caffeine + codeine + doxylamine succinate + paracetamol: clinical use

Prescribing considerations

• Confirm inadequate relief from simpler analgesics and exclude duplicate paracetamol or opioid exposure.
• Assess sedation, respiratory vulnerability, hepatic or renal impairment, constipation, urinary retention and dependence risk.
• Avoid in known CYP2D6 ultra-rapid metabolisers.
• Consider the additive sedating and antimuscarinic burden, particularly in older or debilitated patients.

Contraindications and cautions

• Hypersensitivity to any active ingredient, other opioid analgesics or excipients.
• MAOI treatment or the product-specified period after stopping it.
• Acute asthma attack, respiratory depression, chronic obstructive pulmonary disease, acute alcoholism, head injury or raised intracranial pressure.
• Risk of paralytic ileus, following biliary tract surgery, and breastfeeding.
• Children under 12; patients under 18 after tonsillectomy or adenoidectomy for obstructive sleep apnoea; known CYP2D6 ultra-rapid metabolisers.

Monitoring

• Sedation, cognition, respiratory rate and opioid toxicity.
• Constipation, abdominal symptoms and urinary retention.
• Hepatic risk factors and duplicate paracetamol exposure.
• Escalating use, withdrawal symptoms, medication-overuse headache or reduced analgesic response.

Clinical pharmacology

Paracetamol has analgesic and antipyretic activity. Codeine is a weak centrally acting opioid whose analgesia largely depends on CYP2D6 conversion to morphine. Doxylamine is a sedating H1 antihistamine with antimuscarinic activity; caffeine is a mild stimulant.

Formulation and product differences

• The selected product is a yellow film-coated tablet with a scoreline intended only to aid swallowing, not create equal portions.
• It contains lactose monohydrate, quinoline yellow and sunset yellow; the colourants may cause allergic reactions.
• It is essentially sodium-free.