postfinasteride syndrome ( pfs ) is a symptom complex which occurs in patients taking finasteride . the united states food and drug administration approved the use of finasteride for benign prostatic hypertrophy ( bph ) as well as androgenic alopecia ( aga ) while dutasteride is approved only for bph . we describe a case of pfs with an atypical presentation in a patient treated with finasteride for aga . the present case illustrates the atypical as well as so far irreversible nature of pfs in the patient as well as challenges in its management . in january 2010 , a 33-year - old adult male presented with a history of hair loss . he was diagnosed to be a case of aga and was prescribed dutasteride 0.5 mg once a day for a month . during the course of treatment , he complained of generalized itching , burning micturition , abdominal discomfort , and seborrhea . the total serum testosterone level was 495.14 ng / dl in september 2012 . in october 2014 he was prescribed finasteride 1 mg ( instead of dutasteride 0.5 mg ) once a day . similar adverse effects such as itching , burning micturition , abdominal discomfort , skin rash , and seborrhea were observed again [ figure 1 ] . keratotic follicular papules on shoulders and back along with few pustules since there was no resolution of symptoms , a series of tests were ordered . of which hemogram ( hb 12.8 g / dl , packed cell volume 42.10% , red blood cell count 6.79 mill / mm , mean corpuscular volume 62 fl , mean corpuscular hemoglobin 18.8 pg , mean corpuscular hemoglobin concentration 30.30 , red cell distribution width 15.7% , total lymphocyte count 6800/mm , and platelet count 261,000 ) , renal function tests ( serum urea 21.60 mg / dl ; serum creatinine 1.00 mg / dl ) and urine examination were found to be normal . however , the total serum testosterone level had dropped down to 227.06 ng / dl in february 2016 . moreover , semen analysis was found to have pus cells while semen culture showed the moderate growth of enterococcus faecalis . the first center prescribed desloratadine 5 mg twice a day , combination of clindamycin 1% and benzoyl peroxide 5% , and povidone iodine ( antidandruff ) shampoo with restricted use of hair oil . the third center prescribed oxiconazole cream , loratadine , combination of benzoyl peroxide 2.5% and clindamycin 1% , alprazolam 0.5 mg , and dexchlorpheniramine along with antiseborrheic soap . clinical adverse experiences that are reported as possibly , probably , or definitely drug - related in 1% of patients treated with finasteride are decreased libido , erectile dysfunction , ejaculation disorder ( decreased volume of ejaculate ) , etc . postmarketing surveillance has reported finasteride to be associated with breast tenderness and enlargement and even male breast cancer ; depression ; hypersensitivity reactions including rash , pruritus , urticaria , and swelling of the lips ; and testicular pain . , in the present case , there were some symptoms that did not fit into the aforementioned list . these symptoms include burning micturition , seborrhea , as well as abdominal discomfort . moreover , these symptoms were so far irreversible . certain  causal relationship between finasteride and the atypical symptom complex according to the who - umc causality assessment system adverse drug reaction probability scale showed a  probable relation  between finasteride and the atypical symptom complex . both of these inferences were carried out assuming that rechallenge test was positive as finasteride and dutasteride belong to the 5- alpha - reductase group . the severity of the reaction as determined according to hartwig et al . revealed the adverse drug reaction to be severe ( level 6 ) as so far the adverse reaction seems to have caused permanent harm to the patient .
finasteride and dutasteride are commonly used 5-alpha reductase inhibitors . 
 while finasteride is a selective inhibitor of 5-alpha reductase type ii , dutasteride inhibits 5- alpha reductase type i and ii . 
 the united states food and drug administration approved the use of finasteride for benign prostatic hypertrophy ( bph ) as well as androgenic alopecia ( aga ) while dutasteride is approved only for bph . off - label use of dutasteride 
 is not uncommon in aga as well . 
 although the postfinasteride syndrome ( pfs ) is a well - established entity , its symptomatology is quite variable . here 
 , we describe a case of an atypical pfs in a patient treated with dutasteride and finasteride for aga . 
 the multisystem involvement and irreversible nature of this case warrant its reporting .