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the condition is seen most commonly in women ( accounting almost 90% of the cases ) of child - bearing age with fitzpatrick skin types iv to vi , especially among those living in areas of intense uv radiation .
while all races are affected , there is a particular prominence among latinos , especially of caribbean origin , and among asians .
the cause of melasma is multifactorial and includes pregnancy , sun exposure , hormone therapy , use of cosmetics , and racial or genetic effects .
a majority of cases are related to sun exposure , pregnancy , or oral contraceptives .
based on the distribution of the facial lesions , melasma can be classified into three types , namely malar , centrofacial , and mandibular patterns . based on wood 's lamp examination , it can be classified as epidermal , dermal , mixed , and indeterminate variants .
conventional treatment of melasma includes elimination of any possible causative factors coupled with use of a sunscreen and hypopigmenting agents like hydroquinone , kojic acid , azelaic acid,[810 ] deoxyarbutin , ascorbic acid , singly , or in combination like the kligman 's formula.[1316 ] often these agents are used with other therapies like chemical peeling with glycolic acid or trichloacetic acid , dermabrasion , and laser therapy . despite these measures , treatment of this recalcitrant disorder is often difficult and unsatisfactory .
the present study was undertaken to compare the therapeutic efficacy of some currently available modalities and to assess their safety in the treatment of melasma .
one hundred and sixty patients of all age groups and both sexes clinically diagnosed as melasma who presented for the first time were selected for this study .
a detailed history was taken with reference to the onset , duration , progression , family history , obstetric history , drug history , previous treatment , and sun exposure .
dermatological examination of the lesions was carried out with respect to morphology , configuration , distribution and the melasma was categorized into epidermal , dermal or mixed based on wood 's lamp examination .
the patients were further classified according to the distribution of the lesions into malar , centrofacial , or mandibular .
all patients were informed regarding the nature of disease , course , prognosis , and the probable adverse effects of the treatment modalities . after an informed consent ,
patients were advised to apply the given regime only on the affected areas at night time ; starting with 2 h and gradually increasing the duration of application if no side effects ( erythema , burning , desquamation , dryness ) were experienced . strict sun protection along with use of broad spectrum sunscreens was advised .
five different regimes were used : regime i : kojic acid ( 3%)+vitamin c ( 2% ) cream regime ii : azelaic acid ( 20% ) cream regime iii : hydroquinone ( 2%)+tretinoin ( 0.025%)+ mometasone furoate ( 0.1% ) cream regime iv : arbutin ( 5%)+glabridin ( 0.5% ) cream regime v : arbutin ( 5%)+glycolic acid ( 10%)+kojic acid ( 3% ) cream each patient was followed up at monthly intervals and response to treatment was evaluated subjectively and objectively .
grading was done based on subjective assessment as follows : grade i : slight improvement , barely noticeable ( up to 25% ) grade ii : moderate improvement , noticeable ( 25 - 50% ) grade iii : obvious improvement ( 51 - 75% ) grade iv : marked improvement ( > 75% ) grading was done based on objective assessment by melasma area and severity index ( masi scoring ) .
the face is divided into 4 areas  forehead ( f ) , right malar region ( mr ) , left malar region ( ml ) and chin ( c ) corresponding to 30% , 30% , 30% and 10% of the face respectively .
the melasma in each of these four areas ( af , amr , aml , ac ) is given a numerical value .
severity of melasma is based on two factors , darkness ( d ) of melasma compared with normal skin and homogeneity ( h ) of hyper pigmentation .
the rating scale for darkness of melasma is as follows : 0  normal skin color without any hyper pigmentation 1  specks of involvement 2  small patchy areas of involvement < 1.5 cm in diameter 3  patches of involvement > 2 cm in diameter 4  uniform skin color without any clear areas the rating scale for homogeneity of melasma is as follows : 0  normal skin color without any hyper pigmentation 1  barely visible hyper pigmentation 2  mild hyper pigmentation 3  moderate hyper pigmentation 4  severe hyper pigmentation to calculate the masi score , the sum of the severity rating for darkness ( d ) , and homogeneity ( h ) is multiplied by the numerical value of the areas involved ( a ) and by the percentages of the four facial areas .
