Consumer medicine information

NUMIT 5% cream

Lidocaine (lignocaine); Prilocaine

BRAND INFORMATION

Brand name

Numit 5% Cream

Active ingredient

Lidocaine (lignocaine); Prilocaine

Schedule

S2

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using NUMIT 5% cream.

What is in this leaflet

This leaflet answers some common questions about NUMIT.

It does not contain all the available information. It does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor has weighed the risks of you or your child using NUMIT against the benefits they expect it will have for you.

If you have any concerns about this medicine, ask your doctor or pharmacist.

Keep this leaflet with your medicine. You may need to read it again.

What is NUMIT used for?

NUMIT is a mixture of two local anaesthetics, lidocaine (lignocaine) and prilocaine.

These local anaesthetics are combined with special agents which allow the products to pass through the skin. Once through the skin the numbing effect they produce allows minor surgical procedures to be performed with a complete or significant reduction in pain.

These procedures can include taking blood samples, vaccination, skin grafting, cleaning leg ulcers, inserting an intravenous catheter, minor superficial cosmetic procedures and procedures on genital skin.

Numit is available as a cream which is applied then covered with a dressing.

Follow all directions given to you by your doctor carefully. They may differ from the information contained in this leaflet.

Your doctor or pharmacist may prescribe this medicine for another use. Ask your doctor or pharmacist if you want more information.

NUMIT is not addictive.

Before you use NUMIT

When you must not use this product

Do not apply NUMIT cream to any open wounds except leg ulcers.

Do not use NUMIT if you are pregnant or breastfeeding unless your doctor says it is safe.

The ingredients in NUMIT have been used for many years and no ill effects have been shown if they are used while you are pregnant.

Only very small amounts of NUMIT get into the blood so even though so even though your baby can take in NUMIT from breast milk if you are breast feeding.

NUMIT should not be used in premature babies.

We do not have enough knowledge yet to be sure if it is safe in premature babies.

Do not use after the use by (expiry) date printed on the pack or the packaging is torn or shows signs of tampering.

If it has expired or is damaged, return it to your pharmacist for disposal.

Do not use it to treat any other complaints unless your doctor says it is safe.

Do not give this medicine to anyone else.

Before you start to use it

You must tell your doctor or pharmacist about any of these.

  1. allergies you or your child have to any
    - ingredients listed at the end of this leaflet
    - local anaesthetic, for example those used at the dentist
    - adhesives or sticking plasters.
    If you or your child have an allergic reaction, you may get a skin rash, hay fever or an asthma attack.
  2. any of these medical conditions
    - dermatitis
    - methaemoglobinaemia
    - glucose-6-phosphate dehydrogenase deficiency
    - mollusca contasgiosa
    It may not be safe for you or your child to use NUMIT if you have any of these conditions.

Taking other medicines

Tell your doctor of pharmacist if you are using any other medicines including

  • a sulphonamide antibiotic eg sulfatrimoxazole
  • medicines used to treat irregular heartbeat such as amiodarone
  • medicines that you buy at your pharmacy, supermarket or health food shop
  • other local anaesthetics.

These medicines may affect the way NUMIT works or may cause adverse effects.

Your doctor or pharmacist can tell you what to do if you are taking any of these medicines.

How to use NUMIT

Directions

NUMIT is available as a cream.

Instructions on how to use NUMIT are included in the carton. Please read them carefully. The instructions also give maximum doses for adults and children. Do not exceed the maximum doses.

On intact skin
The most important thing to do is be sure that you apply NUMIT at least one hour before you are due to have the procedure except for skin grafting where a two hour application time is required or for procedures on male genital skin where only fifteen minutes is required.

Leg ulcers
If you are using NUMIT on leg ulcers you only need to apply the cream 30 minutes before your ulcer is going to be cleaned.

NUMIT can be left on for several hours and still work.

If you forget to use it

Apply NUMIT as soon as you realise it if it is less than an hour until you are supposed to have the procedure. Tell your doctor exactly when you put NUMIT on and they will decide when the procedure can take place.

If you have trouble remembering when to use your medicines, ask your pharmacist for some hints.

If you take too much (overdose)

Telephone your doctor or Poisons Information Centre (13 11 26), or go to Accident and Emergency at your nearest hospital immediately if you think that you or anyone else may have used too much NUMIT even if there are no signs of discomfort or poisoning.

