Black urine.
A patient is described in whom spontaneous blackening of the urine, due to melanin formation, resulted from treatment with alpha-methyldopa. The colour change became apparent only after the correction of a severe postoperative hyponatraemic alkalosis, the urinary pH had become alkaline, as melanin formation in acid urine is very slow.
D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007010:Hyponatremia / Q000188:drug therapy; D008543:Melanins / Q000652:urine*; D008750:Methyldopa / Q000009:adverse effects*; D008875:Middle Aged; D011183:Postoperative Complications; D014556:Urine / Q000032:analysis
D008543:Melanins; D008750:Methyldopa