Medically reviewed by A Ras MD.
What is prilocaine used for?
Prilocaine is a prescription medicine that is used before dental care to numb the area.
Lidocaine 2.5% and Prilocaine 2.5% Cream, USP is an emulsion in which the oil phase is a eutectic mixture of lidocaine and prilocaine cream 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 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. Lidocaine and prilocaine cream contains no preservative, however it passes the USP antimicrobial effectiveness test due to the pH. The specific gravity of lidocaine and prilocaine cream is 1.00.
Mechanism of Action
Lidocaine and prilocaine cream applied to intact skin under occlusive dressing, provides dermal analgesia by the release of lidocaine and prilocaine from the cream into the epidermal and dermal layers of the skin and by the accumulation of lidocaine and prilocaine in the vicinity of dermal pain receptors and nerve endings. Lidocaine and prilocaine are amide-type local anesthetic agents. Both lidocaine and prilocaine stabilize neuronal membranes by inhibiting the ionic fluxes required for the initiation and conduction of impulses, thereby effecting local anesthetic action.
The onset, depth and duration of dermal analgesia on intact skin provided by lidocaine and prilocaine cream depend primarily on the duration of application. To provide sufficient analgesia for clinical procedures such as intravenous catheter placement and venipuncture, lidocaine and prilocaine cream should be applied under an occlusive dressing for at least 1 hour. To provide dermal analgesia for clinical procedures such as split skin graft harvesting, lidocaine and prilocaine cream should be applied under occlusive dressing for at least 2 hours. Satisfactory dermal analgesia is achieved 1 hour after application, reaches maximum at 2 to 3 hours, and persists for 1 to 2 hours after removal. Absorption from the genital mucosa is more rapid and onset time is shorter (5 to 10 minutes) than after application to intact skin. After a 5 to 10 minute application of lidocaine and prilocaine cream to female genital mucosa, the average duration of effective analgesia to an argon laser stimulus (which produced a sharp, pricking pain) was 15 to 20 minutes (individual variations in the range of 5 to 45 minutes).
Dermal application of lidocaine and prilocaine cream may cause a transient, local blanching followed by a transient, local redness or erythema.
Before taking prilocaine, tell your doctor:
- If you are allergic to prilocaine; 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.
This is not a list of all drugs or health problems that interact with prilocaine.
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 prilocaine 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 prilocaine?
- Tell all of your health care providers that you take prilocaine. This includes your doctors, nurses, pharmacists, and dentists.
- Do not eat while your mouth feels numb. You may bite your tongue.
- This medicine may affect certain lab tests. Be sure your doctor and lab workers know you use prilocaine.
- 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.
- If you are 65 or older, use prilocaine 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 prilocaine 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 prilocaine best taken?
Use prilocaine as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- It is given as a shot.
- Your doctor will give prilocaine.
What do I do if I miss a dose?
- This medicine is given on an as needed basis.
What are the side effects of prilocaine 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.
- Signs of too much acid in the blood (acidosis) like confusion; fast breathing; fast heartbeat; a heartbeat that does not feel normal; very bad stomach pain, upset stomach, or throwing up; feeling very sleepy; shortness of breath; or feeling very tired or weak.
- A burning, numbness, or tingling feeling that is not normal.
- Numbness or tingling in or around the mouth that lasts or gets worse.
- Dizziness or passing out.
- Feeling lightheaded, sleepy, confused, or having blurred eyesight.
- Slow heartbeat.
- Sweating a lot.
- Ringing in ears.
- Low mood (depression).
- Very nervous and excitable.
- Trouble breathing, slow breathing, or shallow breathing.
- Change in balance.
- Feeling hot or cold.
What are some other side effects of prilocaine?
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 you have any side effects that bother you or do not go away.
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 prilocaine?
- If you need to store prilocaine at home, talk with your doctor, nurse, or pharmacist about how to store it.
IGI LABORATORIES INC.CARTON LABEL
FOUGERA PHARMACEUTICALS, INC. CARTON LABEL
SRC: NLM .