hyoscine hydrobromide: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
hyoscine hydrobromide: clinical details
Prescribing considerations
- Confirm the formulation and licensed indication; tablet and injectable products differ.
- Assess cumulative antimuscarinic burden and susceptibility to central toxicity, particularly in children and older people.
- Use caution with cardiovascular disease, seizure disorders, fever, renal or hepatic impairment, ulcerative colitis, gastro-oesophageal reflux and risk of urinary retention.
- Reduced sweating can impair temperature regulation in fever or hot environments.
- Intramuscular injection is contraindicated during anticoagulant treatment because of haematoma risk.
Contraindications and cautions
- Hypersensitivity to hyoscine hydrobromide or formulation excipients.
- Selected tablet: glaucoma, prostatic enlargement, paralytic ileus, pyloric stenosis and myasthenia gravis.
- Selected injection: angle-closure glaucoma, myasthenia gravis, tachycardia, acute porphyria, megacolon, gastrointestinal obstruction or mechanical stenosis, prostatic enlargement with urinary retention, onset of labour and paralytic ileus.
Monitoring
- Observe recipients of parenteral hyoscine for hypersensitivity or anaphylaxis.
- Monitor for urinary retention, bowel hypomotility, visual symptoms, tachyarrhythmia, confusion, hallucinations, excessive sedation and impaired temperature regulation.
- Arrange urgent ophthalmological assessment for a painful red eye with loss of vision.
- No routine plasma-concentration monitoring is described for the selected products.
Clinical pharmacology
A tertiary antimuscarinic that crosses the blood–brain barrier and inhibits muscarinic acetylcholine signalling centrally and peripherally. It suppresses vestibular input to the vomiting centre and reduces salivary, bronchial and sweat-gland secretion.
Formulation and product differences
- The selected tablet is a pharmacy product licensed for prevention of travel sickness and may be sucked, chewed or swallowed.
- The selected injection is prescription-only and licensed for nausea, vomiting, vertigo, labyrinthine disorders, motion sickness and reduction of bronchial or salivary secretions during general anaesthesia.
- The injectable product may be given subcutaneously or intramuscularly; intravenous administration is described for acute adult use by healthcare professionals.
hyoscine hydrobromide preparations and strengths
Tablet
Route: Oral
Strengths: 150 micrograms, 300 micrograms
Injection
Route: Parenteral
Strengths: 400 micrograms/mL, 600 micrograms/mL
hyoscine hydrobromide interactions
Check other medicines with a pharmacist or prescriber, particularly those with antimuscarinic or sedating effects.
Other antimuscarinics, including ipratropium, tiotropium and amantadine
May increase dry mouth, constipation, urinary retention, blurred vision and confusion.
Sedating antihistamines, antidepressants and antipsychotics
May intensify antimuscarinic effects, sleepiness or confusion.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.