Topical local anaesthetics for acute pain management
Local anaesthetics can be applied topically to the skin or a mucosal surface. The degree of skin penetration and effect depends on the dose, formulation and duration of skin contact. Topical administration is noninvasive and produces minimal adverse effects. It is useful for:
- wound debridement, including venous ulcer debridement (see Mechanical wound debridement and Conservative sharp wound debridement)
- dressing changes
- venous access in children, or an anxious or needle-phobic patient
- mucositis
- eye procedures
- endoscopic airway procedures.
Topical local anaesthetic formulations commonly contain lidocaine, prilocaine or tetracaine (amethocaine). The dose required depends on the surface area to be anaesthetised, but should never exceed the maximum recommended dose for age and weight. See Commonly used topical local anaesthetic formulations for commonly used topical local anaesthetic formulations.
|
Formulation |
Brand name |
Other comments |
|---|---|---|
|
lidocaine 2% oral liquid or gel |
Xylocaine Viscous, Mucosoothe |
used for oropharyngeal anaesthesia rinse the oral liquid or gel in the mouth or gargle for 30 seconds then spit out, or swallow for anaesthesia of the pharynx avoid food or drink for 1 hour after application |
|
lidocaine 0.5%, 1% or 2% solution for injection |
Xylocaine |
used for dressing changes remove as much of the wound dressing as possible, then soak the remaining dressing with lidocaine solution and leave for 10 minutes. Remove remaining dressing once area is anaesthetised do not exceed maximum recommended dose |
|
lidocaine 4% liposomal cream |
LMX4 |
used in children before venepuncture or intravenous cannulation 1 g of lidocaine 4% liposomal cream contains lidocaine 40 mg. A 1 g dose is achieved by squeezing a length of 5 cm from the 5 g tube or 3.5 cm from the 30 g tube do not clean skin surface with alcohol or acetone before application because the cream has to mix with skin surface oils to be absorbed after application, cover the area with an occlusive dressing anaesthesia lasts 1 to 2 hours after removal of the cream |
|
lidocaine 2.5% + prilocaine 2.5% cream or patch |
EMLA Numit |
used for venepuncture, intravenous cannulation or minor dermal procedures (eg leg ulcer debridement) 1 g of cream or one patch contains lidocaine 25 mg and prilocaine 25 mg a 1 g dose of cream is achieved by squeezing a circular blob of cream the size of a small coin ($2), or by squeezing a length of approximately 3.5 cm from the tube after application, cover the area with an occlusive dressing anaesthesia lasts 2 hours after removal of the cream or patch |
|
lidocaine 4% + tetracaine (amethocaine) 0.5% + adrenaline (epinephrine) 0.1% topical solution—also known as ALA |
Laceraine |
combination product available in some hospitals for topical application to superficial wounds and lacerations less than 7 cm ineffective on intact skin soak cotton wool balls in the solution then hold in place over the laceration with a dressing |
|
tetracaine (amethocaine) 4% gel |
Local AnGel |
used for venepuncture or intravenous cannulation do not apply to broken skin 1 g of AnGel contains tetracaine 40 mg. A 0.5 g dose of AnGel is achieved by squeezing a circular blob of gel the size of a small coin ($2) after application, cover the area with an occlusive dressing anaesthesia lasts 4 to 6 hours after removal of the gel |
|
tetracaine (amethocaine) 0.5% or 1% eye drops |
Minims Amethocaine |
use for short ophthalmic procedures only (eg corneal foreign body removal) anaesthesia lasts up to 20 minutes never prescribe for home use if other eye drops are to be used during the procedure, instil tetracaine drops first because they reduce the initial stinging of subsequent eye drops, and increase their intraocular permeability |
If lidocaine 2% oral liquid or gel is indicated for oropharyngeal anaesthesia, use:
lidocaine 2% oral liquid or gel, rinse in the mouth or gargle for 30 seconds then spit out, or swallow for anaesthesia of the pharynx, every 3 hours as needed. Avoid food or drink for 1 hour after application local anaesthesia lidocaine
child younger than 3 years: up to 0.2 mL/kg (maximum 1.25 mL). Do not exceed 4 doses in 24 hours. It may be necessary to apply the liquid or gel with a cotton swab
child 3 to 12 years: up to 0.2 mL/kg (maximum 5 mL). Do not exceed 4 doses in 24 hours
adult and child older than 12 years: up to 15 mL. Do not exceed 8 doses in 24 hours.
