Revision - Anticipatory Meds Flashcards
What dose of Morphine sulphate is typically given for opiate naïve patients in end of life care?
1 - 2.5mg SC
Do not repeat within 1 hour
Max 4 doses in 24h
If there is reduced renal function (eGFR <50), what can be used as an alternative to morphine sulphate in end of life care?
Oxycodone 1-2mg SC
Opioid conversion
The following table shows dose equivalents of 10mg oral morphine:
Codeine/tramadol oral –> 100mg
Morphine IM/IV/SC –> 5mg
Oxycodone oral –> 5mg
Diamorphine IM/IV/SC –> 3mg
Conversion factor from oral morphine to SC morphine?
Divide by 2
Conversion factor from oral morphine to oral oxycodone?
Divide by 1.3-2 (depends on trust guidelines)
If in doubt, always opt for the lower dose and titrate up.
It is also possible to use opioid patches for background analgesia. What 2 opioid patches are used?
1) fentanyl
2) buprenorphine
When increasing the dose of opioids, what should the next dose be increased by?
30-50%
How do the side effects of oxycodone differ from morphine?
Oxycodone causes less sedation, vomiting & pruritus but more constipation
What medications can be given for N&V in palliative care?
(4)
1) cyclizine
2) haloperidol
3) levomepromazine
4) metoclopramide
1st line pharmacological management (anti-emetic) of reduced gastric motility N&V in palliative care?
1) Metoclopramide
2) Domperidone (consider use in patients with PD)
When is Metaclopramide NOT indicated in reduced gastric motility N&V in palliative care?
Should not be used when pro-kinesis may negatively affect the GI tract, particularly in complete bowel obstruction, GI perforation, or immediately following gastric surgery.
What class of drug is metoclopramide?
D2 receptor antagonist
Mechanism of action of metoclopramide?
1) Antiemetic effects –> dopamine D2 antagonist in the chemoreceptor trigger zone (CTZ) in the brain. This relieves the symptoms of N&V
2) Increased gastric emptying
Which anti-emetic is used in toxic/chemically mediated N&V in palliative care?
(2)
1) Haloperidol
2) Cyclizine
Which anti-emetic is used in management of cerebral causes of N&V in palliative care?
(2)
1) Cyclizine (if raised ICP)
2) Dexamethasone
Which anti-emetic is used in management of anxiety/anticipatory nausea in palliative care?
Benzos e.g. lorazepam
1st line choice of anxiolytic (for agitation) in palliative care?
Haloperidol
In the terminal phase, what is agitation of restlessness best treated with?
(i.e. anticipatory meds)
Midazolam
2.5 – 5mg SC.
Do not repeat within 1 hour, maximum 4 doses in 24 hours.
anticipatory medications used for respiratory tract secretions?
1) hyoscine butylbromide: 20mg SC
2) hyoscine hydrobromide
3) glycopyrronium
Mechanism of hyoscine butylbromide?
Anticholinergic effect
What are 2 indications for the use of a syringe driver in patients nearing the end of life?
1) requiring 2 or more doses of any one of the anticipatory medications in a 24 hour period
2) being unable to take oral meds that need replacing
What 2 groups can pain be broadly split into?
1) Nociceptive
2) Neuropathic
What is nociceptive pain?
Pain caused by damage to body tissue
What are the 2 types of nociceptive pain?
1) somatic (skin, muscle, bones)
2) visceral (internal organs)
What is neuropathic pain?
Direct damage to nerve tissue (peripheral or central)
What are adjuvant analgesics?
1) Neuropathic agents –> amitriptyline, pregabalin, gabapentin
2) Corticosteroids
3) NSAIDs
4) Non-pharmalogical –> TENS, radiotherapy, acupuncture, heat
Give 3 administration options for the regular background opioid
1) Oral modified release 12 hours (BD) e.g. MST, zomorph
2) 24h syringe driver
3) Transdermal patch e.g. fentanyl, buprenorphine
What is usual starting dose of a strong opioid?
5-10mg modified release morphine
Are opioids a cause of pruritus?
Yes
How are opioids excreted?
Renally
Caution prescribing in renal impairment due to increased risk of opioid accumulation and subsequent toxicity
For patients with renal impairment, what opioid is preferred? Why?
Oxycodone - primarily metabolised by liver
In patients with mild renal or hepatic impairment, how should an opioid dose be changed?
