Introduction to Drugs
5 Minutes
Introduction to drugs and medicines for students, exploring how medicines increased human lifespan and how drugs are made. A science lesson in English.
- How medicines increased average human lifespan from 36 to 78 years
- Natural drug sources like plants and animals versus chemicals
- WHO guidelines for medicines and major types like anesthetics
What this lesson teaches
A drug is a chemical substance used to treat, cure, or prevent illness and relieve pain. In medical science, the word drug simply refers to medicine rather than harmful substances.
How medicines lengthened human lives
During the 1800s, only 35 percent of people lived without illness, while the remaining 65 percent fell sick and died early, leaving the average lifespan at just 36 years. By 2020, the average human lifespan reached 78 years because medicines and vaccines were developed to treat deadly conditions. Even though new diseases like Ebola, Nipah, and Corona continue to appear, researchers produce treatments rapidly to stop widespread deaths. In addition, the introduction of anesthetics after the 1800s prevented people from dying of unbearable pain during surgeries, allowing doctors to save many lives.
Sources of medicines
Medicines are prepared from biological organisms or synthesized artificially using chemicals:
- Plants provide natural chemicals, such as the drug quinine used to treat patients with malaria.
- Animals supply medicinal substances, such as insulin obtained from cows and pigs to manage diabetes.
- Microorganisms are also collected and used as natural sources to create certain drugs.
- Artificial chemicals are formulated in laboratories to produce common fever tablets like paracetamol and anacin.
World Health Organization guidelines
The World Health Organization, known as the WHO, has established essential requirements that every medicine must satisfy:
- The medicine must be non-toxic and completely free of harmful or poisonous substances.
- It must act effectively once it enters the body of an infected patient.
- It must not produce negative side effects or interfere with normal bodily functions.
Purposes and types of drugs
Drugs serve two major purposes: curing illnesses, and preventing diseases, relieving pain, or stopping infections. People study pharmaceutical chemistry to understand the nature of these substances, how they are manufactured, and how they should be safely stored. Seven major classes of drugs are widely used in healthcare: anesthetics for surgery, analgesics for pain relief, antipyretics for fever, antiseptics and antibiotics to fight infections, antimalarials to treat malaria, and antacids for stomach relief.