Analgesics Flashcards
What is the meaning of Emesis?
The action or process of vomiting
What antidepressants are used in analgesia?
- Selective serotonin re-uptake inhibitors (SSRIs):
- Paroxetine, Citalopram, Fluoxetine, Sertraline
- Serotonin and Noradrenaline re-uptake inhibitors (SNRIs):
- Venlafaxine
What anti-epileptics are used in analgesia?
- Carbamazepine
- Gabapentin
What anaesthetics are used in analgesia?
- Lidocaine
- Ketamine
What opioids are used in analgesia?
- Purinie Agonists
- Morphine-like dugs
- Partial Agonists
- Nalorphine, Pentazocine, Cyclazocine
- Antagonists
- Naloxone, Naltrexone
How do antidepressants work for analgesia?
- SSRI - Paroxetine, Citalopram, Sertraline, Fluoxetine
- Not paticulary effective for analgesia
- Appear to work well in disease environment such as diabetes or HIV related neuropathy
- Both prevent the recycling of neurotransmitters and enhance signal
- SNRI - Duloxetine, Venlafaxine
- Highly effective for neuropathic pain
- Side effects - nausea, somnolence, insomnia, dizziness, sedation, headache
What are the contradictions and interactions for antidepressants in the use of analgesia?
Contradictions - epilepsy, cardiac disease, diabetes, glaucoma, pregnancy/breast feeding
Interactions - alcohol (increased sedation), NSAID/Aspirin (incrased risk of CNA toxicity), increased in sedaive effectiveness when given with opioid analgesics and SSRIs antagonise anticonvulsant effects of antiepilptics
How do antiepileptics work in anaglesia?
- Inhibit voltage fated Na+ and Ca+ channels
- Inhibit glutamine, GABA and gylcine receptors
- Inhibit action potential firing
- Prevent impulse transmission
- Limit neuronal excitation
How does carbamazeoine work in analgesia? (antiepileptics)
Fror glossopharyngeal neuralgia, post-herpetic neuralgia, trigeminal neuralgia and diabetic neuropahies
SIDE EFFECTS - dizziness, diplopia, drowiness, fatigue, nausea, hepatitixicty, renal impairment, skin reactions, anorexia, dyspepsie, tremor
Caution/contradicitions - hepatic/renal impairment, cardiacc disease, skin reactions, glaucoma, pregnancy, history or bone marrow depression
How does Gabapentin work in analgesia? (antiepileptics)
Complex regional pain syndrome, neuropathy of the face, post herpatic neuralgia, sciatic type of pain neuropathy
SIDE EFFECTS - anorexia, dyspepsia, tremor
Cautions/contradications - elderly, renal impairment, diabetes, pregnancy
How is Lidocaine used in anaglegsia? (LA)
Na+ channel blocker - effective in non-cancer patients (IV)
SIDE EFFECTS- CNA effects (confusion), respiratory depression, convulsions, hypotension, bradycardia
Cautions/contradictions- Epilepsy, hepatic/respiratory impairment, AF, heart block, heart failure
How is Ketamine used in analgesia? (anaesthetic)
Block glutamine receptors
- Injectible but not favoured due to side effects
- SIDE EFFECTS - hypertension, tachycardia tremor, diplopia (double vision) myocardial depression
- Caution/contradications - hypertension, angina, heart failure, aneurysms, cerebral trauma, psychotic disorders
How do opioids work in analgesia?
- modify the transmission of pain signals and the subjective perception of pain
- decrease neurotransmitter release
- block postsynaptic receptors
- activate inhibitory pathways
- highly effective - variety of routes
- SIDE EFFECTS- N+V, consitpation, respiratory depression, hypotension, sedation
- Caution/contradictions - acute respiratory depression, acute alcholism, head injury
- INTERACTIONS - alcohol (increass hypotensive an sedative effects), MAOI (increased CNA excitation/inhibition), SSRI/TCA (increase sedation), Carbamazepine (decreased plasma concentration of methadone), Cimetidine (ulcer healing - inhibit opioids metabolism)
Which of the followng antiemetic drugs is the “drug of choice” for the treatment of Post-operative nausea and vomiting (PONV) and cheotherapy-induced nausea and vomiting (CINV) ?
Ondansetron
Which of the following is NOT associated with emesis?
The sympathetic pathway