Topical anaesthetics
| Anaesthetic | Availability | Active ingredients | Delivery vehicle | Time to effect | Duration of effect | Dosing |
|---|---|---|---|---|---|---|
| Topical anaesthetics for use on intact skin | ||||||
| Eutectic Mixture of Local Anesthetics (EMLA) | 5 and 30 g tubes; widely available throughout the world | 2.5% prilocaine, 2.5% lidocaine | Oil in water emulsion | 60 min superficial dermal, 120 min deeper dermal, 5–10 min mucosal | 1–2 h after removal of cream (shorter duration in more vascular areas) | Maximum dose and duration of application: 0–3 months or <5 kg: 1 g per 10 cm2 BSA for 1 h 3–12 months and >5 kg: 2 g per 20 cm2 BSA for 4 h 1–6 years old and >10 kg: 10 g per 100 cm2 BSA for 4 h 7–12 years old and >20 kg: 20 g per 200 cm2 BSA for 4 h |
| LMX4, LMX5 | 5, 15 and 30 g tubes; LMX4 widely available throughout the world | 4% and 5% liposomal lidocaine | Liposomes | 30 min | 60 min after removal of cream | 1 g per 10 cm2 BSA. Do not apply >1 g in <1 years old. Do not leave on for longer than 1 h in <3 months, >4 h in 3–12 months, >5 h in 12 months and older. Not recommended for <1 months old |
| Ametop | 1–1.5 g tube; UK, Canada, Australia, New Zealand | 4% tetracaine | Gel | 30–45 min | 4–6 h after removal | 1 tube can cover 30 cm2 BSA. Maximum 1 tube 1 months–5 years old, 2 tubes children >5 years old, 7 tubes in adults; not recommended in <1 months old |
| Synera or Rapydan | Patch; as Synera in US, Canada, Rapydan in parts of Europe | 70 mg lidocaine, 70 mg tetracaine | Patch with oxygen-activated heating element | 30 min | At least 100 min after patch removal | Approved for 3 years old and older |
| Topicaine | 10, 30, and 113 g tubes; US only | 4% or 5% lidocaine | Gel | 20 min to 1 h | 1 h after removal | Apply 1/8 inch thick layer. May use in ≥2 years old |
| Vapocoolant | Spray | Ethyl chloride | Cooling refrigerant spray | Instant | 60 s | Age 3 years or older |
| Pliaglis | Cream that hardens into flexible film; US, Canada, Europe, Argentina | 7% lidocaine, 7% tetracaine | Thick cream which self occludes | 20–60 min depending on procedures | Median duration 11 h | Only approved for adults (18 years or older) |
| Topical anaesthetics for laceration repair | ||||||
| LET or LAT | Compounded by hospital pharmacy | Lidocaine 4%, epinephrine 0.1%, tetracaine 0.5% | Aqueous solution or methylcellulose gel | 20–30 min | 45–60 min | Apply 1–3 mL into an open wound |
| TAC | Compounded by hospital pharmacy | Tetracaine 0.5%, adrenaline or epinephrine 0.05%, cocaine 11.8% | Aqueous solution | 20–30 min | Similar to LET in comparison studies | Apply into an open wound; mucous membrane exposure must be avoided |
BSA, body surface area.