The case reported here appears to be an example of anaphylaxis-like sensitization of a patient to her own breast milk. In a previous communication, I 1 mentioned having observed three patients who had a serum sickness-like illness following rapid absorption of their own milk. The condition in each case could be relieved through the use of a breast pump. One case, which followed the weaning of a baby, was quite severe and necessitated the use of repeated doses of epinephrine. The following case of breast milk sensitiveness was more completely studied than those previously reported. The condition was transferred passively, and rapid desensitization followed treatment. REPORT OF CASE History. —A woman, aged 35, of strong allergic strain, following the weaning of her second child seven years previously, noticed that the breast continued to secrete a little milk. This usually amounted to about a drachm a day and was noticed constantly