For most procedures, it is difficult to use too much NUMIT. Be careful not to use too much in procedures where larger amounts may be required, such as cosmetic hair removal (see Package Insert for maximum amounts). Using too much Numit may cause unwanted side effects. Some of these can be serious such as methaemoglobinaemia (a condition where the blood cannot take enough oxygen to your blood) or cardiovascular effects (effects on your heart and lungs). If you use too much NUMIT, you may notice the following:

  • nervousness
  • dizziness
  • difficulty breathing
  • numbness of the mouth
  • your skin turning blue (a symptom of methaemoglobinaemia)
  • blurred vision
  • shaky hands
  • a rash where NUMIT has not been applied.

While you are using NUMIT

Things you must not do

Remember to apply NUMIT on intact skin at least one hour before your procedure is due. For leg ulcers remember to apply NUMIT 30 minutes before your ulcer is due to be cleaned. Apply NUMIT two hours before split skin grafting and at least fifteen minutes before a procedure on male genital skin.

If you do not, your or your child's appointment may have to be delayed, or the procedure may hurt more than it would otherwise.

If you or your child are using NUMIT on leg ulcers, only use the tube once. Throw out any cream left in the tube after use.

Things to be careful of

Do not use NUMIT cream on leg ulcers for longer than 2 months without checking with your doctor or pharmacist.

Be sure to follow the instructions in the pack on how to apply NUMIT cream carefully.

Make sure the dressing covering cream is firmly fixed, especially on young children.

Be careful not to let NUMIT get into the eyes.

It may cause eye irritation. If NUMIT does get into your eyes, immediately rinse them with large amounts of water and contact your doctor or pharmacist for advice.

Side effects

Tell your doctor or pharmacist as soon as possible if you or your child do not feel well while using NUMIT.

NUMIT helps most people to undergo minor procedures without feeling pain, but it may have unwanted side effects in a few people. All medicines have side effects.

Sometimes they are serious, most of the time they are not.

You may need medical treatment if you or your child get some of the side effects.

Ask your doctor or pharmacist to answer any questions you may have.

Tell your doctor or pharmacist if you notice any of the following and they worry you:

  • any local reaction such as itching, swelling, paleness, redness or a burning sensation.

These are all mild side effects of NUMIT.

If any of the following happen, remove NUMIT and tell your doctor immediately or go to casualty at your nearest hospital.

  • a rash at a spot where NUMIT is not being used.
  • difficulty breathing
  • dizziness
  • shaky hands
  • blurred vision
  • areas of skin becoming blue

These are very serious side effects. If you or your child have them, you or your child may have had a serious reaction to NUMIT and urgent medical attention or hospitalisation may be required.

All of these side effects are very rare.

Tell your doctor or pharmacist if you notice anything else that is making you or your child feel unwell.

Some people may get other side effects.

After using NUMIT

Storage

Keep your cream in the pack until it is time to use it.

If you squeeze NUMIT out of the tube it will not keep well.

Keep NUMIT in a cool dry place where the temperature stays below 30°C. Do not let it freeze.

Do not store NUMIT or any other medicine in the bathroom or near a sink. Do not leave it on a window sill or in the car.

Heat and dampness can destroy some medicines.

Keep it where young children cannot reach it.

A locked cupboard one-and-a-half metres above the ground is a good place to store medicines.

Disposal

Ask your pharmacist what to do with any NUMIT you have left over if your doctor tells you to stop using it, or you find that it has expired.

Shelf life

Do not use NUMIT after the expiry date printed on the pack. If you use it after the expiry date has passed, it may not work as well.

Product description

NUMIT cream contains:

  • lidocaine (lignocaine)
  • prilocaine
  • carbomer 934P
  • castor oil - ethoxylated hydrogenated
  • water - purified

For further information

This is not all the information that is available for NUMIT.

If you have any questions or are not sure about anything, ask your doctor or pharmacist.

Manufacturer

Ego Pharmaceuticals Pty. Ltd.
21-31 Malcolm Road, Braeside 3195
Australia.

Australian Registration number:
AUST R 265292.

Date of approval of leaflet: 29/09/2015.

Published by MIMS March 2017

BRAND INFORMATION

Brand name

Numit 5% Cream

Active ingredient

Lidocaine (lignocaine); Prilocaine

Schedule

S2

 

1 Name of Medicine

Lidocaine (lignocaine) and prilocaine.
Lidocaine is the new medicine ingredient name for lignocaine and is mostly used in this product information.

