using hydrocortisone. There are no published randomized controlled trials on the use of ILCSs in AA. Triamcinolone acetonide (TA) is the most commonly used form of ILCSs. It is characterized by low solubility, being slowly absorbed from the injection site, prompting maximal local action, limiting diffusion and spread through tissue, and not giving rise to systemic side effects if used in therapeutic doses. Use of intralesional (IL) TA in AA was first described by Orentreich et al. in 1960. IL TA is usually used in concentrations ranging from 2.5 to 10 mg/ml. Injections (0.1 ml per injection site) are given intradermally every 4 to 6 weeks. Abell and Munro used IL TA in the treatment of AA of varying degree of severity in 84 patients. The concentration used was 5 mg/ml and injections were given three times every 1 to 2 weeks. Fifteen patients received injections with isotonic normal saline as a control. Seventy one percent of patients with limited AA have shown evidence of regrowth compared to only 7% of patients in the control group. They also noticed that IL TA injections failed in all patients with rapidly progressive disease.

Side effects of IL TA include pain at the injection site, mild bleeding, transient atrophy and telangiectasia, hypopigmentation, hyperpigmentation. Infection is uncommon but caution over bony prominences is recommended. Adrenal suppression is rare when using lower doses. It has been reported in one patient who received a total dose of 22.5 mg in one session and the serum cortisol level normalized after 3 days. It has been shown that TA at a dose of 20 mg does not result in adrenal suppression. Hypersensitivity reactions to TA or the vehicle carboxymethylcellulose are extremely rare.

To our knowledge, there are no prospective studies comparing the efficacy and safety of different concentrations of IL TA in the treatment of AA. Helfman compared the therapeutic effect of different concentrations of IL TA in the treatment of different dermatoses. He included only one patient with localized AA. He injected TA using three different concentrations (2.5, 5, and 10 mg) and a diluent as placebo. Injections were done in 4 different quadrants within the same patch. He noticed that there was an equivalent degree of hair regrowth in the three sites injected with TA, and no regrowth in the site injected with the diluent.

Study Objectives