citric acid monohydrate: clinical use

Prescribing considerations

• Assess for an underlying cause when cough is persistent, worsening, productive or associated with systemic or respiratory red flags.
• Confirm the product-specific indication, concentration and licensed age range.
• Review excipients. Sucrose matters in diabetes and specified inherited carbohydrate disorders; maltitol and sorbitol are unsuitable in hereditary fructose intolerance and may cause gastrointestinal effects.

Contraindications and cautions

• Contraindications vary by product; several preparations specify hypersensitivity to the active substance or excipients.
• Avoid maltitol- or sorbitol-containing formulations in hereditary fructose intolerance.
• Avoid sucrose-containing formulations in inherited carbohydrate disorders specified by the relevant product information.
• Observe product-specific age restrictions.

Monitoring

• No routine laboratory monitoring is specified.
• Review symptom progression and screen for chest pain, haemoptysis, breathing difficulty or systemic illness.
• Monitor for hypersensitivity and gastrointestinal intolerance to maltitol or sorbitol.

Clinical pharmacology

The principal clinical action is demulcent. The syrup coats and lubricates irritated upper-airway mucosa. Citric acid is absorbed orally and metabolised through the citric acid cycle to carbon dioxide and water.

Formulation and product differences

• Adult and paediatric products differ in citric acid concentration and labelled age range and are not interchangeable.
• Standard formulations contain sucrose; sugar-free formulations use maltitol containing sorbitol.
• Excipients may include glycerol, sodium benzoate, flavouring and propylene glycol; consult product-specific information when clinically relevant.