meperidine

n.
A synthetic narcotic compound, C₁₅H₂₁NO₂, used in its hydrochloride form as an analgesic and sedative.

[ME(THYL) + (PI)PERIDINE.]

Key Terms: Agonist, Endorphin, Narcotic analgesic, Opioid.

Definition

Meperidine, available as hydrochloride salt, is a narcotic analgesic, a classification term used to describe medications capable of producing a reversible depression of the central nervous system for pain control. Because of its potential for physical and psychological dependence, meperidine is a carefully controlled substance. It is commonly referred to by one of its brand names, Demerol.

Purpose

There are several possible indications for the administration of meperidine. It is commonly used for the relief of moderate to severe pain, particularly in obstetrics. Meperidine is also widely used preoperatively, and as an adjunct to anesthesia during surgery. Meperidine is not recommended for long-term management of chronic pain, such as pain caused by cancer, because of its potential for psychological and physical dependence.

Description

Meperidine is a synthetic compound that acts as an agonist—meaning it attaches to opioid receptors in the central nervous system and stimulates physiologic activity normally stimulated by naturally occurring substances such as endorphins (short for endogenous morphine). Meperidine acts much like morphine, although constipation, suppression of the cough reflex, and smooth muscle spasm are all reduced with meperidine.

Meperidine is available in a banana-flavored syrup, in a tablet, and in a liquid form for injection. Oral meperidine tends to be less effective than the injectable form. When taking the syrup, patients should dilute it with approximately one half glass of water to reduce temporary anesthesia to the mouth and tongue.

Recommended Dosage

The recommended dosage of meperidine depends on the purpose for which it is prescribed, as well as the population in whom it is administered. For example, elderly patients, or patients with underlying medical problems that increase side effects or decrease drug metabolism, should generally be given reduced dosages. Meperidine can be taken orally, in tablet or syrup form, intravenously (directly into a vein), or by injection into the muscle (intramuscularly) or connective tissue (subcutaneously).

Generally, repeated doses administered to manage pain should be given by injection intramuscularly. The subcutaneous route is acceptable for occasional administration. When given intravenously, meperidine should be diluted and administered very slowly. When taken in conjunction with phenothiazine or other tranquilizers, the dose should be decreased by as much as a half. Specific dosages are as follows.

For Relief of Moderate to Severe Pain

The recommended dosage for adults for pain relief is 50–150 mg every three to four hours by oral or intramuscular route. When given intravenously through a patient-controlled analgesia (PCA) device, an initial dose of 10 mg should be administered. The PCA should be programmed to administer between 1–5 mg every 6–10 minutes. If meperidine is given continuously through an intravenous line, the dose should be adjusted based on patient response to a range of 15–35 mg an hour. Children should be given 1–1.8 mg per kg (2.2 pounds) intramuscularly or subcutaneously.

For Preoperative Medication

Adults may be given 50–100 mg of meperidine intramuscularly, or subcutaneously 30–90 minutes prior to surgery. Children's dosages should be reduced to 1–2 mg per kg through the same routes.

For obstetric pain control. The recommended dosage for control of regular (not sporadic) pain in this setting is 50–100 mg every 1–3 hours intramuscularly or subcutaneously.

Precautions

Other patients who should avoid meperidine use include those with previous hypersensitivity to narcotics, or those with underlying respiratory problems. Meperidine, even in recommended therapeutic doses, can decrease the respiratory drive. Conditions such as asthma or chronic obstructive pulmonary disease may increase the likelihood of respiratory difficulty. Meperidine can also impair judgment, and should not be used in individuals engaging in activities that require alertness, such as driving.

Because its effects on a fetus are unknown, meperidine is not recommended in pre-labor stage pregnant women. Even in labor, when it may be indicated for pain control, meperidine may cause respiratory depression of the mother and her baby, particularly premature babies. Meperidine is excreted in breast milk, and, if needed, should be administered several hours before breastfeeding to minimize ingestion by the infant.

Side Effects

The most common adverse effects of meperidine are lightheadedness, dizziness, sedation, nausea and/or vomiting, and sweating. Less common, but more severe, side effects include respiratory depression and abnormally low blood pressure.

