In the clinical evaluation of hypertensive states, the use of the piperoxan (benodaine®) hydrochloride test1 for detecting adrenal medullary tumors offered another aid in establishing the presence of such tumors. Green2 reported that of 51 patients who had proved adrenal tumors, only 14 had the classical paroxysmal type of hypertension. The remaining 37 had sustained hypertension. Thorn, Hindle, and Sandmeyer3 suggested that each patient with severe hypertension should be investigated for pheochromocytoma, since hypertension may be cured by removing such a tumor. The piperoxan test, with its characteristic lowering of a sustained hypertension, provides a safe blood pressure response in the presence of a tumor. However, our recent experience with two cases has raised some doubt concerning the specificity of this test for pheochromocytoma. The diagnostic test was performed according to the method described by Goldenberg, Snyder, and Aranow.1
In Case 1 there was a "positive"