Palliative Drugs Flashcards
Four palliative drugs
- Morphine (pain)
- Haloperidol (nausea)
- Midazolam (agitation)
- Hyoscine butlybromide/Buscopan (secretions)
Nausea and vomiting
https://www.bmj.com/content/351/bmj.h6249.abstract
Opioid toxicity.
a) 3 cardinal signs
b) Other signs
c) If patients have opioid toxicity due to increasing renal impairment, what should you do?
d) Indications for naloxone
a) - Visual hallucinations (eg. shadows over their shoulders)
- Drowsiness
- Myoclonic jerks (eg. spilling tea over themselves)
b) - Pinpoint pupils
- Respiratory depression
c) Switch from morphine/oxycodone to alfentanil, fentanyl or methadone
d) - RR<8, AND
- Oxygen sats <92%
WHO analgesic ladder.
a) Step 1
b) Step 2
c) Step 3
d) What should be co-prescribed at steps 2 and 3?
a) Paracetamol, NSAIDs
+/- adjuvants (anti-epileptics)
b) Weak opioids (eg. codeine, dihydrocodeine, tramadol)
+/- paracetamol, NSAIDs
+/- adjuvants
c) Strong opioids (eg. morphine, oxycodone, fentanyl, buprenorphine)
+/- paracetamol, NSAIDs
+/- adjuvants
d) Laxatives
- maybe also anti-emetic (eg. haloperidol)
Opioid conversion.
a) Codeine/tramadol to morphine (eg. 250 mg codeine)
b) Oral morphine to SC morphine
c) Oral morphine to oral oxycodone
d) Oral oxycodone to SC oxycodone
a) Divide by 10 (240 mg codeine = approx. 24 mg morphine)
b) Divide by 2 (10 mg oramorph = 5 mg SC morphine)
c) Divide by 2 (10 mg oramorph = 5 mg SC oxycodone)
d) Divide by 2 (10 mg oral oxycodone = 5 mg SC oxycodone)
Opioid titration.
a) Calculating 24-hour opioid requirement
b) How should it be administered? (to cover background pain)
c) Breakthrough pain - how to calculate PRN dose
a) - Stabilise pain on regular 4-hourly OralMorph + PRN
- Calculate total dose given over previous 24 hours (regular plus PRN)
b) Administer in divided doses as twice daily Modified Release Morphine - covers background pain
(Total 24-hour requirement divided by 2)
c) PRN dose = approx. 1/6th of total 24h requirement
Opioid patches.
a) Fentanyl
- patch duration, risks
b) Buprenorphine
- patch duration, benefits
c) Indications
d) Why not used in acute pain?
e) What should you check?
a) Change patch every 72 hours
- do not use as first line opiate - risk of respiratory depression
b) Two types: weekly or bi-weekly patches
- roughly equipotent to fentanyl
- less chance of opioid-induced hyperalgesia compared with fentanyl
- also comes in a lower dose preparation - better for patients who have been on weak opioids
c) In opioid-responsive stable pain where there is…
- Poor side effects on oral opioids
- Inability to take oral meds
- Renal failure
d) Take 1 - 3 days to reach therapeutic concentration
e) - Patches are adherent - on non-hairy skin
- No irritation
75 year old lady with metastatic lung cancer is taking codeine 60 mg QDS and paracetamol 2 g QDS, which is not controlling her pain.
a) What should you do?
b) Calculate the appropriate dose
a) - Escalate from weak opioid to strong opioid.
- Continue with paracetamol
b) Codeine to morphine:
- 60 mg codeine QDS = 240 mg codein in 24 h period
- 240 / 10 = 24 mg (morphine requirement in 24 h)
- Start 10 mg BD modified-release morphine
- PRN dose oramorph ~ 4 mg
Types of pain.
a) Background pain
b) Breakthrough pain
a) Pain at rest, ongoing pain
b) Transient exacerbation
- Can be predictable (eg on movement) or unpredictable
83 year old man with metastatic thyroid cancer is taking morphine MR 10 mg BD, but is becoming nauseous, itchy and constipated.
a) What could you switch him to?
b) What dose?
a) Switch to oxycodone (less side effects)
b) - On 10 mg MR morphine BD = 20 mg per 24 h
- Oral oxycodone is 2x more potent than oral morphine
- Switch to 5 mg oxycodone BD
Opioids and driving.
- If a patient is on a stable dose of opioids and not impaired, they can drive.
However, the advice is to not drive if….
