Management of
Nausea & Vomiting
Dr Iain Lawrie
Specialist Registrar
in Palliative Medicine
Gut Mucosa
D2 5-HT3 ACh
Vestibular Apparatus
H1, ACh
Cortical Structures
Chemoreceptor
Trigger Zone
D2 5-HT3 Ach
Vomiting Centre
H1 5-HT2 ACh
Vomit
Gut Mucosa
D2 5-HT3 ACh
Vestibular Apparatus
H1 ACh
GI obstruction, bowel colic,
tumour mass, constipation
Motion
Cortical Structures
Chemoreceptor
Trigger Zone
Emotions, sights,
smells, raised ICP
D2 5-HT3 ACh
Drugs, toxins, uraemia,
hypercalcaemia
Vomiting Centre
H1 5-HT2 ACh
Vomit
Gut Mucosa
D2 5-HT3 ACh
Vestibular Apparatus
H1 ACh
GI obstruction, bowel colic,
tumour mass, constipation
Motion
Cyclizine, Hyoscine HBr
Metoclopramide,
Levomepromazine
Granisetron
Cortical Structures
Chemoreceptor
Trigger Zone
Emotions, sights,
smells, raised ICP
D2 5-HT3 ACh
Dexamethasone
Drugs, toxins, uraemia,
hypercalcaemia
Haloperidol
Metoclopramide
Levomepromazine
Granisetron
Vomiting Centre
H1 5-HT2 ACh
Cyclizine, Levomepromazine, Hyoscine HBr
Vomit
Factors to consider
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Mechanism of action of anti-emetic drugs
Response to anti-emetics already given
Combinations of drugs should have different
actions
Levomepromazine has multiple receptor
affinities
Factors to consider
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Effects of anti-emetics on GI motility
(prokinetic / antikinetic)
Adjuvant use of anti-secretory drugs
Adjuvant use of corticosteroids
Adverse effects of drugs
Cost of drugs
Management
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Correct reversible causes
stop gastric irritant drugs
treat gastritis
• PPIs / antacids
treat cough
• antitussive
treat constipation
• laxatives
Management
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Raised ICP
- steroids / radiotherapy
Anxiety
Hypercalcaemia
- rehydration +/- bisphosphonates
Causes of drug-induced N&V
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Gastric irritation
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Gastric stasis
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CTZ stimulation
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5HT3-receptor
stimulation
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Antibiotics, iron,
NSAIDs
Antimuscarinics,
opioids, TCA
Antibiotics, cytotoxics,
digoxin
Antibiotics, cytotoxics,
SSRIs
What if it’s not working?
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Is it being absorbed?
Is the dose optimum?
Do you have the correct cause?
Most anti-emetics can be given SC
Doses usually the same PO, SC and IV
Prescribing an anti-emetic
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Choice depends on cause of N&V
Give regularly
Alternative to oral route if unable to absorb
- subcutaneous stat doses
- continuous subcutaneous infusion (driver)
- rectal route
Anti-emetics – dopamine antagonists
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Haloperidol (D2)
Metoclopramide (D2, 5-HT3, 5-HT4 agonist)
Prochlorperazine (D2)
Domperidone (D2)
Levomepromazine (D2, ACh, H1, 5-HT3)
Side effects
- EPSE
- sedation in higher doses
- reduce seizure threshold
Anti-emetics – histamine antagonists
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Cyclizine (H1, ACh)
Levomepromazine (D2, ACh, H1, 5-HT3)
Side effects
- drowsiness
- anticholinergic effects
- postural hypotension
Anti-emetics - anticholinergics
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Hyoscine butylbromide (ACh)
Hyoscine hydrobromide (ACh)
Cyclizine (ACh)
Levomepromazine (D2, ACh, H1, 5-HT3)
Side effects
- sedation
- anticholinergic effects
Anti-emetics - prokinetics
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Metoclopramide (D2, 5-HT3, 5-HT4 agonist)
Domperidone (D2)
Side effects:
- colic
- EPSE (not domperidone – doesn’t cross BBB)
Anti-emetics – serotonin antagonists
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Ondansetron, granisetron, tropisetron
Side effects
- constipation
Place in palliative care
- obstruction / stretch
- resistant N&V
Anti-emetics - steroids
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Dexamethasone
Reduce permeability of BBB & area postrema
to emetogenic substances
Reduce neuronal content of GABA in the
brain stem
Reduce leuenkephalin release
Reduce oedema around lesion or tumour
Gastric stasis & irritation
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Nausea made worse by eating
Large volume vomits
Early fullness & bloating
Belching & reflux
Hiccups
Epigastric fullness & tenderness
Gastric stasis & irritation
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1st line metoclopramide
Adjuncts
- antiflatulent
- PPI
- stop irritant drugs
Bowel obstruction without colic
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Variable nausea
Vomiting dependent on site of obstruction
Abdominal distension
Background aching pain
Constipation
Absent or ‘hyperactive’ bowel sounds
Bowel obstruction without colic
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1st line metoclopramide
2nd line cyclizine or haloperidol (substitute)
Adjuvants
- diamorphine
- octreotide
- docusate
- steroids
Bowel obstruction with colic
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Symptoms as before, but with colicky pains
1st line cyclizine OR haloperidol PLUS
buscopan
2nd line cyclizine AND haloperidol OR
levomepromazine
Adjuvants
- diamorphine, octreotide, docusate
Chemical induced N&V
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Significant nausea
Variable vomiting
Few other GI symptoms
Evidence of presence
i.e. new drug started, biochemistry results
1st line haloperidol / metoclopramide
2nd line ADD cyclizine OR substitute
levomepromazine
Raised intracranial pressure
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Known intracerebral tumour
Early morning headaches
Predominant nausea
Intermittent vomiting
Papilloedema
Neurological deficit
Seizures
Raised intracranial pressure
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1st line dexamethasone & cyclizine
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2nd line ADD haloperidol
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3rd line 5-HT3 antagonist (substitute)
Motion / movement related N&V
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Nausea & vomiting worse on movement
Can be associated with cranial nerve lesions
and base of skull metastases
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1st line cyclizine
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2nd line hyoscine hydrobromide
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Indeterminate N&V
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1st line haloperidol OR cyclizine
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2nd line haloperidol AND cyclizine
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3rd line levomepromazine (substitute)
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4th line consider metoclopramide,
dexamethasone, 5HT3 antagonist
Summary
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Try to determine the cause wherever possible
 1/ 3
of patients will need more than one antiemetic
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Eliminate reversible causes
Continue anti-emetic indefinitely if cause is
not self-limiting