This section is from the book "Botanic Drugs Their Materia Medica, Pharmacology and Therapeutics", by Thomas S. Blair. Also available from Amazon: Botanic Drugs, Their Materia Medica, Pharmacology and Therapeutics.
Wild Indigo, Podalyria tinctoria. Not official in any standard except Homeopathic and Eclectic, but listed in the N. F. IV. The Homeopathic "provings" are those of asthenic type, with offensive secretions. Baptitoxine, its most active proximate, is said to be similar to cytisine from Cytisus laburnum. It is an active poison, causing increased reflex activity and death from central paralytic asphyxia. It always induces vomiting. There has been no pharmacologic study of baptisia or baptitoxine, but cytisine has been elaborately investigated. Nicotine, lobeline, and cytisine constitute a group of similar pharmacology, which will be given under "Lobelia" (q. v.). Now if Flugge was correct in claiming that baptitoxine and cytisine are identical, baptisia must be included in the lobelia-tobacco group pharmacologically. It is not in the same group botanically; but the toxic action of baptisia resembles that of lobelia.
In large doses baptisia is a violent emeto-cathartic, and in smaller doses is laxative and stimulates the gastro-intestinal mucous membrane. It is said to stimulate the liver and to be antiseptic.
On the whole, baptisia must be regarded as an active agent, useful medicinally only in small doses.
Whatever antiseptic properties the drug may or may not possess, it is admittedly most effective in the form of a fresh decoction. In the early days, such a dressing for gangrenous conditions and putrid discharges was justified; but in these days of effective antiseptic dressings of demonstrated activity, there is no occasion to employ baptisia.
As an internal remedy many claims have been made for baptisia, but they all unite in commending it for septic and typhoid conditions, such as typhoid fever, fetid evacuations, ulcerative conditions, and depraved secretions. More conservative clinicians of the Homeopathic and Eclectic Schools no longer employ it in typhoid fever, limiting its use to "typhoid conditions." Also the opinion is growing that the drug is of value only when used very early. Dosage averages about one drop of the fl. or 2 or 3 drops "Mother tincture."
My own employment of the drug causes me to respect the views of gentlemen who commend it, as it has acted well in 2- to 5-drop doses fl. in some minor cases in which I have employed it, chiefly dysenteric cases. I believe it possesses real utility in stimulating normal activity of the intestinal glandular structures; but I am not prepared to believe it possesses any specific effect upon septic processes. Certainly what little is known of its pharmacology would not lead one to expect any such actions from the drug; but the emeto-cathartic agents as well as drugs of the ipecac type, do seem to have a direct effect upon the intestinal mucosa that is more than mere stimulation, although even emetine is not a bactericide.
The lobelia type of drug, as baptisia seems to be, has an action on the ganglion cells which stimulate the involuntary muscles and gland cells; and this type also promotes suprarenal secretion. Theoretically, therefore, one would expect from analogy activity from baptisia if the preliminary considerations I have presented are based upon reliable data. This data, however, is admittedly more or less imperfect. It would seem that a drug admittedly so active, and which has been employed for so long, would have been ere this adequately investigated; but it has not been reported upon in any definite and critical way.