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Meperidine and promethazine

Generic Name: meperidine and promethazine (me-PER-i-deen and proe-METH-a-zeen)
Brand Name: Generic only. No brands available.

Meperidine and promethazine should not be used in children younger than 2 years old. Potentially fatal side effects (eg, difficult or slowed breathing, drowsiness leading to coma) may occur in this age group when taking a medicine that has promethazine in it.

Caution should be used when using meperidine and promethazine in children 2 years old and older. The lowest possible dose should be used in this age group, and it should not be used with other medicines that cause slowed breathing.


Meperidine and promethazine is used for:

Treating moderate to moderately severe pain.

Meperidine and promethazine is a narcotic analgesic and phenothiazine antihistamine combination. The narcotic analgesic works in the brain and nervous system to decrease pain. The phenothiazine antihistamine works by blocking the sites where histamine acts.

Do NOT use meperidine and promethazine if:

  • you are allergic to any ingredient in meperidine and promethazine
  • you have taken a monoamine oxidase inhibitor (MAOI) (eg, phenelzine) within the last 14 days
  • you have severe central nervous system depression or are in a coma

Contact your doctor or health care provider right away if any of these apply to you.

Before using meperidine and promethazine:

Some medical conditions may interact with meperidine and promethazine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have or have recently had any head injury, brain tumor or other growths, or increased pressure in the brain
  • if you have lung or breathing problems (eg, asthma, chronic obstructive pulmonary disease [COPD]), certain heart problems (eg, cor pulmonale, irregular heartbeat), low levels of oxygen in the blood (hypoxia), high levels of carbon dioxide in the blood (hypercapnia), stomach pain, kidney problems, liver problems, severe weakness, poor health, thyroid problems, adrenal gland problems (eg, Addison disease, pheochromocytoma), sickle cell anemia, drowsiness, curvature of the spine (scoliosis), low blood pressure, low blood volume, prostate problems, or urinary blockage or trouble urinating
  • if you have a history of seizures
  • if you drink alcohol or are going through withdrawal from alcohol or other substances

Some MEDICINES MAY INTERACT with meperidine and promethazine. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • MAOIs (eg, phenelzine) because the risk of serious side effects, including coma, difficulty breathing, low blood pressure, seizures, and irregular heartbeat, may be increased
  • Barbiturates (eg, phenobarbital), other narcotic pain medicines (eg, oxycodone), phenothiazines (eg, chlorpromazine), sleep medicines (eg, zolpidem), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of meperidine and promethazine's side effects

This may not be a complete list of all interactions that may occur. Ask your health care provider if meperidine and promethazine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use meperidine and promethazine:

Use meperidine and promethazine as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take meperidine and promethazine by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • If you miss a dose of meperidine and promethazine and you are using it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use meperidine and promethazine.

Important safety information:

  • Meperidine and promethazine may cause drowsiness or dizziness. These effects may be worse if you take it with alcohol or certain medicines. Use meperidine and promethazine with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Meperidine and promethazine may cause dizziness, light-headedness, or fainting; alcohol, hot weather, exercise, or fever can increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.
  • Check with your doctor before you drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using meperidine and promethazine; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
  • Meperidine and promethazine may cause constipation. Talk with your doctor or pharmacist about using a stool softener or laxative to prevent constipation. It is also important to maintain a diet adequate in fiber, drink plenty or water, and exercise to prevent constipation. If you become constipated while taking meperidine and promethazine, talk with your doctor or pharmacist.
  • Neuroleptic malignant syndrome (NMS) is a possibly fatal syndrome that can be caused by meperidine and promethazine. Symptoms may include fever; stiff muscles; confusion; abnormal thinking; fast or irregular heartbeat; and sweating. Contact your doctor at once if you have any of these symptoms.
  • Meperidine and promethazine may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to meperidine and promethazine. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
  • Tell your doctor or dentist that you take meperidine and promethazine before you receive any medical or dental care, emergency care, or surgery.
  • Use meperidine and promethazine with extreme caution in the ELDERLY; they may be more sensitive to its effects.
  • Meperidine and promethazine should not be used in CHILDREN younger than 2 years old. Serious, and sometimes fatal, side effects (difficult or slowed breathing, drowsiness leading to coma) have occurred when meperidine and promethazine has been used in children in this age group.
  • Meperidine and promethazine should be used with extreme caution in CHILDREN 2 years old or older. The lowest effective dose should be used in children 2 years old or older.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using meperidine and promethazine while you are pregnant. Meperidine and promethazine is found in breast milk. Do not breast-feed while using meperidine and promethazine.

When used for long periods of time or at high doses, meperidine and promethazine may not work as well and may require higher doses to obtain the same effect as when originally taken. This is known as TOLERANCE. Talk with your doctor if meperidine and promethazine stops working well. Do not take more than prescribed.

When used for long periods of time or at high doses, some people develop a need to continue taking meperidine and promethazine. This is known as DEPENDENCE or addiction.

If you suddenly stop taking meperidine and promethazine, you may experience WITHDRAWAL symptoms, including anxiety; appetite loss; backache; chills; diarrhea; enlarged pupils; fast heartbeat or breathing rate; increased tears; irritability; muscle or joint pain; nausea; restlessness; runny nose; severe or persistent dizziness; sleeplessness; stomach cramps; sweating; vomiting; weakness; and yawning.

Possible side effects of meperidine and promethazine:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Constipation; dizziness; drowsiness; dry mouth; light-headedness; nausea; sweating; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; confusion; fainting; fast, slow, or irregular heartbeat; fever, chills, or sore throat; hallucinations; mental or mood changes (eg, agitation, delirium, exaggerated sense of well-being, excitability, hysteria, nervousness); muscle problems with your tongue, face, mouth, or jaw (eg, tongue sticking out, puffing cheeks, mouth puckering, chewing); seizures; severe or persistent constipation; severe of persistent dizziness, drowsiness, or light-headedness; slow or shallow breathing or trouble breathing; tremor; uncontrolled muscle movements; unusual bruising or bleeding; vision changes; yellowing of skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of meperidine and promethazine:

Store meperidine and promethazine at room temperature, between 68 to 77 degrees F (20 to 25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep tightly closed. Keep meperidine and promethazine out of the reach of children and away from pets.

General information:

  • If you have any questions about meperidine and promethazine, please talk with your doctor, pharmacist, or other health care provider.
  • Meperidine and promethazine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take meperidine and promethazine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about meperidine and promethazine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to meperidine and promethazine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your health care provider for complete information about the risks and benefits of using meperidine and promethazine.

Review Date: November 3, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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