To the Editor:—
Under the caption "Pains in Lower Extremities" (195: 149, 1965) a letter describes recurrent episodes of severe pain in the lower extremities. The writer discusses the possibility of residual tabes, polycythemia, and gout.A common cause of rest pain has not been mentioned, namely, "night cramps." If the symptoms are due to this cause, they are relieved miraculously by the administration of quinine sulfate. This simple medication constitutes a very satisfactory therapeutic test.