Manaca. Vegetable Mercury. Brumfelsia hopeana.

Botanical name: 

Manaca. Vegetable Mercury.—This is a portion of the root and stem of Brunfelsia Hopeana Benth. (Franciscea uniflora Pohl.), a Brazilian plant belonging to the Fam. Solanaceae. It occurs in pieces from a few inches to one foot in length, and about one-half inch in diameter, very tough and woody, with a yellowish center and a dark, very thin outer bark. The stem portion has a very small yellowish pith. H. B. Parsons (Am. Chem. J., vol. i, No. 6) came to the conclusion that it contains no alkaloid, but E. Lenardson (In. Dis., Dorpat, 1884) asserts that he has found in it an alkaloid, manacine, besides a peculiar fluorescent substance supposed to be identical with gelseminic acid. Some investigators report failure to find any alkaloidal principles. E. P. Bruer (T. Q., 1882), as the result of experiments made upon the lower animals arrived at the conclusion that manaca acts upon the spinal cord, first stimulating, and then abolishing, the activity of the motor centers, the action being shared in by the respiratory centers. All the glands, especially the kidneys, were stimulated by it. In large doses he found it to produce in man lassitude, perspiration, and loose, greenish alvine discharges. Manaca has been very strongly recommended in the treatment of chronic or subacute rheumatism and syphilis. The dose of the fluidextract is from ten to thirty minims (0.6-1.8 mils) three times a day.


The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.