New drugs to treat people are constantly being developed. This is necessary because new diseases are constantly emerging, and old ones are becoming resistant to currently used drugs because of selection pressure caused by the use of those drugs. There are also still many conditions for which there is no treatment available.
Methods of Developing New Drugs
Drugs may be accidentally discovered, for example when researching another field. It is well known that Alexander Fleming discoved Penicillin accidentally because of keeping an untidy laboratory while investigating the properties of Staphylococci.
Many people (80% of the World's population according to WHO) rely on traditional medicines and drugs. This is especially so in less economically developed countries, where there is less knowledge or less money to use use modern drugs.
Some modern drugs are derived from traditionally used ones. For example, Hippocrates used an extract from willow bark to relieve pain, and a similar extract has been used in Britain since the Middle Ages. The active ingredient was later isolated and is now used in Aspirin.
Drugs can be discovered and developed by observing wildlife. Many animals use drugs to protect them from diseases. For example, some birds line their nests with medicinal leaves to protect their young, and some furred animals use citrus oils as insecticides and antiseptics.
A lot of modern drugs have been developed by looking at plants, especially tropical plants because of their great diversity. chemical fingerprinting technology is being used to more effectively screen chemicals for their natural medicinal properties.
Much of recent research has concetrated on looking at Genetics. For example, biologists have been researching how Streptomyces, the main source of new drugs in the past 50 years, codes for the drugs it produces.
Biologists also look at how pathogenic microorganisms interact with human cells. By looking the Cell Receptor Sites used by a specific pathogen, for example by looking at the sequence of amino acids that produces it, drugs can be developed that block that Receptor Site.
Genetics may be of further help in comaring the Human Genome with that of a plant, for example. In doing so, new drug to help humans may be developed.