Topical ester local anaesthetic Pregnancy: No adequate data in pregnancy; as a precaution preferable to avoid use during pregnancy. Not recommended for use on breast-feeding mothers.

Tetracaine

Brand names: Ametop, Minims tetracaine

Tetracaine (amethocaine) is an ester-type local anaesthetic, used topically including as a gel to provide skin anaesthesia before cannulation or venepuncture and in ophthalmic preparations.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Up to 5 tubes (approximately 5 g) applied at separate sites at a single time

Route: Cutaneous (topical) - apply to intact skin and cover with an occlusive dressing; product: Ametop gel

Frequency: Application may be repeated after a minimum of 5 hours if necessary

Max: Maximum cumulative dose 7 tubes in a 24-hour period

Adults including the elderly. One tube (approximately 1 g) covers and anaesthetises an area up to 30 sq cm. Apply for 30 minutes before venepuncture, or 45 minutes before venous cannulation, then remove gel; anaesthesia persists for 4 to 6 hours after a single application. Each tube is single-use. Paediatric dosing (per SPC, not per-kg): contraindicated in premature babies and full-term infants under 1 month; infants over 1 month and children under 5 years - max 1 tube (about 1 g) per application, repeat after minimum 5 hours, max 2 tubes/24 h; children over 5 years - as per adult (max 5 tubes/application, max 7 tubes/24 h).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Premature babies, or full-term infants less than 1 month of age
Hypersensitivity to tetracaine, to ester-type local anaesthetics, or to any excipient
Do not apply to broken skin, mucous membranes, or the eyes or ears

Side effects

Application site erythema (common) - due to pharmacological capillary dilatation
Application site oedema (uncommon)
Application site pruritus (uncommon)
Application site vesicles / blistering (very rare) - remove gel immediately and treat symptomatically

Interactions

None known (SPC section 4.5)

Clinical monograph

How it works

It reversibly blocks voltage-gated sodium channels in nerve membranes, preventing the initiation and conduction of pain impulses.

Prescribing in practice

Systemic absorption can cause local anaesthetic toxicity, so it must not be applied to large areas, broken or inflamed skin, or mucous membranes beyond its licensed use, and total exposure should be limited.
Local erythema, oedema and pruritus at the application site are common and usually transient.
Hypersensitivity to ester-type local anaesthetics is a contraindication; cross-reactivity within the ester class can occur.

Monitoring

Observe the application site for local reactions and remain alert for systemic features of local anaesthetic toxicity if large amounts are absorbed.

Counselling the patient

Numbing gel applied to the skin before a needle to reduce the pain of cannulation.
Mild redness or itching where it is applied is common and settles.
Remove the dressing and gel as directed and do not apply to broken skin.

Evidence & guidelines

Topical tetracaine is well established for reducing pain of venepuncture and cannulation, with its use and precautions described in the SPC.

Reference: AAGBI; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

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