Topical methimazole as a new treatment for postinflammatory hyperpigmentation: report of the first case.
We have previously shown that the peroxidase inhibitor methimazole (1-methyl-2-mercapto imidazole; MMI) is a noncytotoxic inhibitor of melanin production in cultured B16 melanocytes. It was further demonstrated that the topical application of 5% MMI on brown guinea pig skin for 6 weeks causes a significant reduction in the amount of epidermal melanin, resulting in visually recognizable cutaneous depigmentation. Herein, we report a 27-year-old male with postinflammatory hyperpigmentation (due to acid burn), successfully treated with topical MMI as a new skin depigmenting agent. Topical 5% MMI caused a moderate to marked improvement of the hyperpigmented lesions within 6 weeks of once-daily application. Topical MMI was well tolerated by the patient and did not affect the level of serum thyroid hormones (free thyroxin, free triiodothyronine and the thyroid-stimulating hormone). Unlike most known depigmenting agents, such as hydroquinone and kojic acid, MMI is a noncytotoxic, nonmutagenic compound, and it is possible that MMI could serve as a novel agent for the treatment of hyperpigmentary disorders in human.
Kasraee
Behrooz
B
Jahrom School of Medical Sciences, Jahrom, Iran. kasraeeb@sums.ac.ir
Handjani
Farhad
F
Parhizgar
Amin
A
Omrani
Gholamhosein R
GR
Fallahi
Mohammad Reza
MR
Amini
Mitra
M
Nikbakhsh
Mohammad
M
Tran
Christian
C
Hügin
Ambros
A
Sorg
Olivier
O
Saurat
Jean-Hilaire
JH
D000279:Administration, Cutaneous; D000328:Adult; D002057:Burns, Chemical / Q000150:complications; D003879:Dermatologic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D005148:Facial Dermatoses / Q000188:drug therapy*; D006801:Humans; D017495:Hyperpigmentation / Q000188:drug therapy*; D008297:Male; D008543:Melanins / Q000037:antagonists & inhibitors*; D008713:Methimazole / Q000008:administration & dosage / Q000627:therapeutic use*; D009784:Occupational Diseases / Q000150:complications; D009195:Peroxidase / Q000037:antagonists & inhibitors; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D003879:Dermatologic Agents; D008543:Melanins; D014284:Triiodothyronine; D008713:Methimazole; D013972:Thyrotropin; D009195:Peroxidase; D013974:Thyroxine