allantoin + lidocaine hydrochloride: clinical use

Prescribing considerations

• Confirm that symptoms are consistent with haemorrhoids rather than another cause of anorectal pain or bleeding.
• Persistent pain or bleeding, particularly with altered bowel habit, abdominal distension or unintentional weight loss, requires medical assessment.
• Avoid ocular contact with the ointment and counsel about accidental ingestion.
• Neither selected formulation is recommended for children.

Contraindications and cautions

• Hypersensitivity to lidocaine, allantoin or any excipient.
• The ointment contains wool fat, which may cause local contact dermatitis.

Monitoring

• Routine laboratory monitoring is not specified.
• Review persistent, recurrent or worsening symptoms and suspected hypersensitivity.
• Assess unexplained rectal bleeding or systemic warning features rather than continuing symptomatic treatment.

Clinical pharmacology

Lidocaine produces reversible local anaesthesia by inhibiting nerve impulse conduction. Allantoin is included for a proposed healing-support effect; product-specific pharmacokinetic data are unavailable.

Formulation and product differences

• Ointment is for external application and contains white soft paraffin, wool fat and purified water.
• Suppositories are for rectal administration and contain colloidal anhydrous silica, a hard-fat base and purified water.
• Only the suppository product information lists occasional diarrhoea as an undesirable effect.