NAUSEA AND VOMITING Flashcards
Causes
REMEMBER ‘VOMITING’
- vestibular
- opiates
- migraine
- infection
- toxicity with drugs
- Increased ICP
- neurodegenic
- gestation
Types of drugs for N+V
- Antihistamines
- Antimuscarinic
- 5HT3 Antagonist
List the antihistamines used for N&V
- Cinnarizine
- Cyclizine
- Promethazine hydrochloride
- Promethazine teoclate
Which causes of N&V are antihistamines used in?
- Vomiting during pregnancy = Promethazine
- Post-op = Cyclizine
- N&V in palliative care = Cyclizine
- Motion sickness
- Vertigo associated with meniere’s disease
What are the main side effects of
Antihistamines used for N&V?
Drowsiness and sedation
* Promethazine =most
* Cyclizine and Cinnarizine = less
List the antimuscarinic used for N&V
Hyoscine hydrobromide (NOT BUSCOPAN)
Note buscopan is Hyoscine
butylbromide
When is an antimuscarinic used in N&V?
- N+V associated with motion sickness
Which antimuscarinic is used for motion sickness?
Hyoscine hydrobromide
E.g. Kwells
Which antiemetics are
INEFFECTIVE in motion sickness?
- Dopamine antagonists
- 5HT3-antagonists
Antimuscarinic SEs
- Dry mouth
- Blurred vision
- Drowsiness and sedation (not as bad as antihistamines)
- Urinary retention
- Tachycardia
BT DUD
List the antimuscarinic used for 5HT3-antagonists
- Granisetron
- Odansetron
- Palonesteron
Which types of N&V
can the 5-HT3 antagonists be used in?
- N&V in patients receiving cytotoxic drugs
- Post-op N&V
Which 5-HT3 receptor antagonist can be found in a combination product with an NK1 antagonist, and which one?
Palonesteron can be found in combination with Netupitant
(NK1 antagonist)
What are the side effects of 5HT3 antagonists?
Generally well tolerated
- Gl upset
- Headache and flushing
- Most common is constipation
- QT
- SS
List the dopamine antagonists as an antiemetic in N&V
- Phenothiazines (Typical antipsychotics)
- Chlorpromazine (most sedating), Prochlorperzine, perphenazine, Trifluoperazine - Other antipsychotics e.g.
Levomepromazine, Haloperidol (unlicensed) - Metoclopramide
- Domperidone
What types of N&V are dopamine antagonists used for?
- Diffuse neoplastic disease
- Radiation sickness
- Emesis caused by drugs such as opioids, general anesthetics and cytotoxic drugs
Which phenothiazine is the most sedating?
Chlorpromazine
What are the side effects of
Phenothiazines?
MRS PG B
Which dopamine antagonist may be better in emesis associated with gastroduodenal, hepatic, and biliary disease? And why?
- Metoclopramide
- Act directly on GI tract so it is more superior then phenothiazines
What are the side effects of
metoclopramide?
- Parkinsonian symptoms
- Diarrhoea
- Drowsiness
What is a serious side effect of
Metoclopramide?
Neurological SE: dystonia
- particularly in children (esp young girls)
Dystonia
- Facial and skeletal muscle spasms would occur
- Occur shortly after starting treatment and subside within 24 hours of stopping it
- Procyclidine injected would stop these dystonic attacks
What are the guidances by MHRA on Metoclopramide to reduce the risk of neurological side effects?
- Use in 18+
- Short term (max 5 days)
- Usual dose 10mg TDS
These restrictions do not apply to unlicensed use e.g. palliative care
What are the cautions for use of
Metoclopramide?
- Children due to risk of serious neurological side effects
- Parkinson’s disease (due to parkinsonian symptoms which would worsen Parkinson’s)
- Asthma
What is the advantage of using domperidone over metoclopramide and phenothiazines?
- Domperidone does NOT BBB
- Metoclopramide (and phenothiazines do), which is why you can get sedation and neurological side-effects
- You DO NOT get sedation or dystonia with domperidone
What are the side-effects of
Domperidone?
- Dry mouth (Most common)
- QT prolongation
What is a serious side effect of
Domperidone?
- Serious cardiac side effects
- e.g. Arrhythmias, QT interval prolongation and sudden cardiac death
What are the guidances MHRA for domperidone in order to reduce the risk of cardiac side effects?
