Indications
Licensed indications for different anti-emetic agents:
| Drug | N & V | Motion sickness | Vertigo | Chemotherapy N&V | Meniere’s dis. | Post-op N&V | Migraine |
|---|---|---|---|---|---|---|---|
| Betahistine | X | ||||||
| Cinnarizine | X | ||||||
| Cyclizine | X | X | X | X (Radiotherapy) | X | X | |
| Domperidone | X | ||||||
| Metoclopramide | X | X | X | ||||
| Ondansetron | X | X | |||||
| Prochlorperazine | X | X | X | X | |||
| Promethazine | X |
Cautions / interactions
The information in the tables should be used in conjunction with the BNF or the SPC (medicines.ie)
| Drug | Contra-indications | Cautions | Side Effects | Interactions |
|---|---|---|---|---|
| Betahistine | Phaeochromocytoma |
Hx of peptic ulcer Not recommended <18 yrs old |
Nausea Dyspepsia Headache |
Antihistamines Caution with MAOIs |
| Cinnarizine |
Children <5 yrs |
GI obstruction Parkinson’s |
Nausea Dyspepsia Somnolence ↑ weight Antimuscarinic S/Es |
Alcohol CNS depressants TCAs |
| Cyclizine |
Acute alcohol intoxication (↑ toxicity of alcohol) Not recommended in children <6yrs |
Severe heart failure Acute MI Prostatic hypertrophy Urinary retention Glaucoma GI obstruction Epilepsy Hypertension |
Nausea Dyspepsia Antimuscarinic S/Es Loss of appetite |
Additive effects with alcohol & other CNS depressants e.g hypnotics, tranquillisers, anaesthetics. NB: Reports of abuse of cyclizine for its euphoric or hallucinatory effects |
| Domperidone | Prolactinoma, cond. where ↑ gastric motility is harmful e.g. GI haemorrhage Impaired cardiac conduction Concomitant drugs that prolong QT interval Hepatic impairment Concomitant CYP3A4 inhibitors |
Not recommended if <12 yrs or >60yrs May prolong QT interval Use lowest dose for shortest duration |
Dry mouth GI disturbance Galactorrhoea |
Drugs that prolong QT e.g. erythromycin, citalopram, haloperidol & amiodarone Potent CYP3A4 inhibitors e.g. systemic azole antifungals & some macrolides erythromycin & clarithromycin |
| Metoclopramide | GI obstruction, perforation or haemorrhage Phaeochromocytoma Children <1yr Eepilepsy Parkinson’s Disease |
Elderly Those <20yrs Cardiac disorders Electrolyte imbalance Bradycardia Renal & hepatic impairment Methaemo-globinaemia |
Diarrhoea Somnolence Hypotension (post IV doses) Extrapyramidal S/Es (esp in <20 yrs or in high doses) Hyperpro-lactinaemia |
Ciclosporin Alcohol (enhanced sedation) CNS depressants SSRIs (risk serotonin syndrome) Levodopa or dopaminergic agonists |
| Ondansetron | Congenital long QT syndrome Concomitant use with apomorphine |
Risk of QT prolongation GI obstruction Adenotonsillar surgery (may mask occult bleeding) Electrolyte abnormalities CCF Correct hypokalaemia & hypomagnesaemia prior to administration |
Constipation Headache Flushing |
Phenytoin Carbamazepine & rifampicin alter effectiveness of ondansetron Erythromycin, domperidone, citalopram & other drugs that prolong QT interval SSRIs & SNRIs (risk of serotonin syndrome) Apomorphine C/I Tramadol |
| Prochlorperazine | Avoid in kids <10kg or 1 yr., Impaired liver function |
Hypothyroidism Elderly Cardiac failure Prostate hypertrophy Epileptic patient (lower seizure threshold) Parkinson’s CV disease or family Hx of QT prolongation |
S/Es occur at low frequency Extrapyramidal S/Es QT prolongation & cardiac arrhythmias (usually dose related) |
µ blockers (hypotensive effect) Antacids (absorption) Drugs that can prolong QT Abrupt cessation can lead to acute withdrawal symptoms incl. nausea, vomiting, sweating & insomnia Adrenaline mustn’t be used in patients overdosed with prochlorperazine |
| Promethazine | Kids <2yrs due to potential for fatal resp depression Avoid in pts taking MAOI up to 14 days previously Pts with blood dyscrasias CNS depression of any cause |
Asthma Bronchitis Bronchiectasis Bladder neck or pyloroduodenal obstruction Severe coronary artery disease Narrow angle glaucoma Epilepsy Hepatic & renal insufficiency Children with signs & symptoms of Reye’s Syndrome | Drowsiness Dizziness Restlessness Headaches Nightmares Tiredness Disorientation |
Action of anticholinergic agents, TCAs, Sedatives or hypnotics is enhanced Alcohol should be avoided Promethazine may interfere with urine pregnancy tests Promethazine may lower seizure threshold, may need to dose adjust AEDs Antihypertensives |