Discuss the pharmacology, therapeutic uses and side effects of opioids Flashcards
What are the main 4 functions of Mu receptos?
- analgesia
- euphoria
- constipation
- respiratory depression
What are the main 3 functions of kappa opioid receptors?
- analgesic at periphery
- dysphoria
- hallucinations
What morphine effect is caused from reduced motility and muscle tightening?
constipation
How does morphine treat nausea and vomiting?
by chemoreceptors triggering a zone in the medulla
How is tolerance caused by recurrent opioid use?
- desensitisation of Mu receptors
- increasing doses needed to achieve sufficient analgesia
What is a side effect of chronic opioid use?
constipation
What are signs of physical opioid dependence/withdrawal?
- restlessness
- agression
- runny nose
- diarrhoea
What are 3 opioid receptor antagonists?
- naloxone
- methylnaltrexone
- naltrexone
How does treat cause pupillary constriction?
by stimulating the oculomotor nucleus brainstem
What are 8 therapeutic uses of opioids?
- analgesia
- sedative
- treatment of diarrhoea
- treatment of cough
- euphoria
- pupillary constriction
- nausea + vomiting
- respiratory depression
How does morphine treat cough?
by suppressing the cough reflex
Where is morphine metabolised and excreted?
- metabolised in the liver
- excreted in urine
How does naloxone work, how is it given, and what is one adverse side effect
- reverses opioid actions on Mu receptor
- given IV/SC in acute opioid toxicity
- can trigger acute physical withdrawal
What is the main function of delta opioid receptors?
analgesia at spine
What are opioid peptide receptors, what do they do, and where are they distributed?
- G-protein coupled
- opens K+ channels
- closes Ca+ channels
- widely distributed in the CNS and GI tract
