Ametop

Percutaneous local anaesthetic to produce anaesthesia of the skin prior to venepuncture or venous cannulation.

Ametop is indicated in adults and infants aged over 1 month.

Posology

Adults (including the elderly): A maximum of 5 tubes (approximately 5g) can be applied at separate sites at a single time. Application of Ametop gel can be repeated after a minimum of 5 hours if necessary. The maximum cumulative dose in a 24-hour period should not exceed 7 tubes.

Paediatric population

Ametop is contraindicated in premature babies or in full term infants less than 1 month of age (see section 4.3).

Infants over 1 month and children under 5 years of age: A maximum of 1 tube (approximately 1 g) can be applied at separate sites at a single time. Application of Ametop gel can be repeated after a minimum of 5 hours if necessary. The maximum cumulative dose in a 24-hour period should not exceed 2 tubes.

Children over 5 years of age: A maximum of 5 tubes (approximately 5 g) can be applied at separate sites at a single time. Application of Ametop gel can be repeated after a minimum of 5 hours if necessary. The maximum cumulative dose in a 24-hour period should not exceed 7 tubes.

Method of administration

Cutaneous route.

Precautions to be taken before handling or administering the medicinal product

It may be advisable to use a finger cot or rubber glove during application and removal of Ametop gel. Always wash hands thoroughly after use (see section 6.6).

Apply the contents of the tube to the centre of the area to be anaesthetised and cover with an occlusive dressing. The contents expellable from 1 tube (approximately 1 gram) are sufficient to cover and anaesthetise an area of up to 30 sq.cm. (6x5cm). Smaller areas of anaesthetised skin may be adequate in infants and small children. Each tube is intended for use on a single occasion only.

Adequate anaesthesia can usually be achieved following a thirty minute application time for venepuncture, and a forty-five minute application time for venous cannulation, after which the gel should be removed with a gauze swab and the site prepared with an antiseptic wipe in the normal manner.

It is not necessary to apply Ametop gel for longer than 30-45 minutes and anaesthesia remains for 4-6 hours in most patients after a single application.

Use in premature babies or in full term infants less than 1 month of age, where the metabolic pathway for tetracaine may not be fully developed. For premature babies use of Ametop is not recommended before 1 month after the expected delivery date (44 weeks 'gestation').

Hypersensitivity to the active substance, to local anaesthetics of the ester type, or to any of the excipients listed in section 6.1.

Do not apply Ametop gel to broken skin, mucous membranes or to the eyes or ears.

Only apply to intact, normal skin.

Not to be taken internally.

Ametop gel, like other local anaesthetics may be ototoxic and should not be instilled into the middle ear or used for procedures which might involve penetration into the middle ear.

Repeated exposure to Ametop gel may increase the risk of sensitisation reactions to tetracaine.

Although the systemic availability of tetracaine by percutaneous absorption of Ametop gel is low, caution should be exercised in patients with epilepsy.

Ametop contains Sodium methyl-p-hydroxybenzoate (E219) and Sodium propyl-p-hydroxybenzoate (E217) which may cause allergic reactions (possibly delayed).

None known

Pregnancy

There are no adequate data from the use of tetracaine in pregnant women. There are no animal studies to indicate direct or indirect harmful effects with respect to reproductive toxicity (see section 5.3).

The rapid hydrolysis of tetracaine by plasma pseudocholinesterase means that it is unlikely to present a significant hazard to the foetus when used as indicated.

As a precautionary measure, it is preferable to avoid the use of Ametop during pregnancy.

Breast-feeding

It is not known whether tetracaine or its metabolites are secreted in breast milk. A risk to the new-borns/infants cannot be excluded. Therefore the product is not recommended for use on breast feeding mothers.

Fertility

There are no clinical data regarding the potential effect of Ametop gel on fertility.

Ametop gel has no or negligible influence on the ability to drive or use machines.

Tabulated list of adverse reactions

The following listing of adverse reactions is based on clinical trial experience and/or post-marketing use. The frequency of adverse reactions reported during post-marketing use cannot be determined as they are derived from spontaneous reports. Consequently, the frequency of these adverse events is qualified as "not known".

Undesirable effects are listed by MedDRA System Organ Classes.

Assessment of undesirable effects is based on the following frequency groupings:

Very common: ≥ 1/10

Common: ≥ 1/100 to <1/10

Uncommon: ≥ 1/1,000 to <1/100

Rare: ≥ 1/10,000 to <1/1,000

Very rare: <1/10,000

Not known: cannot be estimated from the available data

Slight erythema is frequently seen at the site of application and is due to the pharmacological action of tetracaine in dilating capillary vessels. This may help delineating the anaesthetised area.

Slight oedema or itching are less frequently seen at the site of application. This may be due to the local release of histamine and 5-HT.

More severe erythema, oedema and/or itching confined to the site of application have rarely been reported.

In very rare instances, blistering of the skin at the site of application may be apparent - in these cases, remove the gel immediately and treat the affected area symptomatically.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Overdosage with Ametop gel is unlikely to result from application to intact skin. If accidentally ingested systemic toxicity may occur, and signs will be similar to those observed after administration of other local anaesthetics. These signs have been described as: signs of inebriation, tingling, numbness of the tongue, tinnitus, nystagmus, nausea or vomiting, twitching and ultimately convulsions. Oxygen is recommended as the first line treatment for systemic toxicity.

Pharmacotherapeutic group: Anaesthetics, Local, ATC code: N01BA03

Mechanism of action

Tetracaine is a local anaesthetic and is believed to act by blocking nerve conduction mainly by inhibiting sodium ion flux across the axon membrane. Tetracaine achieves this by acting upon specific receptors that control gating mechanisms responsible for conductance changes in specialised proteinaceous sodium channels.

Blocking sodium ion flux prevents the setting up of an action potential in the nerve axon, thus preventing pain receptors signalling to the central nervous system.

Pharmacodynamic effects

Tetracaine additionally has vasodilatory effects, which commonly results in a localised erythema.

The ester type 'caine' anaesthetics are rapidly metabolised in blood mainly by plasma pseudocholinesterase. A 3.33μ M (1μ g/ml) concentration of tetracaine was fully metabolised in human plasma within 20 seconds.

In vivo data has demonstrated that Ametop gel is 15 ± 11% bioavailable when administered to intact normal skin, with a mean absorption and elimination half life of 1.23 ± 0.28 hours.

Peak plasma levels of p-(n-butylamino) benzoic acid (BABA), the major metabolite of tetracaine are between 3-6 hours post dose.

None stated.

In addition to the active ingredient, Ametop gel contains:

Sodium Hydroxide (E524)

Sodium methyl-p-hydroxybenzoate (E219)

Sodium propyl-p-hydroxybenzoate (E217)

Monobasic potassium phosphate

Xanthan gum (E415)

Sodium chloride

Purified water

In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.

The shelf- life should not exceed 24 months from the date of manufacture.

Within the recommended shelf-life of 2 years at 2-8° C, the product, following dispensing may be stored for up to 1 month at 25° C at point of use.

Store at 2 - 8° C. Do not freeze. Protect from heat.

1.5g, internally lacquered, aluminium collapsible tubes, designed to deliver

1.0g of Ametop gel on squeezing.

As tetracaine can cause contact sensitisation reactions, particularly with repeated contact, healthcare professionals are advised to wash their hands thoroughly after use, to avoid contamination of other parts of the body. It may be advisable to use a finger cot or rubber glove during application and removal of Ametop gel.

Any unused medicinal product or waste material should be disposed of in accordance with local requirements.