We present a patient who developed a severe haemolytic anaemia as a result of ingestion of a naphthalene-containing anointing oil. Previous reports of naphthalene-induced haemolytic anaemia are reviewed. Predisposing factors to haemolysis are outlined and the variability in the haematological response to naphthalene is discussed. It is clear that ingestion of anointing oil is dangerous; even topically, significant absorption of naphthalene may occur especially in infants, as it is oil-based. Because of these dangers, the use of naphthalene-containing anointing oils should be strongly condemned.