Medically reviewed by Drugs.com. Last updated on Jan 17, 2022.
Addiction, misuse, and abuse may lead to overdose and death. Assess risk before prescribing and regularly monitor for signs of these behaviors and conditions. Serious and potentially fatal respiratory depression may occur. Monitor for respiratory depression, particularly when initiating or increasing dosage. Prolonged use of oxymorphone injection during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. Concomitant use of benzodiazepines or other CNS depressants, including alcohol, and opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for patients with inadequate alternative treatment options. Limit dosages and durations to the minimum required and follow patients for signs and symptoms of respiratory depression and sedation .
The Numorphan brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.
Commonly used brand name(s)
In the U.S.
Chemical Class: Opioid
Uses for Numorphan
Oxymorphone injection is used to treat moderate to severe pain, including labor pain. It may also be given before surgery or with a general anesthetic (medicine that puts you to sleep), and may be used to relieve anxiety for patients with breathing problems from pulmonary edema caused by heart disease.
Oxymorphone belongs to the group of medicines called narcotic analgesics (pain medicines). It acts on the central nervous system (CNS) to relieve pain.
When oxymorphone is used for a long time, it may become habit-forming, causing mental or physical dependence. However, people who have continuing pain should not let the fear of dependence keep them from using narcotics to relieve their pain. Mental dependence (addiction) is not likely to occur when narcotics are used for this purpose. Physical dependence may lead to withdrawal side effects if treatment is stopped suddenly. However, severe withdrawal side effects can usually be prevented by gradually reducing the dose over a period of time before treatment is stopped completely.
This medicine is available only with your doctor's prescription.
Before using Numorphan
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of oxymorphone injection in the pediatric population. Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of oxymorphone injection in the elderly. However, elderly patients are more likely to have age-related liver, kidney, heart, or lung problems, which may require caution and an adjustment in the dose for patients receiving oxymorphone injection.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with 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, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Calcium Oxybate
- Chloral Hydrate
- Gabapentin Enacarbil
- Magnesium Oxybate
- Methylene Blue
- Morphine Sulfate Liposome
- Nitrous Oxide
- Opium Alkaloids
- Potassium Oxybate
- Ropeginterferon Alfa-2b-njft
- Sodium Oxybate
- St John's Wort
- Tolonium Chloride
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Addison's disease (adrenal gland problem) or
- Alcohol abuse, or history of or
- Brain tumor, history of or
- Breathing or lung problems (eg, COPD, cor pulmonale, hypercapnia, hypoxia, sleep apnea) or
- Depression, history of or
- Drug dependence, especially with narcotics, or history of or
- Enlarged prostate (BPH, prostatic hypertrophy) or
- Gallbladder disease or gallstones or
- Head injuries, history of or
- Heart disease or
- Hypothyroidism (an underactive thyroid) or
- Hypovolemia (low blood volume) or
- Kyphoscoliosis (curvature of the spine with breathing problems) or
- Obesity, severe or
- Problems with passing urine or
- Weakened physical condition—Use with caution. May increase risk for more serious side effects.
- Hypotension (low blood pressure) or
- Pancreatitis (inflammation of the pancreas) or
- Seizures, history of—Use with caution. May make these conditions worse.
- Kidney disease or
- Liver disease, mild—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
- Liver disease, moderate or severe or
- Lung or breathing problems (eg, asthma, respiratory depression), severe or
- Stomach or bowel blockage (eg, paralytic ileus)—Should not be used in patients with these conditions.
Proper use of Numorphan
A nurse or other trained health professional will give you this medicine in a hospital. This medicine may be given as a shot under the skin, into a muscle or a vein.
Your doctor will give you a few doses of this medicine until your condition improves, and then switch you to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.
Precautions while using Numorphan
It is very important that your doctor check your progress while you are receiving this medicine. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it.
Avoid using this medicine and an MAO inhibitor within 14 days of each other.
