Opiates

Nature of science:

Data and its subsequent relationships—opium and its many derivatives have been used as a painkiller in a variety of forms for thousands of years. One of these derivatives is diamorphine. (3.1)

• The ability of a drug to cross the blood–brain barrier depends on its chemical structure and solubility in water and lipids.
• Opiates are natural narcotic analgesics that are derived from the opium poppy.
• Morphine and codeine are used as strong analgesics. Strong analgesics work by temporarily bonding to receptor sites in the brain, preventing the transmission of pain impulses without depressing the central nervous system.
• Medical use and addictive properties of opiate compounds are related to the presence of opioid receptors in the brain.

Applications and skills:

• Explanation of the synthesis of codeine and diamorphine from morphine.
• Description and explanation of the use of strong analgesics.
• Comparison of the structures of morphine, codeine and diamorphine (heroin).
• Discussion of the advantages and disadvantages of using morphine and its derivatives as strong analgesics.
• Discussion of side effects and addiction to opiate compounds.
• Explanation of the increased potency of diamorphine compared to morphine based on their chemical structure and solubility.

Guidance:

• Structures of morphine, codeine and diamorphine can be found in the data booklet in section 37.

• Many illegal drugs are cultivated or produced in a small number of countries and then sold and distributed globally. Cultural and economic viewpoints differ on the production and sale of opiates around the world.

Theory of knowledge:

• Cultures often clash over different perspectives and ideas. Is there any knowledge which is independent of culture?

Utilization:

• Syllabus and cross-curricular links:
• Topic 10.2—functional groups

Aims:

• Aim 7: Use computer animations for the investigation of 3-D visualizations of drugs and receptor sites.