Acute severe methemoglobinaemia is an uncommon but life-threatening condition caused by a variety of oxidizing agents commonly used in both health care and industrial settings. Thus, recognition is important as it is readily treatable. The oxygen transport is compromised as a result of abnormal levels of oxidized haemoglobin, and this leads to skin discolouration and a variety of symptoms. Diagnostic confusion occurs as the oxygen saturations (SpO2) on the pulse oximeter are unreliable (Sharma V, Haber A. Acquired methaemoglobinaemia: a case report of benzocaine-induced methaemoglobinaemia and a review of the literature. Clin Pul Med. 2002;9(1):53-8). A case of severe methaemoglobinaemia due to self poisoning with barbicide is presented with a brief discussion of the patho-physiology and an overview of the treatment. A barbicidal overdose has never been reported before.
Keywords: Barbicide; Benzalkonium chloride; Isopropyl alcohol; Methemoglobinaemia; Methylene blue.