Botany: The Science of Plant Life

by Norman Taylor

5. Drugs

Nearly all the drugs and medicines of importance are of vegetable origin, and from the days of Theophrastus the study of plants as possible medicines has been one of the chief phases of botanical research. In the early days all that was known about plants was learned by men interested in medicine, and some of their quaint old books are interesting relics of a bygone day. At present, pharmacognosy, or the science of medicinal plant products, is a highly developed specialty taught in medical and pharmacy schools. And yet the greatest medical college in this country has recently issued instructions to its staff of doctors and nurses to pay particular attention to “old wives’ remedies,” most of which consist of decoctions of leaves and other parts of plants. They have done this because all the knowledge of the scientists regarding medicinal plants has its origin in the habit of simple people turning to their local plants for a cure. The accumulation of the ages, aided and guided by the scientist, has resulted in the wonderful things that can now be done to the human body through the different drugs, nine-tenths of which are of plant origin.

There is almost no part of a plant that, in some species at least, has not been found to contain the various acids, alkaloids, oils, essences, and so forth, which make up the chief medicinal or, as the pharmacists call it, the active principle of plants. In certain of them the most violent poisons are produced, such as the poison hemlock which killed Socrates, and the deadly nightshade. And again the unripe pod of one plant produces a milky juice so dangerous that traffic in it is forbidden in all civilized countries, and yet later the seeds from that matured pod are sold by the thousands of pounds to be harmlessly sprinkled on cakes and buns by the confectioners. Earlier in this book it was said that plants are chemical laboratories, and nowhere has this alchemy been carried to such a pitch of perfection as in the hundreds of drugs produced by different plants. Reference to special books on that subject should be made by those interested, as only a few of our most important drug plants can be mentioned here.

QUININE

The Spanish viceroy of Peru, whose wife, the Countess del Chinchón, was dangerously ill of a fever in that country about 1638, succeeded through the aid of some Jesuit priests in curing the malady, with a medicine which these priests had gotten from the natives. It was a decoction from the bark of a tree, and its fame soon spread throughout the world as Peruvian bark. Even in those days malaria was the curse of the white man in tropical regions, and since then it is hardly too much to say that the discovery of this drug has made possible for white colonists the retention of thousands of square miles of tropical country that without it would in all probability be unfit for occupancy. To the natives, too, quinine has been one of the greatest blessings, and in some of the remote regions of the tropics the writer has found quinine more useful than dollars in getting help from fever-ridden natives, too poor and too remote from civilization to get the drug.

For more than a hundred and fifty years after the discovery of Peruvian bark it was always taken as a liquid, usually mixed with port, and an extremely noxious and bitter drink it made. The fine white powder which we now use in tasteless pellets or pills has made the drug even more useful than before.

The trees from which the bark is used all belong to the genus Cinchona, named for the first distinguished patient to benefit by it, and belong to the Rubiaceæ or madder family. There are at least four or five different species. For many years Peru and near-by states were the only source of the bark, and the English became convinced that the great trade in the drug would exterminate the tree, so in 1880 they introduced the plant into India. These cinchona plantations now provide most of the world’s demand, and some idea of what that means may be gleaned from the fact that in Ceylon alone over fifteen million pounds of the drug are produced annually. In India itself the plantations are largely government owned and quinine is sold in the post offices at a very low rate. In cinchona plantations strips of the bark are removed, and after a proper period of healing, the process is repeated. It takes about eight years before it is safe to begin cutting the bark.

ACONITE

Most doctors use aconite for various purposes and it is mentioned here chiefly as illustrating a common characteristic of many medicinal plants. The whole plant is deadly poisonous, and in the root there appears to be a concentration of this poisonous substance, which makes the plant one of the most dangerous known. All of the drug aconite is derived from Aconitum Napellus, a monkshood, belonging to the buttercup family. It is a perennial herb with beautiful spikes of purple-blue flowers, not unlike a larkspur, and is a native of temperate regions of the Old World. A related Indian species has been used for probably thousands of years by the natives. They poison their arrows with it and so deadly is the drug that a tiger pricked by such an arrow will die within a few minutes. It is conceded to be the most powerful poison in India. Numerous accidents have resulted in Europe from careless collectors of the roots of horseradish, who sometimes get aconite roots mixed with that condiment, usually with fatal results.

