Lidocaine with prilocaine

How it works

Both agents reversibly block voltage-gated sodium channels in cutaneous nerve endings, preventing nerve impulse conduction and producing localised numbing once absorbed through the skin.

Prescribing in practice

• Prilocaine can cause methaemoglobinaemia, so avoid use in glucose-6-phosphate dehydrogenase deficiency and take particular care in young infants and with other methaemoglobinaemia-inducing drugs.
• Apply under an occlusive dressing for the recommended time before the procedure and avoid application to broken skin, wounds, eyes or mucous membranes unless a suitable formulation is specified.
• Avoid contact with the eyes as it may cause irritation and loss of protective reflexes.

Monitoring

Monitoring is clinical, observing for adequate anaesthesia, local reactions such as pallor or erythema, and — particularly in susceptible patients — signs of methaemoglobinaemia such as cyanosis.

Counselling the patient

• Apply the cream and cover with the dressing for the full time advised before your procedure.
• Temporary paleness, redness or mild swelling of the treated skin is normal.
• Keep the cream away from the eyes and do not apply to broken skin.

Evidence & guidelines

Topical lidocaine with prilocaine is a long-established surface anaesthetic with well-characterised pharmacology described in its SPC and standard prescribing references.