Tartrazine InducedFixedDrugEruption

A 29 year old oncology resident presented to a dermatologist with the complaints of burning pain and hyperpigmentation of lips of acute onset. He was a non smoker without any significant history of known drug allergy or symptoms suggestive of intestinal polyposis or any endocrinological disorders. He was not exposed to any local irritants in the form of chewing tobacco, its related products and other chemicals. Detailed history revealed that he had suffered from 3 episodes of diarrhea one day back, took a tablet containing combination of the drugs norfloxacinandtinidazole with tartrazine as a coloring agent. He felt burning sensation in upper and lower lips seven hours after the drug intake which increased in severity at night. On examination, hyperpigmentation and desquamation was noted which involved median portion of upperlip and right lateral portion of lower lip, not involving mucocutaneous junction or skin adjacent to lips(fig.1).Finally based on history, clinical examination and known allergic properties of the coloring agents used for coating the drugs, a diagnosis of Fixed Drug Eruption induced by Tartrazine was made. He was treated by moisturizers and steroid (momentasone) ointment. Further patient developedpostinflammatory hyperpigmentation(fig.2) at the site of eruption which was treated by local application of hydroquinone and momentasone ointment.