Analgesics Flashcards
Parasthesis is painful feelings…
With no apparent stimulus (eg. Pins and needles)
Allodynia is pain from
A stimulus that doesn’t usually cause pain
Short term pain, with an easily identifiable cause. A warning of present tissue damage or disease which respond well to medication is known as
Acute/nociceptive pain
Pain which persists, is constant or intermittent and has outlived its purpose since it no longer helps the body to prevent further injury is known as
Chronic/neuropathic pain
Which is easier to treat using analgesia nociceptive or neuropathic pain?
Nociceptive
The pain pathways is linked to which tract?
Spinothalamic tract
What intensifies the sensation of pain and the pain pathway?
Inflammation
In the pain pathway inflammation intensifies the pain, which drugs could be given to control the inflammation and therefore dampen down the pain signals
NSAIDs and paracetamol
Anti inflammatory actions of steroids
Where in the brain is the ‘perception of pain’
Thalamus
Where in the brain is the pain localised?
Somatosensory cortex
Where in the brain is the behavioural and emotional side of pain
Hypothalamus limbic system
Where in the brain is the ‘alertness’ associated with pain interpreted
Reticular formation in the brain stem
True or false, we have our own endogenous pathways to responding to pain, drugs enhance these
True
Which analgesics modify the transmission of pain signals and the subjective perception of pain
Opioids
Which analgesics are effective for neuropathic pain which is resistant to opioids?
Antidepressants, anti epileptics
Which type of analgesics are effective for trigeminal neuralgia
Anti epileptics; carbamazepine
Which type of analgesic is particularly effective for severe intractable or crescendo neuropathic pain: emergency medicine
Local anaesthetics
Neuropathic pain is often resistant to anaesthetics, true or false
True
Which of the following chemicals may be classed as pain modulators; Noradrenaline Enkephalins Histamine Bradykinin
Enkephalins
Histamine
True or false, Mu-opioid receptors are responsible for relatively few side effects
False
Mu-opioid receptors may elicit sedation and dysphoria, true or false
False
True or false, opioids interact with cimetidine (drug for ulcer treatment)
True
True or false, acute pain is pain that has lasted for 6months or longer
False
True or false, chronic pain is constant or intermittent pain that does not help the body prevent injury
True
Which analgesics work at spinal cord and CNS level, decreasing neurotransmitter release and blocking post-synaptic receptors, and activating inhibitory pathways
Opioid analgesics
What are some com in side effects of opioid analgesics
Nausea, vomiting, constipation, drowsiness, resp depression, hypotension, dependency
What are the cautions/contraindications of using opioids
Acute respiratory depression
Acute alcoholism
Head injury
Opioid analgesics interact with alcohol, what effects can be seen
Increased hypertensive and sedative effects
Opioids interact with MAOIs what effect can be seen
Increases CNS excitation/inhibition
Opioids interact with SSRI/TCAs what effect can be seen
Increased sedation
Opioids interact with the drug carbamazepine, what effect can be seen
Decrease in the plasma concentration of methadone
Opioids interact with the ulcer healing drug cimetidine, what happens
Inhibits opioid metabolism
What are the 3 types of opioid receptors
Mu, Kappa, delta
Most analgesic opioids are agonists of which opioid receptor
Mu
Which analgesics mimic our endogenous ligands (enkephalins)
Opioids
Which opioid receptors are found in the CNS and peripheral sensory neurons and don’t have a major contribution to the pain pathways?
Delta
Which opioid receptors are found only in the CNS, spinal cord and peripheral sensory neurons
Kappa
Which opioid receptors are responsible for the sedation and dysphoria side effects seen with opioid analgesics
Kappa
Which opioid receptors are responsible for opioid dependence
Mu
Which opioid receptors are found in the CNS, spinal cord, peripheral sensory neurons and GI tract
Mu
Which opioid receptors are responsible for most of the side effects seen with opioid analgesics
Mu
Which opioid receptors are responsible for most of the analgesic effects
Mu
True or false, opioid antagonists have strong analgesic actions
False, opioid antagonists have no analgesic properties, they are used in the treatment of heroine/morphine overdose
The opioid analgesic morphine can be used for which pain
A. Chronic
B. Acute
C. Both
Both
What is the half life of morphine
3-4 hours
How can morphine be administered
Oral
IV
Intrathecally
Subcutaneously
True or false, diamorphine is more rapidly metabolised than morphine
True
How can diamorphine be Administered
Oral
IV
What are the side effects of morphine, diamorphine and fentanyl
Sedation. Tolerance
Resp depression. Dependence
Constipation. Euphoria
N & V
Itching
How is the opioid hydromorphine administered
Oral
IV
What is the half life of hydromorphine
2-4 hours
How many more times effective is hydromorphine than morphine
6 fold
Which opioid drug is only indicated for chronic pain?
