Nausea Flashcards
Nausea definition
The conscious recognition that the vomiting centre has been stimulated
Vomiting definition
The forcible ejection of stomach contents through the mouth
Vertigo definition
Spinning feeling can accompany and predict the vomiting (similar aetiology(causes))
Nausea and vomiting dietary causes (3)
- Overeating
- food poisoning
- excess alcohol
Nausea and vomiting Infection causes (2)
- Viral infections
- bacterial infections
Nausea and vomiting disease causes (8)
- peptic ulcer disease
- gastroesophageal reflux disease
- gastric cancers
- obstructions
- renal failure
- diabetic ketoacidosis
- chronic obstructive pulmonary disease
- Myocardial Infarction (heart attack)
Nausea and vomiting CNS disease causes (3)
- migraines
- Meniere’s (inner ear disorder)
- motion sickness
Nausea and vomiting drug-induced causes (3)
- cytotoxic chemotherapy
- opiods
- anaesthetics
Other nausea and vomiting causes
pregnancy
What are the N&V receptors outside the brain (5)
- Chemoreceptor trigger zone (CTZ)
Contains:
- Serotonin 5HT3 receptors
- Dopamine D2 receptors
- Acetylcholine M receptors
- Histamine H1 receptors
What are the N&V receptors in the brain (5)
- Vomiting centre
Contains:
- Serotonin 5HT3 receptors
- Dopamine D2 receptors
- Acetylcholine M receptors
- Histamine H1 receptors
What are the N&V drug types (6)
- 5HT3 antagonists
- D2 antagonists
- D2/5HT3 antagonists
- Antimuscarinics
- Antihistamines
- Other
What are the N&V 5HT3 antagonist drug examples (3)
- Ondansetron
- Granisetron
- Dolasetron
What are the N&V D2 antagonist drug examples (5)
- Phenothiazines: prochlorperazine, levomepromazine
- Butyrophenones: Droperidol,
- Domperidone. Previously P, now POM
- Centrally acting D2 antagonists = extrapyramidal symptoms
- Phenothiazines and butyrophenones are also used in psychosis
What is the N&V D2/5HT3 antagonist drug examples
Metoclopramide - MHRA warning
What are the N&V antimuscarinics drug examples (2)
- Hyoscine HYDRObromide (scopolamine)
- Glycopyrrolate
What are the N&V antihistamine drug examples (3)
- Cinnarizine
- Cyclizine
- Promethazine (drowsy)
What are the N&V other drug examples (4)
- Prokinetic stimulants
- Benzodiazepines (for conscious causes)
- Cannabinoids
- Dexamethasone (with ondansetron as pre-med for chemo)
How is vestibular (ears and balance) N&V pharmacologically managed (5)
- Hyoscine hydrobromide - 30 mins before a journey
- Antihistamines - less effective but have fewer side effects
- Cinnarazine (antihistamine) - 2 hrs before journey
- Promethazine - VERY SEDATIVE, not often used now
- For Meniere’s Disease Hyoscine hydrobromide or antihistamines are used plus phenothiazines
How is pregnancy N&V pharmacologically managed (2)
- Avoid ALL drug treatment in first trimester
- In severe cases: 24-48 hours of promethazine or metoclopramide: REFER to SPECIALIST
How is cancer N&V pharmacologically managed (3)
- Prevent pre-exposure: phenothiazine, domperidone, dexamethasone
- Highly emetogenic: as on a 5HT3 antagonist (ondansetron)
- Second line: dexamethasone, phenothiazines, aprepitant, cannabinoids
How is Parkinson’s N&V pharmacologically managed (2)
- Domperidone (not centrally acting, but risk of QT prolongation)
- Cannabinoids
How is post-operative N&V pharmacologically managed (2)
- Often local guidelines
- 5HT antagonists and3 Cyclizine common
What is the relevance of the presence of abomination pain presentation in N&V (2)
- Various conditions would present with abdominal pain and it’s common to be associated with N&V
- severe pain would warrant referral
What is the relevance of the timing in N&V (3)
- Morning vomiting associated with alcohol intake and pregnancy
- If vomiting is immediately after food → Gastritis- → referral
- If vomiting is an hour after food → ulcer? → referral
What is the relevance of signs of infection presentation in N&V (2)
- Gastroenteritis – Diarrhoea, fever and abdominal discomfort
- Social history – if from food see if other people have it
What are the OTC treatments for travel sickness (3)
- Hyoscine bromide - 30 mins before travelling then every 6 hrs
- Cinnarazine - 2 hrs before driving then every 8 hrs as needed
- Promethazine - very drowsy, often abused - avoid
What is the OTC treatments for nausea associated with migraines (4)
- Promethazine - 18+
- placed on top gum under lip to dissolve
- Likely to cause drowsiness (aggravated with alcohol, opioids and antidepressants)
- Avoid use: Parkinson’s, epilepsy, glaucoma
What are the referral points for N&V (7)
- AB-PAIN
- Abdominal pain- moderate to severe
- Blood
- Potential pregnancy
- Age- Children under 1 y/o for >24 hours
- Identifiable cause? If not → refer
- Not responding to OTC treatment (limited OTC + hydration)
How does hydration affect N&V and how can this be sorted (6)
- need to make up about 2000 mL in food and drink
- Keep drinking and eating as normally as you can
- Use electrolyte solutions - Make up as instructed
- WHO recipe if can’t buy - 1 L water, ½ level teaspoon salt & 6 level teaspoons sugar (glucose)
- Bland things typically to start with: Crackers & toast
- If severely dehydrated refer – see signs of dehydration in diarrhoea later
