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What causes pain and how do we stop it? This free course, Pain and Aspirin, looks at how the human body responds to the release of certain chemicals and as a result feels pain. Pain can be reduced by inhibiting the formation of such chemicals and you will learn how the molecular structure of aspirin has been formulated to help in this process.
After studying this course, you should be able to:
- demonstrate general knowledge and understanding of some of the basic facts, concepts and principles relating to the development of medicines
- demonstrate knowledge and understanding of the science behind the development of some drugs to achieve particular tasks
- demonstrate knowledge and understanding of how chemical bonding determines the properties of compounds and provides an explanation for the mode of action of drugs
- apply this knowledge and understanding to address familiar and unfamiliar situations
- express unit concepts in an objective and factually correct way.
- Learning outcomes
- 1 Ouch – that hurts!
- 1.1 Why does it hurt?
- Current section: 1.2 How does it hurt?
- 1.3 The aspirin story
- 1.4 The molecules involved
- 1.5 Some chemistry involving esters
- 1.6 How does aspirin relieve pain?
- 1.7 Enzymes
- 1.8 Enter aspirin!
- Keep on learning
Study this free course
Enrol to access the full course, get recognition for the skills you learn, track your progress and on completion gain a statement of participation to demonstrate your learning to others. Make your learning visible!
1.2 How does it hurt?
This is a useful question because once we know the mechanism of pain sensation we can do something about alleviating it.
When tissue is injured there follows a rapid release of ‘messenger’ chemicals that stimulate the nerve endings. Electrical impulses are relayed through the nerves to the spinal column and to the brain, which registers the sensation of pain. It usually, but not always, also directs our attention to the site where the damaged tissue initiated the pain message.
Drugs to alleviate pain act to interrupt this flow of information. There are three basic types grouped together by the way in which they work.
Drugs such as aspirin act at the site of the injury to stop or at least reduce the production of messenger chemicals that stimulate the nerve endings.
Another class of drugs, the opiates such as codeine and morphine, act on the central nervous system (brain and spinal cord). Sometimes, the aspirin-like and codeine/morphine-like drugs are combined into one remedy, for example co-codamol and co-proxamol.
For the time being, we will concentrate on aspirin, to illustrate the development of drugs and how they are able to achieve their effects.
Copyright & revisions
Originally published: Thursday, 24th March 2016
Last updated on: Thursday, 24th March 2016
- Creative-Commons: The Open University is proud to release this free course under a Creative Commons licence. However, any third-party materials featured within it are used with permission and are not ours to give away. These materials are not subject to the Creative Commons licence. See terms and conditions. Full details can be found in the Acknowledgements and our FAQs section.
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