If lidocaine 4% liposomal cream is indicated (eg for venepuncture or intravenous cannulation), use:
lidocaine 4% liposomal cream, applied to skin that has not been cleaned with alcohol or acetone. Cover the area with an occlusive dressing after application. Anaesthesia lasts for 1 to 2 hours after the cream has been removed lidocaine
infant 1 to 3 months: up to 1 g left on the skin’s surface for no longer than 60 minutes
infant 3 to 12 months: up to 1 g left on the skin’s surface for no longer than 4 hours
adult and child older than 1 year: up to 2.5 g left on the skin’s surface for no longer than 5 hours.
If lidocaine 2.5% and prilocaine 2.5% cream is indicated (eg for venepuncture, intravenous cannulation, minor dermal procedures), use:
lidocaine+prilocaine 2.5%+2.5% cream applied to skin. Cover the area with an occlusive dressing after application. Anaesthesia lasts 2 hours after the cream has been removed local anaesthesia lidocaine + prilocaine
infant younger than 3 months: up to 1 g left on the skin’s surface for 1 hour
infant 3 to 12 months: up to 2 g left on the skin’s surface for 1 to 4 hours
child 1 to 6 years: up to 10 g left on the skin’s surface for 1 to 4 hours
child 6 to 12 years: up to 20 g left on the skin’s surface for 1 to 4 hours
adult and child older than 12 years: up to 60 g on intact skin, or 10 g on leg ulcers, left on the skin’s surface for 1 to 4 hours (30 minutes may be sufficient for leg ulcers).
If lidocaine 2.5% and prilocaine 2.5% patches are indicated (eg for venepuncture, intravenous cannulation, minor dermal procedures), use:
lidocaine+prilocaine 2.5%+2.5% patches applied 1 hour before the procedure. Anaesthesia lasts 2 hours after the patch has been removed lidocaine + prilocaine
infant younger than 3 months: 1 patch left on the skin’s surface for no longer than 1 hour
infant 3 to 12 months: up to 2 patches left on the skin’s surface for no longer than 4 hours
adult and child older than 12 months: up to 5 patches left on the skin’s surface for no longer than 4 hours.
If lidocaine 4% and tetracaine (amethocaine) 0.5% and adrenaline (epinephrine) 0.1% topical solution is indicated (eg for superficial wounds and lacerations less than 7 cm), in adults and children 1 year or older, use:
lidocaine + tetracaine (amethocaine) + adrenaline (epinephrine) 4%+0.5%+0.1% topical solution: 0.1 mL/kg or 1 mL per cm of laceration (whichever is the smaller volume), up to 5 mL. Soak cotton wool balls in the solution, place on the laceration and hold in place with a dressing. Leave for 20 to 30 minutes (maximum 60 minutes). Do not exceed 4 doses in 24 hours. local anaesthesia lidocaine + tetracaine (amethocaine) + adrenaline (epinephrine)lidocaine+tetracaine (amethocaine)+adrenaline (epinephrine) lidocaine+tetracaine (amethocaine)+adrenaline (epinephrine)
If tetracaine (amethocaine) 4% gel is indicated (eg for venepuncture, intravenous cannulation), in adults and children older than 1 month, use:
tetracaine (amethocaine) 4% gel 0.5 g, applied to intact skin for up to 1 hour. Cover the area with an occlusive dressing after application. Anaesthesia lasts 4 to 6 hours after the cream has been removed. local anaesthesia tetracaine tetracaine (amethocaine) tetracaine (amethocaine)
If tetracaine (amethocaine) 0.5% or 1% eye drops are indicated for short ophthalmic procedures, in adults and children older than 1 month, use:
tetracaine (amethocaine) 0.5% or 1% eye drops: 1 drop into the affected eye; repeat after 5 minutes if required. tetracaine tetracaine (amethocaine) tetracaine (amethocaine)