This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
As in chemistry, so also in botany, plants sustain definite relationships to each other; and as from its chemic affiliation we get an idea of the therapy of any new substance, so from its botanic classification we obtain some insight into its therapeutic indications. While the different species of a genus may vary to quite an extent in their range of action, yet their general action is usually along some definite line, and if the genus in general is inert therapeutically, we need seldom expect much from any newly introduced species of that genus.
The Ranunculaceae usually possess an acrid and poisonous juice, the active constituent of which is more or less volatile. Plants of this natural order should be worked fresh or in a comparatively recent state in making tinctures or extracts and heat should not be employed in the process. The roots of some species contain more or less permanent alkaloids, and these roots need not be handled so carefully. Pulsatilla is an instance of the first class and aconite root of the second class. Nearly all plants of this order are more or less poisonous, and externally applied are vesicants. Clematis or virgin's bower is an exception, but it is actively purgative. Hepatica also is not an active drug, while Xanthoriza is esteemed as a bitter tonic.
The Magnoliaceae are characterized by aromatic tonic properties.
The Berberidaceae possess acrid and bitter properties. Berberis, caulophyllum, podophyllum, and jeffersonia are instances of this order. They are active because of resins and alkaloids, and are readily manipulated pharmaceutically.
The Cruciferae are non-poisonous, acrid irritants with volatile constituents. Mustard, horse-radish, and shepherd's purse are of this order.
The Malvaceae, a tropical order, gossypium being the only species much employed in medicine, are worthy of investigation. They deteriorate very much by drying.
The Anacardiaceae possess a resinous or milky and commonly poisonous juice. There are over a hundred species, mostly of tropical habitat, and not investigated medicinally. The genera represented by the various species of Rhus have been well studied.
The Rhamnaceae is another interesting order. "Cascara sagrada," which is properly Rhamnus purshiana, was made light of some years ago, but it has proven so valuable as to suggest that the same manipulation of the bark that develops its properties may be applicable with other shrubs and trees. There are over forty genera of this order.
The Leguminosae include melilotus, baptisia, American senna, and other remedies of some importance. The three sub-orders embrace many tropical plants little studied as yet, but some of them contain coumarin, a substance occurring in several of the adulterants of smoking tobacco and markedly influencing the heart.
The Rosaceae, a large and important order embracing many of our domestic fruits. Wild-cherry, agrimony, and others are used in medicine.
The Umbelliferae embrace many poisonous species which grow in wet places. Some of those thriving in dry sections possess useful aromatic properties. Conium, eryngium, and the familiar wild carrot and cow parsnip are of this order.
The Ericaceae are diuretics, as instanced by uva-ursi and arbutus.
The Labiatae are non-poisonous aromatics, and include the mints.
The Solanaceae are narcotics. The night-shades, hyoscyamus, and stramonium are of this order. Only assayed preparations of these drugs are to be relied upon, and great care is necessary in their manipulation. The recent herbs make up well into standard tinctures, and such preparations are preferable to non-assayed fluid-extracts.
The Euphorbiaceae are acrid and emetic. The varieties of spurge and stillingia are native to the United States. Some of them are alterative.
These botanical data are largely derived from a "Manual of the Medical Botany of North America," by Prof. Laurence Johnson. For more detailed information the reader is referred to it and to the various Dispensatories.
A superb medical botany, illustrating in colors one hundred and eighty American medicinal plants, has been prepared by Dr. C. F. Millspaugh. These books will cover both the regular and sectarian lists of plant remedies.