EMLA

Generic name: lidocaine and prilocaine topical
Drug class: Topical anesthetics

Medically reviewed by  A Ras MD.

What is EMLA?

EMLA is a prescription medicine that is used to numb an area of the skin before a procedure. It is used to lower pain from shots.

Description

EMLA Cream (lidocaine 2.5% and prilocaine 2.5%) is an emulsion in which the oil phase is a eutectic mixture of lidocaine and prilocaine in a ratio of 1:1 by weight. This eutectic mixture has a melting point below room temperature and therefore both local anesthetics exist as a liquid oil rather than as crystals. It is packaged in 5 gram and 30 gram tubes.

Lidocaine is chemically designated as acetamide, 2-(diethylamino)-N-(2,6-dimethylphenyl), has an octanol: water partition ratio of 43 at pH 7.4, and has the following structure:

Prilocaine is chemically designated as propanamide, N-(2-methylphenyl)-2-(propylamino), has an octanol: water partition ratio of 25 at pH 7.4, and has the following structure:

Each gram of EMLA (lidocaine and prilocaine) Cream contains lidocaine 25 mg, prilocaine 25 mg, polyoxyethylene fatty acid esters (as emulsifiers), carboxypolymethylene (as a thickening agent), sodium hydroxide to adjust to a pH approximating 9, and purified water to 1 gram. EMLA (lidocaine and prilocaine) Cream contains no preservative, however it passes the USP antimicrobial effectiveness test due to the pH. The specific gravity of EMLA (lidocaine and prilocaine) Cream is 1.00.

Before taking EMLA, tell your doctor:

• If you are allergic to EMLA; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have methemoglobinemia.
• If you are using EMLA in the ear and you have a ruptured ear drum. Do not use in the ear if you have a ruptured ear drum.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take EMLA with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take EMLA?

• Tell all of your health care providers that you take EMLA. This includes your doctors, nurses, pharmacists, and dentists.
• This medicine may cause harm if swallowed. If EMLA is swallowed, call a doctor or poison control center right away.
• A severe blood problem called methemoglobinemia has happened with drugs like this one. The risk may be raised in people who have glucose-6-phosphate dehydrogenase (G6PD) deficiency, heart problems, or lung problems. The risk may also be raised while taking certain other drugs and in infants younger than 6 months of age. Tell your doctor if you have ever had methemoglobinemia.
• Do not put on open wounds, cuts, or irritated skin.
• Use care when putting on a large part of the skin or where there are open wounds. Talk with the doctor.
• Do not use EMLA for longer than you were told by your doctor.
• Do not scratch or rub the skin while it is numb. Do not let it get very hot or very cold.
• If you are 65 or older, use EMLA with care. You could have more side effects.
• Use with care in children. Talk with the doctor.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using EMLA while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is EMLA best taken?

Use EMLA as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Do not take EMLA by mouth. Use on your skin only. Keep out of your mouth, nose, and eyes (may burn).
• If you get EMLA in any of these areas, rinse well with water.
• Clean affected part before use. Make sure to dry well.
• Use a rubber glove to put on.
• Put a thick layer on the area to be treated. Do not rub in.
• You may need to cover the treated area with a bandage or dressing. Talk with the doctor.

What do I do if I miss a dose?

• Call your doctor to find out what to do.

What are the side effects of EMLA that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of methemoglobinemia like a blue or gray color of the lips, nails, or skin; a heartbeat that does not feel normal; seizures; very bad dizziness or passing out; very bad headache; feeling very sleepy; feeling tired or weak; or shortness of breath. This effect is rare but may be deadly if it happens.
• Very bad irritation where EMLA is used.
• Slow heartbeat.
• Dizziness or passing out.
• Feeling lightheaded, sleepy, confused, or having blurred eyesight.
• Change in balance.
• Restlessness.
• Anxiety.
• Change in speech.
• Shakiness.
• Twitching.
• Ringing in ears.
• Low mood (depression).
• Trouble breathing, slow breathing, or shallow breathing.
• Seizures.
• Numbness or tingling in the mouth.
• Change in taste.
• Feeling nervous and excitable.
• Change in how you feel hot or cold.
• Throwing up.

What are some other side effects of EMLA?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Irritation where EMLA is used.
• Redness.
• Pale skin.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out EMLA?

• Store at room temperature. Do not freeze.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

SRC: NLM .