2 Qualitative and Quantitative Composition

Numit contains lidocaine 2.5% w/w (25 mg/g) and prilocaine 2.5% w/w (25 mg/g).
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Numit is a soft, white cream for topical application.
Numit is non-sterile.

4 Clinical Particulars

4.1 Therapeutic Indications

Numit is indicated for topical anaesthesia of the skin prior to insertion of IV catheters, mechanical cleansing or debridement of leg ulcers, cleaning ulcers, blood sampling, vaccination; superficial surgical procedures, including split skin grafting, minor surgical cosmetic procedures. Topical anaesthesia of genital skin prior to superficial surgical procedures or infiltration anaesthesia.

4.2 Dose and Method of Administration

In order to avoid cross contamination, infection control procedures and principles should be strictly adhered to during application of Numit.
Pharmacokinetic data for application longer than 4 hours is not available in children. In adults, there is no benefit in application times longer than 5 hours, as the analgesic effectiveness of the cream dissipates over time.

Use in elderly.

No dosage adjustment is required when Numit is applied to intact skin in the elderly.
Use in premature infants with a gestational age of less than 37 weeks is not recommended (see Section 4.4 Special Warnings and Precautions for Use).
Unscrew tube cap and peel off security seal. When used on leg ulcers discard the tube with any remaining Numit after each occasion that a patient is treated.
A 1 g dose of Numit cream is achieved by squeezing Numit from the tube into a circular area with diameter of approximately 20 mm (the size of a 2 dollar coin) to a depth of approximately 4 mm. Keep the tube in close contact with the skin until the correct amount has been applied.
A 1 g dose of Numit cream can also be achieved by squeezing a length of Numit of approximately 3.5 cm from the tube.
See Table 1 for dosing instructions.

4.3 Contraindications

Hypersensitivity to prilocaine, lidocaine or any local anaesthetics of the amide type.
Hypersensitivity to any of the excipients of Numit cream.
Glucose-6-phosphate dehydrogenase deficiency or congenital or idiopathic methaemoglobinaemia.

4.4 Special Warnings and Precautions for Use

Open wounds.

Numit should not be applied to open wounds other than leg ulcers, due to insufficient data on absorption from these sites.

Atopic dermatitis.

Care should be taken when applying Numit to skin areas with atopic dermatitis. A shorter application time (15-30 minutes) may be sufficient.

Eyes.

Numit should not be applied to or near to the eyes since it causes corneal irritation. Damage to the eye may also occur from undetected foreign bodies. Special care should be employed to reduce the risk of rubbing the eyes with Numit. It is therefore important that the patch or occlusive dressing should be secured against accidental dislocation, especially in young children.

Middle ear.

Lidocaine/prilocaine 5% cream is not recommended in any clinical situation in which its penetration into the middle ear is possible. In studies in rodents (guinea pigs) lidocaine/prilocaine 5% cream was found to have an ototoxic effect when instilled directly into the middle ear, however no abnormalities were observed when lidocaine/prilocaine 5% cream was applied to the animals' external auditory canal.
Lidocaine/prilocaine 5% cream caused minor structural damage to the tympanic membrane in rats when applied directly to the membrane. The relevance of these findings to the clinical situation is unknown.

Genital mucosa.

Lidocaine/prilocaine 5% cream is presently not recommended for use on genital mucosa. Available data suggest that the anaesthetic efficacy of Numit on genital mucosa may be variable.

Vaccination.

Lidocaine and prilocaine have bactericidal and antiviral properties in concentrations above 0.5-2%. A clinical trial with MMR vaccine administered subcutaneously demonstrated that lidocaine/prilocaine 5% cream does not adversely affect antibody response.
There are no data on effects of Numit on other live viral vaccines administered subcutaneously. When lidocaine/prilocaine 5% cream is used prior to intradermal BCG vaccination, the results of vaccination should be monitored.

Use in the elderly.

No data available.

Paediatric use.

