Potassium iodide inhibits neutrophil chemotaxis.

We studied the effect of potassium iodide on the chemotaxis of neutrophil in 15 healthy subjects with a modified Boyden chamber method. Orally administered potassium iodide (15 mg/kg/day for 3 days) significantly inhibited the neutrophil chemotaxis in peripheral blood. It is postulated that the therapeutic effect of potassium iodide on erythema nodosum, nodular vasculitis, and Sweet's syndrome might be mediated through the inhibition of neutrophil chemotaxis by this agent.