ABSTRACT
Acquired Methemoglobinemia is unusual. It should be suspected in a child presenting with acute or subacute onset of cyanosis when respiratory and cardiovascular reasons are unlikely. Here, the venepuncture reveals dark brown [chocolate] colored blood. In spite of free flow supplement of 100% oxygen, the pulse oximetry shows low oxygen saturation while blood gas analysis shows normal or elevated PaO[2].The measurement of methemoglobin level is diagnostic and history of exposure to the offending agent is contributory. Intravenous Methylene blue is highly effective to tide over the dangerous consequences. Overdose or accidental ingestion of dapsone tablets has been reported to cause symptomatic acquired methemoglobinemia in children and adults. This appears to be the first case reported in a young child from the Middle East Gulf region