Methadone
What is the half life of methadone
> 24hours
How is methadone administered
Oral
IV
Which two opioids cannot be administered orally?
Buprenorphine and fentanyl
Which opioid analgesic is indicated for acute, intense pain
Pethidine
How can the opioid analgesic Pethidine be administered
Oral
IV
Intramuscular
Which two opioid analgesics are indicated for mild pain
Codeine
Dextropropoxyphene
Which opioid analgesic causes the side effects of mainly constipation and has no dependence liability
Codeine
Which opioid analgesic is a pro drug, metabolised to morphine once ingested
Codeine
Which opioid analgesic is indicated for acute & chronic pain, rheumatoid arthritis, restless leg syndrome, motor neurone disease and fibromyalgia
Tramadol
What is the half like of Tramadol
4-6 hours
Which analgesics work only upon endogenous inhibitory pathways
Antidepressants
Which type of antidepressants are highly effective for neuropathic pain
Serotonin and noradrenaline re uptake inhibitors
Venlafaxine and duloxetine are examples of what type of analgesic
Antidepressant - serotonin and noradrenaline reputable inhibtors
SSRI are not particularly effective analgesics but may be effective in some cases, such as what?
Diabetic or HIV-related neuropathy
Paroxetine and citalopram are examples of what kind of analgesics
Antidepressants, SSRIs
How do SNRI/SSRIs work as analgesics
Prevent the reputable of neurotransmitters, enhancing their signal which inhibits pain pathway in brain
The SNRI antidepressants duloxetine and Venlafaxine are prescribed as analgesics for pain associated with what?
Diabetic neuropathy
Which SNRI antidepressant causes the following side effects;
Nausea, somnolence, insomnia, dizziness
Duloxetine
Which SNRI antidepressant causes the following side effects;
Nausea, sedation, headache and dizziness
Venlafaxine
Which drugs are contraindicated for the following?
Epilepsy, cardiac diseases, angle closure glaucoma, pregnancy/breast feeding
SNRIs duloxetine and Venlafaxine
Opioid analgesics interact with the SNRIs duloxetine and Venlafaxine increasing what?
The sedative effect
Tramadol interacts with the SNRIs duloxetine and Venlafaxine increasing what
Increasing CNS toxicity
NSAIDs/aspirin interact with the SNRIs duloxetine and Venlafaxine how?
Increase risk if bleeding
Which analgesics work by inhibiting ion channels, decreasing electrical activity suppressing the pain pathway
Anti epileptics
Which ion channels do anti epileptics inhibit which makes then effective analgesics
Inhibit voltage gated Na channels and Ca channels
True or false, anti epileptics inhibit glutamine, aminobutyric acid (GABA) and glycine receptors
False, they inhibit glutamate, GABA and glycine receptors
Which anti epileptic drug works well as an analgesic against the following pain;
Glossopharyngeal neuralgia, post herpetic neuralgia, trigeminal neuralgia and diabetic neuropathies
Carbamazepine
Which anti epileptic drug works well as an analgesic for various neuropathic pain states; complex regional pain syndrome, deafferentiation neuropathy of the face, post herpetic neuralgia, sciatic type pain, neuropathy
Gabapentin
How do local anaesthetics work as analgesics
Inhibit Na channels, preventing nerve transmission
Lidocaine and ketamine are examples of what type of analgesic
Local anaesthetic
Which type of analgesic is particularly effective for severe intractable or crescendo neuropathic pain: emergency medicine
Local anaesthetics
Which patients is lidocaine not effective as an analgesic
Cancer patients
How is lidocaine administered as an analgesic
IV
