Brand Name: Emla
Generic Name: Lidocaine/Prilocaine
Manufacturer: Astra Zeneca
How does Emla work?
Emla cream contains two active ingredients, lidocaine (previously known as lignocaine in the UK) and prilocaine. These are both medicines called local anaesthetics. They are used to numb areas that would otherwise feel pain.
Pain is caused by the stimulation of pain receptors at the ends of nerves. The stimulation causes sodium to enter the nerve ending, which causes an electrical signal to build up in the nerve. When this electrical signal is big enough, it passes along the nerve to the brain, where the signal is interpreted as pain.
Lidocaine and prilocaine work by temporarily blocking this pathway of pain signals along nerves. They do this by stopping the sodium entering the nerve ending at the site of the pain. This prevents an electrical signal building up and passing along the nerve fibres to the brain.
When Emla cream is applied to the skin, the lidocaine and prilocaine prevent pain signals passing from that area to the brain and so numb the skin. This means otherwise painful procedures can be performed without causing pain.
The cream can be used to temporarily numb the surface of the skin before procedures such as injections, taking blood samples and minor skin surgery. In adults, the cream is applied in a thick layer underneath a dressing up to five hours before the procedure, and left on for at least one hour (at least two hours for procedures on large areas, eg split skin grafting). Your doctor, pharmacist or nurse will either apply the cream, or show you how much to use and where to apply it. This will depend on the procedure that will be performed. The dressing is removed just before the medical procedure starts. You can get dressings to use with the cream from your pharmacist or doctor.
The amount of cream to be used for children and the length of time it is left on will depend on the child’s age and weight. You should follow the instructions given by your doctor or nurse.
Under the supervision of a medical professional, the cream may also be used to temporarily numb the genitals in adults before the removal of genital warts (no dressings required for this use). The cream is applied five to ten minutes before this procedure starts.
What is it used for?
In adults, term newborn infants and children under the age of 18 years, Emla can be used to temporarily numb the surface of the skin before potentially painful procedures such as injections, taking blood and minor skin surgery.
In adults only, Emla can be used to temporarily numb the genital skin before surgical treatment of localised lesions, such as the removal of genital warts. In adult men it can also be used to numb the genital skin before injections of local anaesthetics into this area. A doctor or nurse must supervise the use of Emla when used on the genitals.
• Carefully follow the instructions supplied with the cream, or given by your doctor, nurse or pharmacist. The cream should not be rubbed into the skin.
• Wash your hands after applying the cream, unless your hands are the area being treated.
• Take care to avoid contact of this cream with the eyes, as this could numb the eye and prevent its protective reflexes, resulting in irritation. If you accidentally get the cream in your eyes, rinse well with lukewarm water or saline solution and protect the eye until sensation returns.
Use with caution in
- • Babies under 12 months of age.
- • Lack of the enzyme glucose-6-phosphate dehydrogenase in the blood (G6PD deficiency).
- • Disorder of the red blood cells called methaemoglobinaemia.
- • Anaemia.
- • People taking medicines that can cause anaemia or methaemoglobinaemia.
- • People taking medicines to treat an irregular heart beat, for example amiodarone or mexiletine.
- • Atopic dermatitis (eczema).
Not to be used in
- • Babies born prematurely (before 37 weeks).
- • Babies under 12 months of age who are being treated with medicines that can cause a disorder of the red blood cells called methaemoglobinaemia, for example sulphonamide antibiotics such as sulfamethoxazole (see end of factsheet for more examples).
- • Allergy to other anaesthetics of the amide type, eg bupivacaine, ropivacaine.
- • You should NOT apply the cream to cuts, grazes or wounds, or areas where there is a skin rash or eczema. Do NOT apply the cream in or near the eyes, inside the nose, ears, mouth or anus (back passage), or to the genitals of children.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- • This medicine should be used with caution during pregnancy and only on the advice of a doctor. Seek medical advice from your doctor.
- • Lidocaine and prilocaine pass into breast milk, but in amounts that are probably too small to be harmful to a nursing infant. However, women who are breastfeeding should seek medical advice from a doctor before using this medicine. If you are breastfeeding you should not apply this cream to the skin on or near the breasts, to prevent the child accidentally ingesting it.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.
Common (affect between 1 in 10 and 1 in 100 people)
- • Paleness, redness or swelling of the skin at the application site.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- • Mild burning, tingling or itching sensation at the application site (this is a common side effect when the cream is applied to the genitals).
Rare (affect less than 1 in 1000 people)
- • Disorder of the red blood cells called methaemoglobinaemia in children. Symptoms include bluish-grey skin due to a lack of oxygen. If this happens to your child you must consult a doctor immediately.
- • Allergic reactions.
- • Small red dots on the skin where the cream was applied. This is more likely in children with atopic dermatitis or mollusca contagiosa.
The side effects listed above may not include all of the side effects reported by the medicine’s manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already using, including those bought without a prescription and herbal medicines, before you use this medicine. Similarly, check with your doctor or pharmacist before using any new medicines with this one, to ensure that the combination is safe.
There may be an increased chance of a blood disorder called methaemoglobinaemia if this medicine is used by people who are being treated with other medicines that can cause this side effect, for example those listed below:
- • acetanilid
- • aniline dyes
- • benzocaine
- • chloroquine
- • dapsone
- • metoclopramide
- • naphthalene
- • nitrates and nitrites
- • nitrofurantoin
- • nitroglycerin
- • nitroprusside
- • pamaquine
- • para-aminosalicylic acid
- • phenacetin
- • phenobarbital
- • phenytoin
- • primaquine
- • quinine
- • sulphonamide antibiotics, eg sulfamethoxazole.
This cream should not be used in babies under 12 months of age who are being treated with any of the medicines listed above.
There may be an increased risk of side effects if large amounts of this medicine are used by people already using other local anaesthetics, or structurally-related medicines, such as tocainide or mexiletine.
The manufacturer states that this medicine should be used with caution in people taking medicines to treat an irregular heart beat, for example amiodarone, because if sufficient quantities of Emla are absorbed into the body it may increase the risk of side effects on the heart.