We have examined the effect of the iron chelating agent, desferrioxamine on different models of acute inflammation initiated by the irritants carrageenan or calcium pyrophosphate crystals. Depending on the dose of drug used and the time at which the lesion is examined both pro- and anti-inflammatory effects were observed as judged by measurement of leucocyte accumulation and oedema formation. The anti-inflammatory effects of desferrioxamine were supported by a decrease in concentration of the acute phase reactant alpha 1 glycoprotein. Our findings suggest that iron has a complicated relationship with the inflammatory process.