Doses should be reduced by 50%
Specialist advice should be sought before prescribing strong opioids for patients with moderate to severe renal or hepatic impairment.
Are opioids safe in breastfeeding?
No
Max paracetamol dose in 24h?
4g
What 3 classes of drugs can interact with NSAIDs and increase risk of bleeding?
1) Anticoagulants (e.g. warfarin)
2) Antiplatelets (e.g. aspirin)
2) SSRIs (e.g. sertraline)
How do NSAIDs affect the kidneys?
1) sodium levels
2) potassium levels
Can decrease renal function and lead to:
1) hyponatraemia
2) hyperkalaemia
What 2 classes of drugs can interact with NSAIDs and increase risk of electrolyte imbalances?
1) ACEi –> increased risk of hyperkalaemia
2) Diuretics e.g. spironolactone (increased risk of hyponatraemia or hyperkalaemia)
How do NSAIDs affect seizure activity?
Can worsen seizure threshold
What class of drugs can interact with NSAIDs and increase risk of seizures?
Fluoroquinolone antibiotics (e.g. ciprofloxacin)
Whart are 2 key side effects of fluoroquinolones (e.g. ciprofloxacin)?
1) lower seizure threshold
2) risk of tendon rupture
Typical drug dose for oral codeine?
30-60mg every 4 hours as required
What 3 doses does co-codamol come in?
8/500mg
15/500mg
30/500mg
Before prescribing any strong opiate, consider ABC.
What is this?
A - start antiemetic
B - consider breakthrough pain
C- constipation, prescribe laxative
Typical drug dosing for (oral) morphine in acute pain?
Initially 10mg every 4 hours
What class of medication is duloxetine?
SNRI
What can be considered for people with localised neuropathic pain who wish to avoid oral treatments?
Capsaicin cream
Side effects of cyclizine?
Dry mouth
Hypotension
Drowsiness
(antihistamine with some anticholinergic properties)
Major contraindication of metoclopramide?
Parkinson’s (use domperidone instead)
What anti-emetic is typically chosen for toxic causes of N&V?
e.g. hypercalcaemia
Haloperidol
What are the 2 chosen anti-emetics for end of life?
1) haloperidol
2) levopromethazine
Contraindications of haloperidol and levomepromazine?
Parkinson’s
Most common side effect of ondansetron?
Constipation
What are the 4 main types of laxatives?
1) bulk forming e.g. ispaghula husk
2) stimulant e.g. senna
3) osmotic e.g. lactulose
4) softener e.g. docusate
What is the 1st line laxative in palliative care?
Senna
What can be used in reducing the discomfort associated with a painful mouth that may occur at the end of life?
Benzydamine hydrochloride spray/mouthwash
1st line anti-emetic for intracranial causes of nausea and vomiting?
Cyclizine
3 options for metastatic bone pain?
1) analgesia
2) bisphosphonates
3) radiotherapy
Pharmacological managment of confusion/agitation in palliative care but for patients NOT in the terminal phase?
Oral haloperidol (if the patient was in the terminal phase and agitated then SC midazolam would be indicated)
What can be used to manage bowel colic in palliative care?
Hyoscine butylbromide
Pharmacological management of hiccups in palliative care?
Chlorpromazine or haloperidol
What is the benzodiazepine of choice in terminal agitation/restlessness?
Midazolam
Why is diazepam not given as an end of life drug?
Irritant when given SC
What is 1st line in cancer related breathlessness when no reversible element?
Low dose immediate release PO morphine (i.e. oramorph)
Describe performance status 1-5
0 = normal
1 = symptomatic & ambulatory, cares for self
2 = ambulatory >50% of time
3 = ambulatory <50% of time
4 = bedridden
5 = dead
How does metoclopramide achieve the effect of increased gastric emptying?
Antagonist of muscarinic receptor inhibition –> i.e. increased ACh
Starting syringe driver dose of metoclopramide?
30mg
Side effects of haloperidol?
1) EPSEs
2) Anticholinergic effects
3) Hyperprolactinaemia
4) Antiadreneric e.g. prolonged QT interval
5) Risk of NMS
6) Sedation
Contraindications of haloperidol?
1) LBD
2) Parkinson’s disease
3) CNS depression
4) Congenital long QT syndrome
5) Recent acute MI
6) History of torsades de pointes
What can be used to treat bowel colic 2ary to mechanical obstruction?
Hyoscine butylbromide
