Hair regrowth with topical triiodothyronine ointment in patients with alopecia areata: a double-blind, randomized pilot clinical trial of efficacy.

BACKGROUND

Thyroid hormone receptors are expressed in hair follicles and it is known that thyroid hormones can have a positive effect on hair growth, i.e. process which is disrupted in alopecia areata.

OBJECTIVES

The aim of this study was to determine the efficacy of topical triiodothyronine in patients with patchy alopecia areata.

METHODS

Ten patients with patchy alopecia areata were treated with triiodothyronine and placebo applied twice daily to either of two bilaterally symmetrical patches for 12 weeks. The two sides were randomly assigned following simple randomization procedure to one of the two treatment groups. The patients and the investigator were blinded to the content of the tubes. Hair regrowth was evaluated every 4 weeks. Blood samples for measurements of complete blood count along with thyroid function (T3, T4 and TSH) and liver function tests were taken at the baseline and at the end of study.

RESULTS

After 12 weeks of treatment, there was no statistically significant difference between the outcome in terms of reduction of the patch size and hair regrowth. No adverse effects were noted.

CONCLUSION

Triiodothyronine in the studied dosage and formulation was safe but not more effective than placebo. However, newer thyroid hormone analogues might be more effective and evaluating their effects probably warrants further consideration.