Some commonly used brand names are:

In the U.S.—

In Canada—

Another commonly used name for meperidine is pethidine.

• Analgesic
• Anesthesia adjunct
• Anesthesia adjunct, opioid analgesic

Narcotic analgesics (nar-KOT-ik an-al-JEE-zicks ) are given to relieve pain before and during surgery (including dental surgery) or during labor and delivery. These medicines may also be given before or together with an anesthetic (either a general anesthetic or a local anesthetic), even when the patient is not in pain, to help the anesthetic work better.

When a narcotic analgesic is used for surgery or obstetrics (labor and delivery), it will be given by or under the immediate supervision of a medical doctor or dentist, or by a specially trained nurse, in the doctor's office or in a hospital.

The following information applies only to these special uses of narcotic analgesics. If you are taking or receiving a narcotic analgesic to relieve pain after surgery, or for any other reason, ask your health care professional for additional information about the medicine and its use.

These medicines are available in the following dosage forms:

Parenteral
• Alfentanil
  • Injection (U.S. and Canada)
• Buprenorphine
  • Injection (U.S. and Canada)
• Butorphanol
  • Injection (U.S. and Canada)
• Fentanyl
  • Injection (U.S. and Canada)
• Meperidine
  • Injection (U.S. and Canada)
• Morphine
  • Injection (U.S. and Canada)
• Nalbuphine
  • Injection (U.S. and Canada)
• Remifentanil
  • Injection (U.S. and Canada)
• Sufentanil
  • Injection (U.S. and Canada)

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For narcotic analgesics, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to a narcotic analgesic. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Although studies on birth defects have not been done in pregnant women, these medicines have not been reported to cause birth defects. However, in animal studies, many narcotics have caused birth defects or other unwanted effects when they were given for a long time in amounts that were large enough to cause harmful effects in the mother.

Use of a narcotic during labor and delivery sometimes causes drowsiness or breathing problems in the newborn baby. If this happens, your health care professional can give the baby another medicine that will overcome these effects. Narcotics are usually not used during the delivery of a premature baby.

Breast-feeding—Some narcotics have been shown to pass into the breast milk. However, these medicines have not been reported to cause problems in nursing babies.

Children—Children younger than 2 years of age may be especially sensitive to the effects of narcotic analgesics. This may increase the chance of side effects.

Older adults—Elderly people are especially sensitive to the effects of narcotic analgesics. This may increase the chance of side effects.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, it may be necessary to change the dose, or other precautions may be necessary. It is very important that you tell the person in charge if you are taking:

• Any other medicine, prescription or nonprescription (over-the-counter [OTC]), or
• “Street” drugs, such as amphetamines (“uppers”), barbiturates (“downers”), cocaine (including “crack”), marijuana, phencyclidine (PCP, “angel dust”), and heroin or other narcotics—Serious side effects may occur if anyone gives you an anesthetic without knowing that you have taken another medicine

• Benzodiazepines or
• Central nervous system (CNS) depressants (medicine that causes drowsiness)—The CNS depressant and other effects of either these medicines or the narcotic analgesics may be increased

• Buprenorphine or similar medicines—The narcotic analgesics may not work if you are taking buprenorphine or other similar medicines

• Cimetidine or
• Erythromycin—Increased chance of side effects with some narcotic analgesics

• Naltrexone—The narcotic analgesics will not work if you are taking naltrexone

• Abdominal problems or
• Brain tumor or
• Head injury or
• Gallbladder disease or
• Heart disease or
• Kidney disease or
• Liver disease or
• Lung disease or
• Prostate disease or
• Thyroid disease or
• Urinary tract disease—Narcotic analgesics may make these conditions or the symptoms of these conditions worse

Dosing—

The dose of narcotic analgesic will be different for different patients. Your health care professional will decide on the right amount for you, depending on:

• Your age;
• Your general physical condition;
• The reason you are receiving the narcotic analgesic; and
• Other medicines you are taking or will receive before or after the narcotic analgesic is given.

For patients going home within a few hours after surgery:

• Narcotic analgesics and other medicines that may be given with them during surgery may cause some people to feel drowsy, tired, or weak for up to a few days after they have been given. Therefore, for at least 24 hours (or longer if necessary) after receiving this medicine, do not drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert.
• Unless otherwise directed by your medical doctor or dentist, do not drink alcoholic beverages or take other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness) for about 24 hours after you have received this medicine. To do so may add to the effects of the narcotic analgesic. Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; and muscle relaxants.

Along with its needed effects, a medicine may cause some unwanted effects. Before you leave the hospital or doctor's office, your health care professional will closely follow the effects of this medicine. However, some effects may continue, or may not be noticed until later.

Check with your medical doctor or dentist as soon as possible if any of the following side effects occur:

• More common
  • Dizziness, light-headedness, or feeling faint;  drowsiness;  nausea or vomiting;  unusual tiredness or weakness 
  
  

• Less common or rare
  • Blurred or double vision or other vision problems;  confusion;  constipation;  convulsions (seizures);  difficult or painful urination;  mental depression;  shortness of breath, trouble in breathing, tightness in the chest, or wheezing;  skin rash, hives, or itching;  unusual excitement 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although not specifically included in product labeling, fentanyl by injection is used in certain pediatric patients with the following medical conditions:

• Pain, during surgery, neonatal

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for these uses.