This medicine will add to the effects of alcohol and other CNS depressants (medicines that can make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicine, other prescription pain medicine or narcotics, medicine for seizures or barbiturates, muscle relaxants, or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the medicines listed above while you are using this medicine.
Symptoms of an overdose include extreme dizziness or weakness, slow heartbeat or breathing, seizures, trouble breathing, and cold, clammy skin. Call your doctor right away if you notice these symptoms.
This medicine may cause sleep-related breathing problems (eg, sleep apnea, sleep-related hypoxemia). Your doctor may decrease your dose if you have sleep apnea (stop breathing for short periods during sleep) while using this medicine.
This medicine may cause serious allergic reactions, including anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Tell your doctor right away if you have a rash, itching, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.
This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.
Dizziness, lightheadedness, or fainting may occur when you get up suddenly from a lying or sitting position. Getting up slowly may help lessen this problem. Also, lying down for a while may relieve the dizziness or lightheadedness.
This medicine may make you dizzy, drowsy, confused, or disoriented. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.
Using narcotics for a long time can cause severe constipation. To prevent this, your doctor may direct you to take laxatives, drink a lot of fluids, or increase the amount of fiber in your diet. Be sure to follow the directions carefully, because continuing constipation can lead to more serious problems.
If you have been using this medicine regularly for several weeks or longer, do not suddenly stop using it without checking with your doctor. Your doctor may want you to gradually reduce the amount you are using before stopping it completely. This may help prevent worsening of your condition and reduce the possibility of withdrawal symptoms, such as abdominal or stomach cramps, anxiety, fever, nausea, runny nose, sweating, tremors, or trouble with sleeping.
Check with your doctor right away if you have anxiety, restlessness, a fast heartbeat, fever, sweating, muscle spasms, twitching, nausea, vomiting, diarrhea, or see or hear things that are not there. These may be symptoms of a serious condition called serotonin syndrome. Your risk may be higher if you also take certain other medicines that affect serotonin levels in your body.
Using this medicine while you are pregnant may cause neonatal withdrawal syndrome in your newborn babies. Tell your doctor right away if your baby has an abnormal sleep pattern, diarrhea, a high-pitched cry, irritability, shakiness or tremors, weight loss, vomiting, or fails to gain weight.
Using too much of this medicine may cause infertility (unable to have children). Talk with your doctor before using this medicine if you plan to have children.
Do not take other medicines unless thy have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Numorphan side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
Incidence not known
- Blurred vision
- chest pain or discomfort
- constricted, pinpoint, or small pupils (black part of the eye)
- difficult or painful urination
- difficult or troubled breathing
- difficulty with sleeping
- double vision
- drowsiness or sleepiness
- fast, pounding, or irregular heartbeat or pulse
- frequent urge to urinate
- irregular, fast or slow, or shallow breathing
- noisy breathing
- pale or blue lips, fingernails, or skin
- slow or irregular heartbeat
- seeing double
- seeing, hearing, or feeling things that are not there
- tightness in the chest
- unusual tiredness or weakness
- very slow breathing
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
- Bigger, dilated, or enlarged pupils (black part of the eye)
- cold, clammy skin
- difficult or troubled breathing
- increased sensitivity of the eyes to light
- irregular, fast or slow, or shallow breathing
- no muscle tone or movement
- pale or blue lips, fingernails, or skin
- very slow heartbeat
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
- Abdominal or stomach cramps or pain
- bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
- cold sweats
- decrease in frequency of urination
- decrease in urine volume
- difficulty having a bowel movement (stool)
- difficulty in passing urine (dribbling)
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- dry mouth
- loss of appetite
- mood or other mental changes
- sleepiness or unusual drowsiness
- skin rash, hives, itching, or redness
- swelling or puffiness of the face
- unusual tiredness
- weight loss
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
More about Numorphan (oxymorphone)
- Side effects
- Drug interactions
- Dosage information
- During pregnancy or Breastfeeding
- Drug class: narcotic analgesics
Related treatment guides
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