- the patient’s dose has recently increased
- or if they have just had a PRN dose
Opioids and renal failure.
a) Which are worst in renal failure?
b) Switch to what opioids?
a) Morphine (avoid), then oxycodone (avoid if GFR < 10)
b) Alfentanil, methadone
these are only used in palliative care
Bone pain: treatments
- Bisphosphonates
- NSAIDs (+ PPI)
- Radiotherapy (multiple sites)
- Surgery (single site)
Opioid induced hyperalgesia.
a) What is it?
b) Features
a) Increasing pain associated with rapidly escalating opioid doses.
b) Change in pattern of pain, becoming more diffuse and associated with:
- hyperalgesia,
- allodynia
- myoclonus.
- When severe: delirium, fits, coma and death
Serotonin syndrome.
a) Drug causes
b) Features
c) Biochemical findings
d) Management
a) SSRIs, SNRIs, TCAs, metoclopramide, ondansetron
- tramadol, fentanyl, methadone
b) MAD:
- Mental state altered: anxiety, agitation, confusion, coma
- Autonomic disturbance: high temp, BP and HR
- Neuromuscular dysfunction: tremor, clonus and hyperreflexia
c) ?
Neuroleptic malignant syndrome.
-
Raised ICP.
a) Initial management
b) If seizure
a) 8mg BD dexamethasone
b) Levetiracetam
Constipation in palliative care.
a) Identifying cause
b) Non-drug measures
c) If these fail -?
d) Persistent/impaction - ?
a) - Consider cause (eg. hypercalcaemia, obstruction)
- Perform PR
b) - Non-drug measures (eg. fluids, fibre)
c) - 1st line: stimulant (eg. Senna) + softener (eg. docusate)
d) - Persistent/impaction: enemas, suppositories, macrogols
Treatment of colic
Hyoscine butylbromide (anti-motility)
Breathlessness.
a) Conservative measures
b) Drugs
c) If lots of secretions also
a) Fan (as good as oxygen if not hypoxaemic)
- Oxygen, ventilation
b) - Morphine
- Lorazepam if associated with anxiety
c) Hyoscine butylbromide (Buscopan)
Agitation/restlessness.
a) If predominantly anxious
b) If hallucinations, delirium, etc.
c) Management of psychosis in PD
a) Benzo - midazolam/ lorazepam
b) - Antipsychotic - haloperidol
- Nurse in well-lit environment, orientate, etc.
c) - In PD - reduce PD meds if possible, and treat any other precipitants (eg. anticholinergics)
- If drugs needed - consider 2nd gen (eg. clozapine, quetiapine)
Nausea and vomiting.
a) Consider causes
b) 1st line and alternatives
c) 1st line in PD
a) Opioids, bowel obstruction, hypercalcaemia, etc.
b) Haloperidol; levomepromazine, metoclopramide
- all are contraindicated in PD
c) - Domperidone, cyclizine, or ondansetron
Anti-emetics: MoA and indication.
a) Cyclizine
b) Haloperidol
c) Metoclopramide
d) Domperidone
e) Dexamethasone
f) Ondansetron
a) H1-antagonist (anti-histamine):
- good for general and vestibular nausea
- also useful in pregnancy - morning sickness and HG
b) D2-antagonist (antipsychotic):
- good for central causes and cancer-associated nausea, 1st line in palliative care
- beware Parkinsonian side effects (EPSEs)
c) D2-antagonist, and 5-HT3/5-HT4, and muscarinic:
- good for central causes and ProKinetic (good for constipation)
- beware Parkinsonian side effects (EPSEs)
d) Peripheral D2-antagonist
- hence can be used in PD (as does not cross BBB in large amounts)
e) Corticosteroid
- useful in vomiting associated with chemotherapy
f) Serotonin (5-HT3) antagonist
- useful in chemotherapy associated diarrhoea and vomiting
Betty is on morphine M.R. 50mg BD and oramorph 15mg PRN. She is approaching the end of life.
a) What should you do?
b) Work out the her 24-hour requirement and hence the necessary dose for background pain
c) What should her PRN dose be?
d) If stable on fentanyl patch but needing to start a syringe driver, should you remove patch?
a) Switch to syringe driver - SC morphine
b) - 50 mg BD = 100mg oral morphine per 24 hours for background pain control
- Oral to SC morphine = divide by 2
- 100 / 2 = 50
- Background dose: 50 mg morphine SC over 24 hours (via syringe driver)
c) - Oral to SC morphine = divide by 2
- 15 / 2 = 7.5
- PRN dose = 15 / 2 = 7.5 mg SC morphine
d) No.
Keep patch on and use it in calculation of opioid requirement
