Morphine Flashcards
1
Q
Class
A
Opioid receptor agonist
2
Q
Actions
A
Analgesia Sedation Euphoria Reduced anxiety Physical/psychological dependence Cough suppression Respiratory depression Increased gut motility
3
Q
Mechanism of action
A
Activates u opioid receptors in brain and spinal cord to inhibit pain transmission and modify central perception of pain May inhibit sensory nerve ending activation Opioid receptors are G- protein coupled receptors Open K+ channels and inhibit opening of Ca2+ channels in nerve endings
4
Q
Clinical use
A
Moderate to severe chronic and post- operative pain Epidural anaesthesia Neuropathic pain Treatment of painful cough Diarrhoea
5
Q
Adverse effects
A
Hypotension Tolerance, dependence and withdrawal effects Larger dose can lead to a coma with respiratory depression
6
Q
What is Morphine
A
An analgesic (An opiate agonist)
7
Q
what opiate receptors does morphine bind to
A
The mu-opioid receptors
The GABA inhibitory interneurons
8
Q
Morphine and the mu-opioid receptors and the mechanism of respiratory depression
A
involves a reduction in the responsiveness of the brain stem respiratory centres to increases in carbon dioxide tension and to electrical stimulation
9
Q
and the GABA inhibitory interneurons.
A
Morphine inhibits the activity of the GABA inhibitory interneurons and therefore limits the descending pain inhibition pathway
10
Q
what happens as a result of the lack of inhibitory signals
A
pain modulation can proceed downstream
