Analgesia

Question 1

Drugs that reduce pain at the site of injury do so how?

Answer 1

Decreases sensitisation by blocking’s prostaglandin synthesis

Question 2

Give a example of a drug that reduces pain at the site of injury?

Answer 2

NSAIDs

Question 3

Drugs that reduce nerve conduction of pain do so how?

Answer 3

Block of voltage gates Na+ channels

Question 4

Give an example of drugs that reduce the nerve conduction to reduce the perception of pain?

Answer 4

Lignocaine

Question 5

List some drugs that reduce the synaptic transmission in the dorsal horn.

Answer 5

Opiods

Some antidepressants

Question 6

List drugs which activate the descending inhibitory controls.

Answer 6

Opiods

Select tri-cyclic antidepressants

Question 7

Which drugs target the ion channels that are unregulated in nerve damage?

Answer 7

Antiepileptics e.g. GABA pentinoids

Question 8

List some common NSAIDs

Answer 8

Aspirin
Diclofenac
Ibuprofen
Naproxene

Question 9

List some weak opiods

Answer 9

codeine
tramadol
dextropropoxyphene

Question 10

List some strong opiods

Answer 10

Morphine
oxycodone
fentanyl
heroin

Question 11

In supra spinal antinociception where do the neurones arise from?

Answer 11

Peraqueductal grey mater
Locus coeruleus
Nucleus Raphe Magnus

Question 12

Where do neurones of the supra spinal anti-nociception project down to?

Answer 12

Posterior horn to the area where the 1st and 2nd order neurones of the spinothalamic tract synapse.

Question 13

The supra spinal antinociception neurones release what into the synapse?

Answer 13

Noradrenaline 
5 HT (Seretonin)

Question 14

Noradrenaline and 5 HT have what affect of the spinothalamic tract?

Answer 14

Inhibits the release of Substance P from presynaptic build.

Prevents Depolarisation on the Second order neurone.

Question 15

What affect does Noradrenaline and 5HT have on the interneurone located by the synaptic cleft of the 1st and 2nd order neurone?

Answer 15

Interneurone is activated and releases Enkephalin (Opiod)

Question 16

What is the affect of Enkephalin?

Answer 16

Prevents depolarisation of the presynaptic bulb and the sport synaptic neurone.

Question 17

What kind of receptors do opioids work on?

Answer 17

G protein Coupled Receptors

Question 18

What is the affect of activating a opioid G protein coupled receptor?

Answer 18

Beta unit - Inhibition of Ca2+ channels suppress excitatory neurotransmitter release.
- opening K+ channels suppressing excitation by hyper-polarising the neurones.
Inhibiting adenyl cyclase - long term suppression

Question 19

What are the different types of opioid receptors and what are there functions?

Answer 19

μ - most analgesic action and major sideaffects
δ - activation can be proconvulsant
k - Sedation dysphoria and hallucination

Question 20

List the major respiratory side effects of Opioids.

Answer 20

Apnoea - medullary respiratory system becomes desensitised to CO2 levels

Question 21

List the major cardiovascular side effects of Opioids

Answer 21

Orthostatic hypotension - reduced sympathetic tone and bradycardia
Histamine mediated dilation

Question 22

List the major GI side effects of Opioids.

Answer 22

Nausea Vomiting Constipation

-acts on the CTZ

Question 23

List the major CNS side effects of Opioids.

Answer 23

Confusion Euphoria Dysphoria hallucinations Dizziness Myoclonus Hyperalgesia

Question 24

Morphine

Answer 24

Acute and Severe pain
Metaboised in liver
IV IM SC or oral

Question 25

Diamorphine

Answer 25

Severe post operative pain More lipophilic than morphine Rapid onset when IV Heroin

Question 26

Codeine

Answer 26

Mild moderate pain Anti diarrhoea Antitussive (prevent cough) Oral

Question 27

Fentanyl

Answer 27

75x more potent than morphine IV to provide analgesia in maintenance anaesthesia Transdermal or buccal in chronic pain

Question 28

Pethidine

Answer 28

Acute pain especially labour Rapid onset IV IM or SC - short duration Should be given with MAO inhibitors

Question 29

Buprenophine

Answer 29

Useful in chronic pain with patient controlled injection system Slow onset but long duration of action

Question 30

Tramadol

Answer 30

Weak μ agonist Oral Avoid in patients with epilepsy

Question 31

Methadone

Answer 31

Chronic pain and cancer Assisted withdrawal from heroine Long duration of action

Question 32

What is the purpose of Antagonist to Opioid receptors?

Answer 32

Used to reverse opioid toxicity

Question 33

List some opioid antagonists

Answer 33

Naloxene Naltrexone Alvimopan

Question 34

Naloxene

Answer 34

Incrementally IV IM or SC Short half life - careful monitoring Can induce acute withdrawal symptoms Used in new borns with opioid toxicity

Question 35

Naltrexone

Answer 35

Oral availability and longer half life

Question 36

Alvimopan

Answer 36

No affect of CNS | Reduced GI affects of chronic opioid use.

Question 37

NSAIDs

Answer 37

Prevent prostaglandin build up by inhibition of COX enzyme.

Question 38

What drugs are used for neuropathic pain

Answer 38

Gabapentin | Pregablin

Question 39

What is the action of gabapentin an pregablin?

Answer 39

Reduced voltage gated Ca2+ channel expression | Decreases neurotransmitter release

Question 40

What is gabapentin used for?

Answer 40

Migraine prophylaxis

Question 41

What is pregablin used for?

Answer 41

Useful in painful diabetic neuropathy

Question 42

How do Tricyclic antidepressants like Amitriptyline work?

Answer 42

Decrease the re uptake of neurotransmitter noradrenaline

Question 43

What is the first line drug for trigeminal neuralgia?

Answer 43

Carbamezapine

Question 44

How does Carbamezapine work?

Answer 44

Block Na+ voltage gated ion channels