Until further clinical data are available, lidocaine/prilocaine 5% cream should not be used in infants between 0 and 12 months of age receiving treatment with methaemoglobin inducing agents such as sulphonamides (also see Section 4.9 Overdose) or in preterm infants with a gestational age less than 37 weeks.
Studies have been unable to demonstrate the efficacy of lidocaine/prilocaine 5% cream for heel lancing in neonates.
Lidocaine/prilocaine 5% cream should not be applied to the genital mucosa of children owing to insufficient data on absorption. However, when used in neonates for circumcision (genital skin), a dose of 1.0 g lidocaine/prilocaine 5% cream on the prepuce has proven to be safe.
In children/ neonates younger than 3 months of age, a transient increase in methaemoglobin is commonly observed up to 12 hours after an application of lidocaine/prilocaine 5% cream.
Caution is required in those at risk of methaemoglobinaemia. Repeated applications of lidocaine/prilocaine 5% cream in neonates and infants have not been studied and should be avoided.
Use in premature infants with a gestational age of less than 37 weeks is not recommended.

Effects on laboratory tests.

No data available.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Antiarrhythmic drugs class III.

Patients treated with antiarrhythmic drugs class III (e.g. amiodarone) should be kept under close surveillance and ECG monitoring considered, since cardiac effects may be additive.
Specific interaction studies with lidocaine and antiarrhythmic drugs class III (e.g. amiodarone) have not been performed, but caution is advised.

Drugs reducing clearance of lidocaine.

Drugs that reduce the clearance of lidocaine (for example, cimetidine or beta-blockers) may cause potentially toxic plasma concentrations when lidocaine (e.g. Numit) is given in repeated high doses over a long time period. Such interactions should therefore be of no clinical importance following short-term treatment with lidocaine (e.g. Numit) at recommended doses.

Methaemoglobinaemia inducing agents.

Numit may accentuate the formation of methaemoglobin in patients treated with other drugs known to induce methaemoglobinaemia (e.g. sulphonamides).

Other local anaesthetic agents.

With large doses of Numit, the risk of additional systemic toxicity should be considered in patients receiving other local anaesthetics or agents structurally related to local anaesthetics, e.g. mexiletine.

Drugs reducing clearance of lidocaine.

Drugs that reduce the clearance of lidocaine (for example cimetidine or beta-blockers) may cause potentially toxic plasma concentrations when lidocaine (e.g. Numit) is given in repeated doses over a long time period. Such interactions should therefore be of no clinical importance following short-term treatment with lidocaine (e.g. Numit) at recommended doses.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

No data available.
(Category A)
Category A: Drugs which have been taken by a large number of pregnant women and women of child bearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the foetus having been observed.
No information is available on the excretion of lidocaine, prilocaine or their metabolites into breast milk following the administration of Numit.
Following parenteral administration, lidocaine is excreted into breast milk. Because of low maternal systemic absorption following application of recommended doses of Numit, the amount of lidocaine and prilocaine that may be ingested by the breastfed infant would be extremely small.

4.7 Effects on Ability to Drive and Use Machines

The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.

4.8 Adverse Effects (Undesirable Effects)

Intact skin.

Common events (≥ 1% and < 10%).

Skin.

Transient local reactions at the application site such as, paleness, erythema (redness) and oedema.
Uncommon events (≥ 0.1% and < 1%). Skin sensations (an initial mild burning sensation, itch or warmth at the application site).
Rare events (< 0.1%).

General.

In rare cases, local anaesthetic preparations have been associated with allergic reactions (in the most severe instances anaphylactic shock).
Rare cases of discrete local lesions at the application site, described a purpuric or petechial, have been reported, especially after longer application times in children with atopic dermatitis or mollusca contagiosa. Increased methaemoglobin level. Methaemoglobinaemia and/or cyanosis. Corneal irritation after accidental eye exposure.

Leg ulcer.

Common events (≥ 1% and < 10%).

Skin.

Transient local reactions at the application site such as, paleness, erythema (redness) and oedema.
Skin sensations (an initial mild burning sensation, itch or warmth at the application site).
Uncommon events (≥ 0.1% and < 1%).

Skin.

Skin irritation (at the application site).
Rare events (< 0.1%).

General.

In rare cases, local anaesthetic preparations have been associated with allergic reactions (in most severe instances anaphylactic shock).

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration 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 at www.tga.gov.au/reporting-problems.