So many other plants are violently poisonous, and yet yield the most valuable drugs, that the greatest care has to be used in their collection and preparation. The habit of many children of eating wayside berries should be discouraged, as some of our most innocent-looking roadside plants are actually deadly if their fruits or foliage are eaten. Fortunately only a very few plants are poisonous to the touch, notably poison ivy and poison sumac, and some of their relatives.

OPIUM AND MORPHINE

Almost no plant product has caused more misery and relieved more pain than the juice of the unripe pod of the common garden poppy, Papaver somniferum. From it opium is extracted, the chief constituent of which is morphine. If tea can be said to have precipitated our war of independence, opium was indirectly the cause of the opening of China to the western world. The degrading effects of opium had become so notorious that the Chinese in 1839 destroyed large stocks of it, mostly the property of British merchants, and prohibited further importations. In the subsequent negotiations which ended in war, China was opened up to trade. No civilized country now openly permits the sale of opium, although there is still a good deal of it used in practically all parts of the world. The effects of lassitude, subsequent ecstasy, and stupefaction are due to an alkaloid, the continued use of which forms a drug habit of serious consequences. Parts of China, Turkey, Persia, and Siam are said to be still large users of opium which is chewed, or more often smoked. Until comparatively recently fifteen out of every twenty men in some of these countries were regular users of the drug. The legitimate use of morphine by physicians has done more than almost anything else, with the possible exception of cocaine, to relieve suffering, and there is consequently a considerable trade in the drug.

The home of this poppy is unknown, as it has been cultivated from the earliest days. The ancient Greeks and Romans knew it and the Egyptians grew it for opium. It is still grown in India and China, where, notwithstanding vigorous governmental measures, there is a large opium consumption. After maturity the pods of the poppy, from whose milky juice in its earlier stages the drug is obtained, produce many seeds. From these an oil is pressed which is widely used as a cooking oil in the East, and is perfectly harmless. The seeds are also used as bird seed and by confectioners.

COCAINE

In the northern part of South America the Peruvians and some of their neighbors were discovered by early explorers to be chewing the leaves of a native shrub, apparently with much profit and no evil after effects. It served them much as the betel nut does to the natives of India and other regions of the tropical East. With scanty or no food this apparently harmless intoxicant will carry both men and women over periods of severe fatigue. The shrub bearing these leaves is not over four or five feet tall and has bright green foliage and small white flowers.

Quite different in its effects has been the drug which has been extracted from this plant, known as Erythroxylon Coca. Far from being a beneficial and harmless stimulant, cocaine is now one of the drug evils of our time. Its use, outside that prescribed by physicians, is forbidden practically everywhere, but its consumption in this country, aside from its great and legitimate use as a relief from pain, is still very large.

The number of drug plants is legion, so large in fact, that volumes have been filled with descriptions and notes about them. A few of the most important, omitting those already mentioned, are listed below:

Drug	Derived from the	Native
Betel nut.	Seed of Areca Catechu.	India.
Calamus.	Rootstock of Acorus Calamus.	Eastern U. S. and in Asia.
Sarsaparilla.	Roots of various species of Smilax.	Tropical America.
Saffron.	Stigmas of Crocus sativus.	Europe.
Arrowroot.	Rootstock of Maranta arundinacea.	Tropical America.
Cubeb.	Unripe fruit of Piper Cubeba.	Old World tropics.
Creosote.	Wood of Fagus americana and F. sylvatica.	North America and Europe.
Hydrastis.	Rootstock of Hydrastis canadensis.	Eastern N. America.
Star Anise.	Fruit of Illicium anisatum.	Southern China.
Camphor.	All parts of Cinnamomum Camphora.	China and Japan.
Witch-hazel.	Leaves and bark of Hamamelis virginiana.	Eastern N. America.
Licorice.	Underground parts of Glycyrrhiza glabra.	Europe.
Cascara Sagrada.	Bark of Rhamnus Purshianus.	Western United States.
Ginseng.	Rootstock of Panax quinquefolium.	Eastern N. America and Asia.
Wintergreen.	Leaves of Gaultheria procumbens.	Eastern N. America.
Nux vomica.	Seeds of Strychnos Nux vomica.	India.
Digitalis.	Leaves of Digitalis purpurea.	Europe.
Ipecac.	Root of Uragoga Ipecacuanha.	Brazil.
Castor oil.	Seeds of Ricinus communis.	Africa or India.