Different sources of drugs

Drugs are obtained from six major sources:

1. Plant sources

2. Animal sources

3. Mineral sources

4. Microbiological sources

5. Synthetic / Semisynthetic sources

6. Recombinant DNA technology

Plant Sources

Plant source is the oldest source of drugs. Most of the drugs in ancient times were derived from plants. Almost all parts of the plants are used such as leaves, bark, stem, fruits and roots.

Leaves: The leaves of Digitalis Purpurea are the source of Digitoxin and Digoxin, which are cardiac glycosides. Leaves of Eucalyptus give oil of Eucalyptus, which is important component of cough syrup. Tobacco leaves give nicotine.

Flowers: Rose gives rose water which is used as tonic.

Fruits: Senna pod gives anthracine, which is a purgative (used in constipation)

Roots: Rauwolfia serpentina gives reserpine, a hypotensive agent. Reserpine was used for hypertension treatment.

Bark: Cinchona bark gives quinine and quinidine, which are antimalarial drugs, Quinidine also has antiarrythmic properties.

Animal Sources

Many important drugs are derived from animal source. In most cases, these medicinal substances are derived from the animal’s body secretions, fluid or glands. Insulin, heparin, adrenaline, thyroxin, cod liver oil, beeswax and enzymes are some examples of drugs obtained from animal sources. Like plant products, drugs from animal sources may be crude (unrefined) or refined material.

Mineral Sources

Minerals (both metallic and non-metallic minerals) have been used as drugs since ancient times. Our body requires trace elements of minerals in order to maintain homeostasis. Patients lacking an adequate level of these materials may take specific mineral-based drugs to raise the level of minerals. Example of some mineral used in treatment of disease is: Iron is used in treatment of iron deficiency anemia, mercurial salts are used in Syphilis, gold salts are used in the treatment of rheumatoid arthritis.

Microbial Sources

Several life-saving drugs have been historically derived from microorganisms. Examples include Penicillium Notatum is a fungus which gives penicillin, Actinobacteria give Streptomycin, Aminoglycosides such as gentamicin and tobramycin are obtained from streptomycis and micromonosporas.

Synthetic/Semi synthetic Sources

A synthetic drug is a medication that is created in a laboratory through chemical synthesis. These drugs are not found naturally in the environment and are manufactured using various chemical compounds. Examples of synthetic drugs include certain antidepressants, painkillers.

A semi-synthetic drug is a medication that is created by modifying a naturally-occurring compound. These drugs are created by chemically modifying a naturally-occurring compound to create a new medication. Examples of semi-synthetic drugs include certain opioids, such as oxycodone and hydrocodone, which are derived from the opium poppy. Erythromycin antibiotic is derived from a type of bacteria called Streptomyces Erythraeus. It is used to treat various types of infections, such as respiratory tract infections and skin infections.

Recombinant DNA technology: Recombinant DNA technology is a method of creating new drugs using genetic engineering techniques. It is the most modern, advanced and new drug source. This technology allows scientists to manipulate the DNA of living organisms, such as bacteria or yeast, to produce specific proteins or enzymes. Examples of drugs produced using recombinant DNA technology include insulin which is used to treat diabetes, Interferon which is used to treat viral infections and certain types of cancer.