BMS 113 · Common Core (Tronc commun)Section 1.3 · Introduction to pharmacology
Section 3 of 31
How pharmacology became a science
Trace how medicines were discovered, and name the people and changes that turned pharmacology into an experimental science.
New to this course? How each section works
Learn gives you one short idea at a time. Each idea starts with a single sentence, then explains it, gives an example, and asks you a small question you can answer straight away.
Explore shows a diagram of the same ideas. Click the numbered parts to read what each one is.
Check asks a few questions. Answer them all correctly to finish the section and unlock the next one.
“Go deeper” is optional. It adds mechanism and extra detail for when you are ready — nothing you need for the checks is hidden there.
Why this matters
History explains why modern practice looks the way it does, from doses written in milligrams to the trials required before a drug is sold. Without it, regulation and testing can seem like pointless paperwork. You will meet these ideas again when the clinical trial phases are taught later in the course.
What you need to know first
You only need the idea from Unit 1.2 that a drug is a chemical substance that changes the body, and the everyday knowledge that people have long used plants as remedies. Unit 1.2 defines most of the vocabulary used here.
Words to know (5)
Experimental science
A way of working in which claims are tested by controlled observation instead of being accepted on authority. Giving curare to an animal and stimulating its nerve is an experiment.
Alkaloid
A nitrogen-containing substance made by a plant, often with strong effects on the body. Morphine, isolated from opium in 1805, was the first alkaloid.
Synthetic drug
A drug made by chemical manufacture rather than taken directly from a plant or an animal. Most modern drugs are semi-synthetic or fully synthetic.
Receptor
A protein structure on or inside a cell that receives a signal and starts a response. A drug designed to fit one receptor acts only where that receptor is found.
Antibiotic
A medicine that kills bacteria or stops them from growing. Penicillin, discovered by accident in 1928, was the first antibiotic.
One idea at a timeIdea 1 / 4
In one sentence For most of history, useful remedies were found by observation and trial, but they were explained by spirits, astrology or religion.
Early medicine mixed observation with belief
Disease has always been one of humanity’s greatest challenges, so the search for cures is as old as humankind. Early people believed disease came from evil spirits and treated it superstitiously; in some societies the effects of medicines were linked to the moon, constellations and planets, and astrology became part of medicine. Healing later became the privilege of clergymen, who attributed the power of medicines to divine strength. Gradually, by observing and mimicking sick animals, by accident, by experience and by trial and error, people separated helpful plants from harmful ones.
For example
A herder notices that sick animals chew a particular bark and recover, tries it on a person, and a remedy is remembered long before anyone can explain why it works.
Pause and check yourself
How did early people find helpful plants, despite their beliefs about disease?
Show the answer
By observation, by watching sick animals, by accident and by trial and error, they separated helpful plants from harmful ones.
Read detailed explanations
Why the history lesson is practical
History is not decoration in this course; it explains the shape of modern practice. The move from crude preparations to pure substances is why doses are now written in milligrams rather than “a handful of leaves”. The move to experimental testing is why today’s equivalent of the old pharmacopoeia includes identity, purity and potency tests, and why a modern regulatory agency demands evidence before a drug is sold. The recognition that a drug can act at a named site is why dose–response curves, receptor theory and antidotes exist. Finally, history warns against repeating errors. Older medicines such as thalidomide were released after testing that would not be accepted today; the resulting harm reshaped drug regulation worldwide. When you learn the four clinical trial phases in the next unit, you are learning the modern answer to a very old problem: how to separate a remedy that truly works from one that merely seemed to.
Astrology, clergy and the slow arrival of controls
It is tempting to laugh at early explanations. A better use of them is to notice the same error in modern clothing: a treatment is accepted because it feels meaningful, because an authority recommends it, or because it seemed to work once. The belief that planetary position governed a medicine’s effect is structurally similar to a modern claim that a supplement “works because it is natural”. Both skip the experiment. The historical shift from divine or astrological authority to measured evidence was slow and uneven, and it is still incomplete: many traditions continue to use preparations whose benefit has never been separated from their placebo effect or from recovery that would have happened anyway. This course does not ask you to dismiss traditional medicine; it asks you to state clearly what is known, what is plausible and what is untested, and to label each correctly in your own practice.
Explore the diagram
Look at the whole drawing first. Then select one numbered part and connect it to the idea you just read.
From folk remedy to experimental science
Selected milestones showing how medicines moved from tradition and accident to measured experiment and design.
New to diagrams? Read this first
Look at the whole drawing once without clicking anything. Ask yourself only: what kind of picture is this (a comparison, a route, a sequence, a table)?
Press Play, or use the arrows, to move through the numbered parts in order. The drawing stays still; only the highlight moves.
Click a number, or its name in the list below, to read what that part is and why it matters. Use “Hide labels” when you want to test your memory.
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01 / 5Dioscorides
If the drawing is wider than this panel, scroll it sideways. Labels stay readable; the numbered explanations below show the same ideas.
Dioscorides
A Greek army surgeon whose De Materia Medica is often called the oldest and most valuable work in the history of pharmacology. It collected and studied 600 medicinal plants — an early pharmacopoeia built on observation.
Dates and attributions follow the supplied lecture notes. History is selective here; it is included because each milestone changed how drugs are studied.
Key points to remember
✓Early medicine mixed careful observation with superstition, astrology and religious authority.
✓Pharmacology became a science in the 19th century, when physiologists began testing plant extracts experimentally.
✓Dioscorides, Magendie, Bernard, Buchheim, Schmiedeberg, Abel and Fleming each added a piece of the discipline.
✓Discovery has reversed direction: it once started from a plant, and now often starts from a molecular target.
Go deeper
Worked example
Reading a discovery as a chain of evidence. You are shown the sentence: “In 1842 Claude Bernard discovered that curare acts at the neuromuscular junction.” You are asked to separate the observation, the experiment and the conclusion.
Observation: an animal given curare becomes paralysed but its heart keeps beating — the drug stops movement, not life.
Experiment: stimulate the nerve and the muscle does not respond; stimulate the muscle directly and it contracts.
Conclusion: the block is at the junction between nerve and muscle, not in the nerve or the muscle itself.
Why it matters: a named site of action turns a poison into a tool, and later into a family of muscle relaxants used in surgery.
Historical discoveries are only useful to a beginner when reduced to a testable claim: what was observed, what was changed, and what followed.
Common misconception
A beginner may conclude that medicine advanced mainly through lucky accidents. Accidents such as Fleming’s penicillin matter, but they only become medicine when systematic testing explains and reproduces them.
Check your reasoning
Why does knowing a drug’s site of action, rather than just its effect, make a prescriber safer?
Reveal an answer
Because the site predicts more than the main effect. It predicts which other tissues may be affected, which side effects to expect, how another drug might interfere, and whether an antidote or reversal agent exists.
Where this comes from
BMS 113 General Pharmacology I lecture notes · Unit 1.3, pp. 7–9
Lesson progress is saved on this device for the current learner. Practice answers stay separate and are not stored.
About this course and its sources
Bilingual lessons organised from the supplied BMS 113 General Pharmacology I lecture notes. Diagrams are original educational schematics; pharmacology, nursing and French-language review are pending.