Botanical name: 

The rhizome and roots of Iris versicolor, Linné (Nat. Ord. Iridaceae). Common in wet places in the United States. Dose, 5 to 20 grains.
Common Names: Blue Flag, Larger Blue Flag, Fleur de Luce.

Principal Constituents.—Volatile oil, a whitish-yellow resin, a trace of an alkaloid, and a comphoraceous body.
Preparation.—Specific Medicine Iris. Dose, 1 to 20 drops.

Specific Indications.—Enlarged, soft and yielding lymphatic enlargements; thyroid fullness; splenic fullness; chronic hepatic disorders, with sharp, cutting pain, aggravated by movement; clay-colored feces, with jaundice; nausea and vomiting of sour liquids, or regurgitation of food, especially after eating fats or rich pastry, or ice cream; watery, burning feces; rough, greasy skin, with disorders of the sebaceous follicles; abnormal dermal pigmentation.

Action.—Iris stimulates the glands of the body to increased activity and impresses the nervous system. In large doses it is emeto-cathartic, acting violently, the vomitus being acid and the catharsis watery and persistent and accompanied by colic and rectal heat. Iris increases the hepatic and pancreatic secretions, as well as those of the intestines. Iris also salivates, but without injury to the gums and teeth. Salivation from vegetable sialagogues may be differentiated from that caused by mercury by the absence of mercurial fetor and lack of sponginess of the gums or loosening of the teeth. Neuralgic pain is said to be produced by iris when given in large doses; and when even moderately full therapeutic doses are administered it produces a more or less persistent belly-ache and mild catharsis. Iris is capable of causing gastro-enteritis resulting in death. To be effective iris preparations must be made from prime, heavy, resinous root-stocks; when old and light, like tan-bark, iris produces neither physiologic nor therapeutic effects.

Therapy.—External. Specific Medicine Iris has been painted upon goitre with good results, though it is effectual in but few instances, and the type is not as yet well defined. It is also advised as an efficient local treatment for psoriasis, chronic itching eczema, various types of tinea, prurigo, and crusta lactea. In all of the preceding disorders the drug should be given internally while being applied externally.

Internal. Iris is alterative and cholagogue. It exemplifies as fully as any drug the meaning of the term alterative as used in Eclectic therapy. Perhaps this is best expressed to-day by saying that it corrects perverted metabolism. Iris, in small doses preferably, quietly stimulates the glandular structures of the body, both the glands with outlets and the ductless glands. It promotes waste and excretion, two processes necessary before repair can well take place. In broad terms it is a remedy for "bad blood" and imperfect nutrition. The term "bad blood" or blood dyscrasia has, as a rule, little relation to the blood itself, but pertains chiefly to imperfect lymphatic elimination and faulty retrograde metamorphosis. Iris impresses the thyroid function, is of great value in the adenopathies of syphilis and skin affections, with imperfect functioning of the lymphatic system resulting in enlarged lymph nodes. Hepatic torpor, splenic fullness, and jaundice, with clay-colored stools are influenced for good by it, the drug acting quietly as an alterative when given in small and repeated doses.

Iris should be used in the various cachexias—lymphatic, scrofulous and syphilitic. It proves more or less useful in some cases of goitre or enlarged thyroid, whether the enlargement be constant, or merely the temporary fullness associated with the menstrual function, normal or abnormal. When it does good it is chiefly in reducing enlargement, and appears to have but little influence upon the tachycardia and other disturbances of hyperthyroidism. As a rule, soft glandular enlargements are best treated with iris, and hard enlargements with phytolacca. However, iris is sometimes surprisingly effective in goitre, while more often it seems to fail completely. The exact type most benefited has never been clearly defined. In order to obtain satisfactory results at all, the use of the drug must be continued over a period of several months. In exophthalmic goitre it may be given early, but without great hope of doing more than to affect the bodily glandular functions, thereby improving the general health of the patient. The same may be said for it in Addison's disease, in which it has sometimes benefited, but has not, of course, cured. Iris is often useful in splenic fullness, and ovarian and uterine turgescence in cachectic individuals.

Minute doses of iris relieve gastric irritation, with nausea, vomiting, and gastralgia. In like doses it is sometimes useful in cholera infantum, and in either diarrhea or dysentery, both with large, slimy evacuations, repeated small doses have proved very effectual. Still for all these bowel troubles it is far inferior to ipecac. It is quite certain, however, to relieve sick headache dependent upon indigestion, and bilious headache, with nausea and sour and bitter vomiting, and clay-colored stools. In fact one of the most important uses for iris is in that complex condition included in the elastic denomination "biliousness". For regurgitation of fatty foods or pastries it is especially effective. In hepatic congestion, with constipation, and sharp-cutting pains, increased by motion, iris frequently gives relief. When constipation depends upon hepatic and intestinal torpor and in duodenal catarrh, with jaundice and clay-colored feces, iris should be considered as a possible remedy. Aching pain, with pressure beneath the scapulae, usually dependent upon hepatic wrong, is relieved by 1 to 5 drop doses of specific medicine iris.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.