therefore , masi = 0.3 ( df + hf ) af + 0.3 ( dmr + hmr ) amr + 0.3 ( dml + hml ) aml + 0.3 ( dc + hc ) ac the maximum score of masi is 48 with minimum 0 .
the face is divided into 4 areas  forehead ( f ) , right malar region ( mr ) , left malar region ( ml ) and chin ( c ) corresponding to 30% , 30% , 30% and 10% of the face respectively .
the melasma in each of these four areas ( af , amr , aml , ac ) is given a numerical value .
severity of melasma is based on two factors , darkness ( d ) of melasma compared with normal skin and homogeneity ( h ) of hyper pigmentation .
the rating scale for darkness of melasma is as follows : 0  normal skin color without any hyper pigmentation 1  specks of involvement 2  small patchy areas of involvement < 1.5 cm in diameter 3  patches of involvement > 2 cm in diameter 4  uniform skin color without any clear areas the rating scale for homogeneity of melasma is as follows : 0  normal skin color without any hyper pigmentation 1  barely visible hyper pigmentation 2  mild hyper pigmentation 3  moderate hyper pigmentation 4  severe hyper pigmentation to calculate the masi score , the sum of the severity rating for darkness ( d ) , and homogeneity ( h ) is multiplied by the numerical value of the areas involved ( a ) and by the percentages of the four facial areas .
therefore , masi = 0.3 ( df + hf ) af + 0.3 ( dmr + hmr ) amr + 0.3 ( dml + hml ) aml + 0.3 ( dc + hc ) ac the maximum score of masi is 48 with minimum 0 .
of the 160 patients enrolled in the study , 127 were females and 33 were males , all above 18 years of age .
the majority , 132 patients ( > 80% ) , belonged to the age group of 21 - 40 years .
9% were below 20 years and 9% were above 40 years . in our study 105 ( 65% ) had malar distribution and 55 ( 35% ) had centrofacial type of melasma and there was no patient with mandibular distribution .
comparison of various treatment regimes - subjective evaluation response to treatment based on masi score - objective assessment
in our study , the incidence of melasma was found to be 2% of all the patients presenting to the dermatology clinic .
almost all the patients ( > 80% ) in our study were in the age group of 21 - 40 years .
females constituted almost 79% ( 127 ) , while males constituted 21% ( 33 ) .
the higher incidence of melasma in females may be attributable to a hormonal influence as in pregnancy , use of oral contraceptive pills , and the use of cosmetics . among our patients ,
100 ( 62% ) were housewives , 16 ( 10% ) were outdoor workers , 10 ( 6% ) were students , and 34 ( 10% ) were office workers .
the higher incidence among outdoor workers may be attributed to sun exposure , while among students it reflects outdoor activities and a greater awareness . even though sun exposure aggravates melasma ,
housewives who may not have much photo exposure constitute a majority of our patients which probably indicates the importance of a hormonal influence in the etiology of melasma . in our study , 105 patients ( 65% ) had malar distribution , 55 ( 35% ) had centrofacial type , and none had mandibular type .
various studies indicate that the site of melasma is different in different parts of the world and also in different ethnic groups . in the indian subcontinent and among the darker races ,
a majority of patients show a malar distribution which is also corroborated in our study .
family history of melasma in a first degree relative was reported by 56 ( 35% ) of our patients .
melasma is known to be aggravated by the ingestion of certain drugs , the most common ones being oral contraceptive pills and antiepileptics like carbamazepine and phenytoin . in our study , 14 ( 8.5% ) patients gave a history of taking oral contraceptives or phenytoin .
