|Medicinal Plants: An Expanding Role in Development (World Bank, 1996, 32 pages)|
Different levels of medicinal-plant usage are found in different industrialized countries, but all the levels are surprisingly high. For example, the German herbal-product market in 1989 was estimated at US$1.7 billion. And of the 500 million prescriptions written each year in the United States one in four is reported to involve a pharmaceutical derived from a leafy plant, an amount estimated in 1990 to be worth US$11 billion a year. Furthermore, almost all countries have a second outlet for plant-derived pharmaceuticals: non-prescription drugs. Many laxatives, cough and cold preparations, and over-the-counter sleep remedies come from plants.
The natural products in these prescriptions and over-the-counter preparations include:
1 quinidine, suppresser of out-of-sequence heartbeats from the
bark of Cinchona sp.;
2 quinine, antimalarial from Cinchona sp.;
3 pilocarpine, glaucoma treatment from Brazilian Pilocarpus sp.;
4 picrotoxin, used worldwide as a nervous system stimulant from Anamirta sp.;
5 L-Dopa, treating Parkinson's disease form Mucuna sp.;
6 bromelain, anti-inflammatory from pineapple Ananas sp.;
7 scopolamine, sedative from Datura sp.;
8 digitalin and digoxin, heart drugs from foxglove Digitalis sp.;
9 atropine, powerful pupil-dilator from belladonna Atropa sp.;
10 curare, muscle relaxant (notably used in surgery) from Chondrodendron sp.;
11 ephedrine, decongestant from Chinese Ephedra sp.;
12 ipecac, emetic and dysentery cure from Central American Cephaelis spp.; and
13 sennosides, laxative from Senna spp.
Some of these therapeutic compounds are now easier or cheaper to synthesize in industrial facilities. However, in the above list, numbers 1-7 are extracted from plant sources while those listed in numbers 8-13 can be produced synthetically but in developing countries at least still come mainly from the plant sources (Famsworth and Soejarto, 1991).
When the overall benefits to society are taken into account, the value of plant-derived pharmaceuticals is even more surprising. Principe (1991) estimates the total economic value to the United States to be at the very least $68 billion annually. In other words, when the improvements in people's health and capacities are factored in, the country reaps a financial dividend about six times the already large market value of the plant products themselves.