Profound muscle weakness and hypokalemia due to clay ingestion.

We have presented the case of a 43-year-old woman with severe myositis due to clay ingestion and hypokalemia. EMG studies revealed a pattern consistent with myositis, and muscle biopsy showed a nonspecific diffuse myositis. The clay was shown to act as a potassium binder. With potassium replacement and discontinuance of clay ingestion, the symptoms and signs abated and laboratory values returned to normal.