Interactions

Individuals who are taking, or who have recently taken, drugs called monoamine oxidase (MAO) inhibitors (a class of antidepressants), should not be given meperidine. Reactions have been reported in this population that are characterized by a variety of signs and symptoms including respiratory distress, coma, abnormally low or abnormally high blood pressure, hyperexcitability, and even death. If administration of a narcotic is required, it should be given in small, gradually increasing test doses under careful supervision.

Adverse effects such as respiratory depression and decreased blood pressure are more common when meperidine is administered in conjunction with other narcotic analgesics, anesthetics, phenothiazines, sedatives, or any other type of drug that suppresses the central nervous system. Alcohol should also be avoided.

—Tamara Brown, R.N.

Brand names: Demerol®Meperitab™

Chemical formula:

Drug Forms:
• Meperidine Hydrochloride Oral tablet (below)
• Meperidine Hydrochloride Solution for injection
• Meperidine Hydrochloride Oral solution

Español:
• Clorhidrato de Meperidina, Tableta oral
• Clorhidrato de meperidina, Solución para inyección
• Clorhidrato de meperidina, Solución oral

Meperidine Hydrochloride Oral tablet

What is this medicine?

MEPERIDINE is a pain reliever. It is used to treat moderate to severe pain.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
• brain tumor
• drug abuse or addiction
• head injury
• heart disease
• kidney disease
• liver disease
• lung disease or breathing difficulties, including asthma
• seizures
• use within 14 days of a MAOI like Carbex, Eldepryl, Marplan, Nardil, and Parnate
• an unusual or allergic reaction to meperidine or other opiate drugs, other medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding

How should I use this medicine?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take your medicine more often than directed. Do not suddenly stop taking your medicine because you may develop a severe reaction. Your body becomes used to the medicine. This does NOT mean you are addicted. Addiction is a behavior related to getting and using a drug for a non-medical reason. If you have pain, you have a medical reason to take pain medicine. Your doctor will tell you how much medicine to take. If your doctor wants you to stop the medicine, the dose will be slowly lowered over time to avoid any side effects.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for selected conditions, precautions do apply.

Patients over 65 years old may have a stronger reaction and need a smaller dose.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
• MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate
• procarbazine
• ritonavir

This medicine may also interact with the following medications:
• acyclovir
• alcohol or medicines that contain alcohol
• antihistamines
• barbiturates like phenobarbital
• cimetidine
• furazolidone
• general anesthetics
• linezolid
• medicines for depression, anxiety, or psychotic disturbances
• medicines for pain
• medicines for sleep
• muscle relaxants
• naltrexone
• phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine
• phenytoin
• valacyclovir

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medicine?

Tell your doctor or health care professional if your pain does not go away, if it gets worse, or if you have new or a different type of pain. You may develop tolerance to the medicine. Tolerance means that you will need a higher dose of the medicine for pain relief. Tolerance is normal and is expected if you take the medicine for a long time.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.

This medicine may cause dry eyes and blurred vision. If you wear contact lenses you may feel some discomfort. Lubricating drops may help. See your eye doctor if the problem does not go away or is severe.

The medicine will cause constipation. Try to have a bowel movement at least every 2 to 3 days. If you do not have a bowel movement for 3 days, call your doctor or health care professional.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
• allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
• changes in vision
• confusion
• difficulty breathing, wheezing
• fainting spells
• hallucinations
• irregular heartbeat, palpitations
• seizures

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
• dizziness
• drowsiness
• nausea
• sweating

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medicine?

Keep out of the reach of children. This medicine can be abused. Keep your medicine in a safe place to protect it from theft. Do not share this medicine with anyone. Selling or giving away this medicine is dangerous and against the law.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Keep container tightly closed. Throw away any unused medicine after the expiration date.

Last updated: 7/1/2002

Important Disclaimer: The drug information provided here is for educational purposes only. It is intended to supplement, not substitute for, the diagnosis, treatment and advice of a medical professional. This drug information does not cover all possible uses, precautions, side effects and interactions. It should not be construed to indicate that this or any drug is safe for you. Consult your medical professional for guidance before using any prescription or over the counter drugs.

A centrally acting analgesic with spasmolytic properties equal to those of atropine. Has little hypnotic effect and relieves pain without reducing consciousness, muscular activity, coordination or responsiveness of the special senses. An addictive drug for humans. Called also pethidine.