sixteen patients ( 10% ) used cosmetics like fairness creams and all purpose moisturizing / vanishing creams which were perfumed . in our study , a majority of the patients enrolled did not give a history of using cosmetics ; hence no direct relation between the use of cosmetics and the causation of melasma could be inferred .
out of 160 patients , of which 127 were women , 32% developed lesions during pregnancy , which is a significant number ; also the onset was more common in the first pregnancy which is in concurrence with some of the other studies .
wood 's lamp examination is helpful in classifying melasma into epidermal , dermal , mixed and indeterminate based on accentuation of lesions under wood 's lamp .
epidermal melasma is known to respond to local treatment while dermal and mixed are less or non - responsive . in our study , 45 patients ( 28.5% ) showed accentuation of lesions on wood 's lamp examination , while 77 patients ( 48% ) showed a noticeable response to treatment , subjectively as well as objectively .
hence , we may conclude that wood 's lamp examination is not completely reliable in predicting response to treatment especially in the dark skinned population .
our study compared the various modalities containing : 
 tyrosinase inhibitors like hydroquinone , kojic acid , azelaic acid , glabridin , and arbutin.inhibitors of melanin production like ascorbic acidnon - selective suppressor of melanogenesis like corticosteroids . 
 
tyrosinase inhibitors like hydroquinone , kojic acid , azelaic acid , glabridin , and arbutin .
inhibitors of melanin production like ascorbic acid non - selective suppressor of melanogenesis like corticosteroids .
as far as the subjective assessment was concerned , the grading of response was done according to the percentage improvement in the lesions .
almost 70% patients on regime iii ( modified kligman 's formula ) showed grade ii and grade iii improvement at the end of three months [ figures 1 and 2 ] followed by regime ii , i , iv , and v. regime iii showed statistically significant response compared to regime v [ figures 3 and 4 ] .
pretreatment photo regime iii follow up photo at 3 months regime iii pretreatment photo regime v follow up photo at 3 months regime v for the objective assessment , the difference in masi score on day 0 and at the end of 3 months of treatment for all the regimes was taken .
after analysis of variance ( anova ) table and calculating the p value , the difference in mean reduction masi score in the five regimes was statistically significant . here
too regime iii showed more standard deviation and difference in the masi scores at day 0 and at the end of 3 months .
hence , the findings of objective assessment matched those of subjective assessment i.e. , modified kligman 's formula was the most superior treatment modality .
adverse effects to the various regimes were seen only in 38 patients ( 23.75% ) ; which included erythema in a majority while a few had burning sensation and desquamation and a very few had dryness .
we concluded that melasma constituted a major pigmentory problem other than vitiligo presenting to the dermatologist .
this study stresses the importance of young age , female sex , sun exposure , hormonal factors , certain drugs particularly o.c .
pills in the etiopathogenesis of melasma . among the currently available topical modalities for the treatment of melasma , the best response was to the modified kligman 's formula followed by azelaic acid followed by kojic acid and vitamin c combination followed by arbutin , glabridin combination and
it was also observed that the side effects were more with the most effective regimen .
hence , the ideal approach may be to initiate the treatment with the more effective modalities and later on maintain with plain hydroquinone or kojic acid .
background : melasma is a common acquired facial hypermelanosis . conventional treatment of melasma includes a sunscreen and hypopigmenting agents . the treatment of this recalcitrant disorder is often difficult and unsatisfactory.aims:the objective is to carry out a detailed clinical study of melasma and to assess the therapeutic effect and side effects of certain currently available topical modalities for the treatment of melasma.materials and methods:160 patients of all age groups and both sexes were treated sequentially with five different combination regimes for 3 months . 
 assessment of the response was done subjectively as well as by melasma area and severity index ( masi).results : out of the five modalities studied , the modified kligman 's formula was the most effective . 
 however , it had comparatively higher incidence of side effects.conclusions:among the currently available topical modalities for the treatment of melasma , the most effective combination is the modified kligman 's formula 
 . however , in view of the side effects it causes , it must be used with caution and proper counseling .