4.9 Overdose

Rare cases of methaemoglobinaemia have been reported.
Prilocaine in high doses may cause an increase in the methaemoglobin level particularly in conjunction with methaemoglobinaemia inducing agents (e.g. sulphonamides). Clinically significant methaemoglobinaemia should be treated with a slow intravenous injection of methylene blue.
In the unlikely event of systemic toxicity following epidermal application of Numit, the signs and symptoms anticipated would be similar in nature to those observed following other routes of administration of local anaesthetics. Owing to slow absorption into the circulation from intact skin, a patient with signs of toxicity should be observed for several hours after treatment.
Systemic toxicity to amide type local anaesthetics is initially manifested as CNS excitation and may result in a slow onset of nervousness, dizziness, blurred vision and tremors followed by drowsiness, convulsions, unconsciousness and possibly respiratory arrest.
Toxic cardiovascular reactions to local anaesthetics are usually depressant in nature, may occur rapidly and with little warning and can lead to peripheral vasodilation, hypotension, myocardial depression, bradycardia and possible cardiac arrest. Severe neurological symptoms (convulsions, CNS depression) must be treated symptomatically by respiratory support and administration of anticonvulsive drugs.
For information on the management of overdose, contact the Poisons Information Centre on 131126 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Lidocaine and prilocaine are both amide type local anaesthetic agents. Both agents stabilise the neuronal membrane preventing the initiation and conduction of nerve impulses thereby effecting local anaesthetic action.
Numit provides dermal anaesthesia. The depth and quality of anaesthesia depends upon the application time and the applied dose.
Local anaesthesia with Numit is achieved after 60 minutes application. Numit cream should be applied under an occlusive, impermeable dressing. Following the application of Numit cream for 1-2 hours, the duration of anaesthesia is at least 2 hours after removal of the occlusive dressing.
Reliable anaesthesia for the cleansing of leg ulcers is achieved after an application time of 30 minutes in most patients. An application time of 60 minutes may improve the anaesthesia. The cleansing procedure should start within 10 minutes of removal of the cream. There is no clinical data regarding cleaning started after 10 minutes of cream removal.
A reduced number of cleansing sessions are required to achieve a clean ulcer when Numit is used compared to a placebo.
No negative effects on ulcer healing or bacterial flora have been observed.
Numit may cause transient local peripheral vasoconstriction or vasodilation, observed as transient paleness or redness, at the treated area.

Clinical trials.

In clinical trials with lidocaine/prilocaine 5% cream, venepuncture or venous catheterisation was pain free in 50-59% patients, slightly painful in 35-40% and painful in 3-6%. Anaesthesia may be less for skin structures below the deep fascia.
In clinical trials in adults assessing pain associated with intramuscular influenza vaccination and intramuscular and subcutaneous injections of saline solution, lidocaine/prilocaine 5% cream significantly reduced injection pain relative to placebo.
In clinical trials in infants and children assessing pain associated with subcutaneous and intramuscular vaccination, lidocaine/prilocaine 5% cream significantly reduced injection pain behaviours and pain scores relative to placebo.
In clinical trials assessing the effects of lidocaine/prilocaine 5% cream on intramuscular and subcutaneous, live and nonlive vaccines, it was demonstrated that lidocaine/prilocaine 5% cream does not adversely affect antibody response. A clinical trial assessing the effect of lidocaine/prilocaine 5% cream application prior to intracutaneous BCG injection demonstrated that lidocaine/prilocaine 5% cream did not affect the immunisation response.

5.2 Pharmacokinetic Properties

Absorption.

Systemic absorption and anaesthetic efficacy of lidocaine and prilocaine is dependent upon the characteristics of the leg ulcer, the applied dose, total application area, application time, thickness of the skin (which varies between different areas of the body), other conditions such as skin diseases, and shaving.

Intact skin.

The extent of systemic absorption was approximately 10% following application to the face (10 g/100 cm2 for 2 hours). Maximum plasma levels (mean 0.16 and 0.06 microgram/mL of lidocaine and prilocaine respectively) were reached after approximately 2.5 hours.
After application to the thigh in adults (60 g cream/400 cm2 for 3 hours) the extent of absorption was approximately 5% of lidocaine and prilocaine. Maximum plasma concentrations (mean 0.12 and 0.07 microgram/mL) were reached approximately 2-6 hours after the application.
In adults, a thick layer of lidocaine/prilocaine 5% cream (corresponding to approximately 150 g) has been applied to intact skin areas of up to 1,300 cm2 for application times of up to 7 hours. The highest individual plasma levels observed to date were 1.1 microgram/mL lidocaine and 0.2 microgram/mL prilocaine. These levels were below those at which symptoms of toxicity would be expected to occur (5-10 microgram/mL either agent; also see Section 4.8 Adverse Effects (Undesirable Effects)).