- It should only be used for relief of N&V (so not prophylaxis)
- Lowest effective dose and shortest possible duration ( Max 1 week)
Domperidone CI
- CI in cardiac disease
- QT interval prolongation drugs
- Drugs that are CYP inhibitors
Is domperidone effective for N&V in patient’s aged under
12 years old?
- No
- MHRA 2019 guidance suggests that there is no efficacy in children aged under
12 years old
What should patients and carers be advised on when taking domperidone?
How to recognise symptoms of arrhythmias e.g. palpitations and syncope
Which dopamine antagonist would you only offer to patient’s with Parkinson’s?
Domperidone
- Doesn’t cross BBB
List the NK1
antagonists used in
N&V
- Aprepitant
- Fosaprepitamt
- Netupitant
What are the use of
NK1 antagonists?
For prevention of N&V for moderate and highly emotogenic (e.g. Cisplatin)
cytotoxic drugs
What are the side effects of NK1 antagonists?
- Appetite decreased
- Asthenia
- Constipation
- Headache
- Hiccups
NK1 antagonists and hormonal contraceptives
- NK1 antagonists can reduce the effectiveness of hormonal contraceptives
- Barrier protection or non-hormonal alternatives should be used during treatment and 2 months after stopping
When is Nabilone used?
- When no other drug is effective
What are the side effects of Nabilone?
- Drowsiness
- Dizziness
- Dry mouth
Which type of N&V is dexamethasone used in?
N&V associated with cancer
It can be used on its own or with either:
- D2 antagonists
- 5HT3 antagonists
- NK1 antagonist
How do you treat nausea and vomiting during pregnancy?
- If the first trimester, then it’s usually mild and does not require drug therapy, offer advice such as oral hydration, rest and ginger etc.
- If vomiting is severe, then short-term therapy with pharmacological treatment
What antiemetics can be used in pregnancy?
- Chlorpromazine
- Cyclizine
- Metoclopramide
- Prochlorperazine
- Promethazine
- Ondansetron (avoid in first trimester)
What are the risk factors of postoperative nausea and vomiting (PONV)?
- Female gender
- Being a non-smoker
- History of PONV
- Use of opiod analgesia
- Type of surgery
Which anti-emetics are used as prophylaxis for PONV?
Prophylaxis only needed if there is a risk of PONV
- Dopamine antagonists
- 5HT3 antagonists
- Antihistamines
Combination of two or more is used if there is a HIGH RISK
How is N&V associated with cytotoxic drugs prevented?
- Prophylaxis depends on when symptoms occur (e.g. acute - within 24 hours, delayed - more than 24 hours, and anticipatory - occurring prior to subsequent doses)
- Prophylaxis also depends on risk factors e.g. women,
- Prophylaxis also depends on the level of emetogenic effect of cytotoxic drugs
List some of the cytotoxic drugs
according to the level of emesis: MILD
Mild:
- Florouracil
- Etoposide
- Methotrexate (Low dose)
- Vinca-alkaloids
- Abdominal radiotherapy
List some of the cytotoxic drugs
according to the level of emesis: MOD
Moderate:
- Taxanes
- Doxorubicin
- Low/intermediate dose of
Cyclophosphamide
List some of the cytotoxic drugs
according to the level of emesis: HIGH
High:
- Cisplatin
- Dacarbazine
- High doses of cyclophosphamide
How do you prevent acute symptoms of
N&V associated with cytotoxic drugs?
Low risk of emesis:
- pretreatment with Dexamethasone OR Lorazepam
High risk of emesis:
- Dexamethasone AND 5-HT3 antagonist and NK-1 antagonist (e.g. arepiprentant)
How do you prevent delayed symptoms of
N&V associated with cytotoxic drugs?
If delayed symptoms are associated with the moderate emetogenic drug:
- Dexamethasone + 5HT3
antagonist
If delayed symptoms are associated with the highly emetogenic drugs:
- Dexamethasone + aprepitant
How do you prevent **anticipatory
symptoms **of N&V associated with cytotoxic drugs?
- Good symptom control
- But lorazepam may be used for its sedative, amnesic, and anxiolytic effect (so it relieves anxiety which is one risk factor of N&V associated with cytotoxic drugs)
Which antiemtics can be used in ménière’s disease?
- Antihistamines
- Phenothiazines
- Betahistine
Which antiemetics is used buccally in N&V
associated with migraines?
Prochlorperazine 3mg
(buccastem)
