Drugs in palliative care Flashcards
What causes nausea and vomiting in palliative care
Chemo Constipation Hypercalcaemia Oral candidiasis GI obstruction Drugs Severe pain Infection Renal failure
How should anti-emetics be chosen?
Based on the likely mechanism of nausea
Consider the site of action especially when using combination of drugs
Describe how Cyclizine works and when it is good for nausea?
Antihistamine and anticholinergic, central action
Good for intracranial disorders
Describe how metoclopramide works and when it is good for nausea
Blocks central chemoreceptor trigger zone, peripheral prokinetic effects so good in gastroparesis, monitor for extrapyramidal side effects
Describe how domperidone works
Peripheral antidopaminergic so no dystonic effects
Describe how haloperidol works and when it is good for nausea
Dopamine antagonist, effective in drug or metabolically induced nausea, use lower doses IV/SC as twice as potent
Describe how ondansetron works and when it is good for nausea
Serotonin antagonist
Good for chemo/radiotherapy related nausea, may cause constipation
Describe how levomepromazine works and when it is good for nausea
Broad spectrum
Can sedate and be very effective if fear/anxiety are contributing to symptoms
List the 5 principles by which pain is managed
By the mouth By the clock By the ladder For the individual Attention to detail
Describe the WHO pain ladder
Step 1 - non opioid eg. paracetamol
Step 2 - opioid for mild to moderate pain eg. codeine
Step 3 - opioid for moderate to severe pain eg morphine, diamorphine, oxycodone
What other drugs must be prescribed with opioids
Laxative and antiemetic
Describe how you prescribe opioids
Start low and go slow - 5mg oral morphine every 4hrs plus PRN 5mg morphine
Convert to modified release - calculate dose every 12hrs by calculating 24hr oral dose and divide by 2
Use a PRN dose for breakthrough pain - 1/6th total daily dose as an immediate release preparation (oramorph or sevredol)
List the side effects of opioids
Drowsiness
Nausea and vomiting
Constipation
Dry mouth
Describe the signs of opioid toxicity
Sedation Respiratory depression Visual hallucination Myoclonic jerks Delirium
When should naloxone be used?
Life threatening respiratory depression
What happens if naloxone is given when it is not a life threatening situation
Pain crisis and potentially fatal acute withdrawal
Describe opioid use in those with renal failure
At risk of toxicity due to accumulation of renally excreted opioids and metabolites
Fentanyl, alfentanil and buprenorphine have predominately hepatic metabolism so may be used in renal failure
What drug can be used for rapid analgesia for pain during mobilising to toilet or being changed etc
Buccal fentanyl
What causes constipation
Opioids Hypercalcaemia Dehydration Drugs Intra-abdominal disease
How is constipation treated
Treat reversible causes
Good fluid intake
Ensure privacy and access to toilet
Medication options include:
- Stimulant (senna or bisacodyl) and softener (sodium docusate)
- Osmotic laxative (macrogol)
- Rectal treatments (Bisacodyl/glycerol suppositories)
What causes breathlessness in palliative care
Infection, effusion, anaemia, arrhythmia, the disease, thromboembolism. superior vena cava syndrome
How is breathlessness treated in palliative care?
Low dose/ breakthrough dose opioid
Benzodiazepine if associated anxiety (eg. lorazepam/midazolam)
List some causes of oral problems in palliative care
Poor oral hygiene
Radiation
Drugs - anticholinergics, chemotherapy and diuretics
Infection - candidiasis and anticholinergics
How is oral candidiasis treated?
Topical miconazole or oral fluconazole (check interactions with warfarin)
Oral nystatin may not work and may increase nausea
How is herpes simplex treated?
Oral gan/aciclovir
List the end of life anticipatory medications
Morphine for pain Haloperidol for agitation and N&V Midazolam for anxiety and agitation Levomepromazine for N&V Glycopyrronium for troublesome resp secretions
What must be done in terms of prescribing when someone is end of life/final days of life
Remove any unnecessary medications
Prescribe anticipatory medications
Start syringe driver if needed - remember to include regular doses when calculating requirements
What are syringe drivers
Allow a continuous SC infusion of drugs, avoid repeated cannulation and injection when the oral route is not feasible