Leg ulcers.

Following a single application for 30 minutes of 5 to 10 g of lidocaine/prilocaine 5% cream to leg ulcers, the maximum plasma levels of lidocaine (range 0.05-0.25 microgram/mL, one individual value of 0.84 microgram/mL) and of prilocaine (0.02-0.08 microgram/mL) were reached within 1-2.5 hours.
After an application time of 24 hours the maximum plasma levels of lidocaine (0.19-0.71 microgram/mL) and of prilocaine (0.06-0.28 microgram/mL) were usually reached within 2-4 hours.
Following repeated applications for 30-60 minutes of 2-10 g lidocaine/prilocaine 5% cream 3-7 times a week, for up to 15 doses, during a period of one month, there was no apparent accumulation in plasma of lidocaine and its metabolites monoglycinexylidide and 2,6-xylidine or of prilocaine and its metabolite orthotoluidine. The maximum observed plasma levels for lidocaine, monoglycinexylidide and 2,6-xylidine were 0.41, 0.03 and 0.01 microgram/mL respectively. The maximum observed plasma levels for prilocaine and orthotoluidine were 0.08 microgram/mL and 0.01 microgram/mL respectively.

Children.

Following the application of 1.0 g of lidocaine/prilocaine 5% cream in neonates below 3 months of age, to approximately 10 cm2 for one hour, the maximum plasma concentration of lidocaine and prilocaine were 0.135 microgram/mL and 0.107 microgram/mL respectively.
Following the application of 2.0 g of lidocaine/prilocaine 5% cream in infants between 3 and 12 months of age, to approximately 16 cm2 for four hours, the maximum plasma concentrations of lidocaine and prilocaine were 0.155 microgram/mL and 0.131 microgram/mL respectively.
Following the application of 10.0 g of lidocaine/prilocaine 5% cream in children between 2 and 3 years of age, to approximately 100 cm2 for two hours, the maximum plasma concentrations of lidocaine and prilocaine were 0.315 microgram/mL and 0.215 microgram/mL respectively.
Following the application of 10.0-16.0 g of lidocaine/prilocaine 5% cream in children between 6 and 8 years of age, to approximately 100-160 cm2 for two hours, the maximum plasma concentrations of lidocaine and prilocaine were 0.299 microgram/mL and 0.110 microgram/mL respectively.
Pharmacokinetic data for application longer than 4 hours is not available in children. In adults, there is no benefit in application times longer than 5 hours, as the analgesic effectiveness of the cream dissipates over time.

5.3 Preclinical Safety Data

Genotoxicity.

Genotoxicity tests with lidocaine are inconclusive. In genotoxicity studies, a metabolite of lidocaine, 2,6-xylidine, showed evidence of activity in some tests but not in other tests.

Carcinogenicity.

A metabolite of lidocaine, 2,6-xylidine has been shown to have carcinogenic potential (nasal and subcutaneous tumours) in preclinical toxicological studies evaluating chronic exposure. A metabolite of prilocaine, o-toluidine, has also shown evidence of mutagenic activity in some genotoxicity tests but not others. o-toluidine has also been shown to have carcinogenic potential (e.g. renal, bladder, spleen subcutaneous tumours) in preclinical toxicological studies.

6 Pharmaceutical Particulars

6.1 List of Excipients

Each gram of Numit cream contains ethoxylated hydrogenated castor oil, purified water, carbomer 934P and sodium hydroxide as excipients.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 30°C.

6.5 Nature and Contents of Container

5 g laminate tube*, 10 g laminate tube and 30 g laminate tube, packed into a carton.
*Not currently marketed in Australia.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Numit cream is a 1:1 oil/water emulsion of an eutectic mixture of lidocaine and prilocaine.
When lidocaine and prilocaine are mixed in equal amounts, the solid pure bases of lidocaine and prilocaine form an oil at temperatures above 16°C (i.e. a eutectic mixture). By avoiding the need for nonaqueous solvent, higher concentrations of local anaesthetic in the cream can be achieved and maintained during application.

Lidocaine.

Molecular formula: C14H22N2O. Molecular weight: 234.3.

Prilocaine.

Molecular formula: C13H20N2O. Molecular weight: 220.3.

Chemical structure.


CAS number.

137-58-6, 721-50-6.

7 Medicine Schedule (Poisons Standard)

S2.

Summary Table of Changes