The dried peeled fruit, freed from seeds, of Citrullus Colocynthis. Imported chiefly from

Fig. 193   Colocynth (peeled), half the natural size

Fig. 193 - Colocynth (peeled), half the natural size

Smyrna, Trieste, France, and Spain.

Characters. - Light, spongy, white or yellowish-white balls, intensely bitter in taste. The pulp from which the seeds have been removed only is officinal.

Composition. - The active principle is a glucoside, colocynthin, which is soluble in water and alcohol, not in ether. The remaining part of the pulp consists principally of resinous matter.

Dose. - Of the pulp, 2-8 gr.

Preparations

B.P.

Dose.

Extractum Colocynthidis Compositum .........................................

3-10 gr.

Pilula Colocynthidis Composita (vide p. 522) ...............................

5-10 gr.

„ „ et Hyoscyami (vide p. 522)....

....5 10 gr.

U.S.P.

Extractum Colocynthidis .............................................................

..... Seldom used alone.

" " Compositum ......................................

..... 5-20 gr.

Pilulae Catharticae Compositae (vide p. 523) ............................

..... 1-3 pills.

Extractum Colocynthidis Compositum. Compound Extract of Colo-oynth, B.P. - Colocynth pulp, 6 oz.; extract of Socotrine aloes, 12 oz.; resin of scammony, 4 oz.; curd soap, in powder, 3 oz.; cardamom seeds, in finest powder, 1 oz.; proof spirit, 1 gallon. An extract of the colocynth is first made, and then mixed with the other ingredients.

In the U.S.P. a simple extract is already officinal, and the proportions are - extract of colocynth, 16 parts; aloes, 50; cardamom, 6; resin of scammony, 14; soap, 14; alcohol, 10.

Physiological Action. - The active principle colocynthin acts as a powerful cathartic on the intestines whether swallowed, administered hypodermically, or injected into the circulation. In small doses it increases peristalsis, and the secretions from the intestines and liver. It thus produces watery and mucous motions, frequently accompanied by griping. In large doses it causes gastro-enteritis with mucous and bloody stools. It appears to act also on the urinary system, as Tidy found inflammation of the kidneys and bladder, as well as of the rectum, in dogs poisoned by it; it is said to act as a diuretic.

Uses. - It is used in obstinate chronic constipation, especially if there is a tendency to congestion of the brain, as in plethoric people. It is also used in amenorrhoea. It is apt to gripe if given alone; hence it is well to combine it with other purgatives and with sedatives such as hyoscyamus. It may sometimes be advantageously combined with mercurial pill.