What are drugs? What are the sources of drugs?

Drugs are chemical substances that, when consumed or administered, can alter the function of the body, either by enhancing or inhibiting biological processes. They can have therapeutic effects (such as treating or preventing diseases) or cause alterations in mood, perception, and consciousness. Drugs can be classified based on their effects, such as medicinal drugs (used for treatment), recreational drugs (used for pleasure), or illicit drugs (used unlawfully or without medical supervision).

Drugs work by interacting with the body’s cells, tissues, and organs to bring about their effects. For example, pain relievers (like aspirin) target pain receptors, while antibiotics (like penicillin) target bacteria to fight infections.

Sources of Drugs

Drugs can be obtained from various sources, primarily falling into the following categories:

1. Natural Sources:

   • Plants: Many drugs come from plants, which have been used for centuries in traditional medicine. For instance:
     • Morphine, a potent painkiller, is derived from the opium poppy.
     • Quinine, used to treat malaria, comes from the bark of the cinchona tree.
     • Cannabis (marijuana) is derived from the cannabis plant and is used for its medicinal properties.
   • Animals: Some drugs are derived from animals, such as:
     • Insulin, used to manage diabetes, was originally derived from the pancreas of cows or pigs.
     • Heparin, a blood thinner, comes from the intestines of pigs.
   • Microorganisms: Several important drugs are sourced from microorganisms (bacteria, fungi, etc.):
     • Penicillin, the first antibiotic, was discovered from the fungus Penicillium.
     • Streptomycin comes from a type of bacterium called Streptomyces.

2. Synthetic Sources:

   • Many modern drugs are synthetically produced in laboratories using chemical processes. These drugs are often designed to mimic or enhance the effects of natural substances. For example:
     • Aspirin is a synthetic compound originally derived from salicylic acid in willow bark.
     • Artificial insulin is synthesized using recombinant DNA technology, where bacteria are engineered to produce the hormone.
   • Synthetic drugs can also include those that are entirely man-made, such as synthetic opioids (e.g., fentanyl), which have no direct natural counterpart.

3. Biotechnological Sources:

   • Biotechnology has enabled the creation of biologic drugs, such as monoclonal antibodies, which are produced using living cells. For example:
     • Humira (adalimumab), used for autoimmune diseases, is a monoclonal antibody that targets specific immune system components.
     • Erythropoietin (EPO), a drug that stimulates red blood cell production, is produced using recombinant DNA technology in cells.

4. Minerals:

   • Some drugs are derived from minerals, often in the form of salts or compounds. For instance:
     • Lithium, used to treat bipolar disorder, is obtained from the mineral lithium carbonate.
     • Magnesium sulfate (Epsom salts) is used in medicine for its muscle-relaxing and anti-inflammatory properties.