Overview of Pharmacology

  • What is pharmacology now and how did it begin?
  • What are drugs?
  • What are the major area’s of pharmacology?
  • Drug discover and design through to approval and regulation


Pharmacology is a branch of medicine concerned with drug structure, drug targets and effects of drugs on living systems. A drug has to have a known structure and must also have an effect on a living system – this effect can be biochemical or physiological. Drugs can be artificial (made by humans), natural (found in nature – usually refined or purified for consumption), however, they have to be exogenous (not originating from or made outside of the organism it is acting on). Another way to classify drugs is chemicals plant/animal/synthetic derived molecules or biologicals which are antibodies/cytokines/etc

The three types of drugs include; medicines – these have known therapeutic effects, experimental tools – these do not have therapeutic effect, illicit drug – drugs which are abused or addiction. Note some medicines can become illicit drugs if the drug is abused.

Pharmacology is a science, this means it draws its conclusions from empirical observations. Prior to pharmacology herbal remedies, heavy metal treatments and other dangerous concoctions were used to treat disease. This meant pharmacology emerged out of the need of medicine to treat disease – since the existing treatments physicians had on had likely killed the patients if the disease didn’t.

Pharmacology started in the 1800s through the study of natural product derivide medicines, it was latter advanced through synthetic chemistry. This allowed medicinal chemists and pharmacologists to tweak the design of existing drugs and create new ones. Acetylsalicyclic acid (sold under brand name aspirin) is used to reduce pain, fever or swelling and is the first synthetic drug developed.

The future of pharmacology will see patients genomes being used to predict and optimize what drug to prescribe – a more personalized approach. This will minimize side effects and maximize effectiveness.

The four major areas of pharmacology are:

  • Pharmacodynamics – the study of the biochemical and physiological effects of a drug on a system.
  • Pharmacokinetics (PK) – the study of the systems effect on the drug – how is it administrated? How long does it take to be absorbed? What route is it distributed? What happens to it as it is metabolized and removed from the body?
  • Systems Pharmacology – applying systems biology to pharmacology to understand the effect of the drugs on a complex system
  • Drug design and development – finding and refining potential leads to treat a disease

The process from iteration of a drug to a new clinical drug involves finding drug leads – these are usually a starting point and it may be based on a molecules particular affinity to a target. Potential targets for drugs will be covered in more depth next lesson. Leads can come from natural products, random screening, high throughput screening, changing existing known molecules, in silico docking, etc. Following this pre clinical experiments test for potential side effects and determine also determine its potency. Clinical trials start by looking at safety then effecacy in small population followed by a large population. Then the drug is approved and continually regulated – a process which can cost over 1 billion.



Question 1. [1 mark]

Define what a drug is.

Question 2. [Not exam style question]

Define what pharmacology is and it’s main areas.

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