Ninety-eight patients with amebiasis were treated with the antibiotic, erythromycin (Ilotycin, Lilly). The results obtained in chronic amebiasis were highly satisfactory using a high initial dose (800 mg.), followed with a dose of 300 mg. every 6 hours, for 5 days, or a total of 6.5 gm. In all cases the stools containing E. histolytica cysts became negative. There was only one parasitological relapse in 36 patients thus treated. With smaller doses, the number of parasitological relapses was greater.
In acute amebiasis the results were spectacular. The acute symptoms of the disease disappeared promptly and the stools became negative in many cases by the third day, with clinical and parasitological cure in all of them at the end of the treatment. There was only one recurrence of symptoms and parasites among 28 patients treated with the above schedule. With smaller doses one observed the appearance of E. histolytica cysts in the stools after treatment in three out of eight patients with acute amebiasis.