though it is commonly known to colour skin and sweat , pigmentation of hair has not been reported till date . a 45-year - old man presented with multiple hypopigmented ill defined hypoanaesthetic macules and multiple thickened peripheral nerves . slit skin smear from all the three sites ( earlobe , lesion , and normal skin ) were negative for acid fast bacilli . he was started on who multibacillary multidrug therapy ( rifampicin 600 mg and clofazimine 300 mg monthly pulse , dapsone 100 mg and clofazimine 50 mg daily ) . during the course of treatment he developed erythema and tenderness over the skin lesions suggestive of type 1 lepra reaction . since he was a known diabetic and had no features of neuritis he was treated with non steroidal anti - inflammatory medications . he continued to be symptomatic and was started on high dose of daily clofazimine ( 300 mg ) to avoid systemic steroids . he responded well to this form of treatment and had to be continued on high dose of clofazimine for two months . he was also continued on mb mdt for a total of 12 months . while on treatment he developed generalised pigmentation of skin as expected ; by the sixth month of mdt the patient noticed darkening of previously grey hair [ figure 1 ] . this being an unusual occurrence , his hair was sent for chemical examination to the chief chemical examiner 's laboratory ( kerala state ) . no dye could be extracted from the hair which proved that the pigmentation was not of exogenous origin . the darkened hair persisted eight months after completing treatment and reverted to the original grey colour after this period [ figure 2 ] . leprosy is a chronic disease caused by mycobacterium leprae affecting the peripheral nervous system , skin , and certain other tissues . dapsone , rifampicin and clofazimine are the drugs recommended by who for the treatment of leprosy , of which clofazimine is known to pigment the skin . clofazimine is a red iminophenazine dye , first used by browne and hogerzeil in the treatment of leprosy.[13 ] it is absorbed orally and accumulates in tissues . it has a very long half life of 70 days or more and is slowly excreted in urine , sebum , and milk . in the treatment of multibacillary leprosy , clofazimine is given as 300 mg monthly and 50 mg daily for a total of 12 months along with rifampicin and dapsone . clofazimine 300 mg daily is given in cases of lepra reactions as it has antinflammatory action in addition to its anti - leprosy action . of the 39 cases of hansen 's disease diagnosed and treated in our institution from july 2007 to june 2012 , 24 cases were given multibacillary multidrug therapy . however , only one person developed darkening of hair , which reverted to grey eight months after stopping treatment substantiating our claim that this was due to clofazimine . the pigmentation of hair was probably due to the high dose of clofazimine which the patient had received .
a 45-year - old man was treated with who multibacillary multidrug therapy for borderline leprosy and high dose daily clofazimine for lepra reaction . along with the expected side effect of skin pigmentation 
 , the patient also noticed darkening of previously grey hair . 
 this colour persisted eight months after completing multibacillary multidrug therapy .