Reviewed on 1/14/2022

Brand Name: Nubain

Generic Name: Nalbuphine

Drug Class: Opioid Analgesics

What Is Nalbuphine and How Does It Work?

Nalbuphine is a prescription medication used to treat pain and as an anesthesia supplement.

  • Nalbuphine is available under the following different brand names: Nubain.

What Are Dosages of Nalbuphine?

Adult and pediatric dosage

Injectable solution

  • 10mg/mL
  • 20mg/mL


Adult dosage

  • Non-opioid-tolerant patients: 10-20 mg/70kg IV/IM/SC every 3-6 hours as needed; individual dose not to exceed 20 mg
  • Opioid-dependent patients: Administer ¼ dose and observe for withdrawal signs. 
  • Not to exceed 160 mg/day

Pediatric dosage

  • Children younger than 1 year of age: Safety and efficacy not established
  • Children older than 1 year of age: 0.1-0.2 mg/kg IV/IM/SC every 3-4 hours as needed; individual dose not to exceed 20 mg; not to exceed 160 mg/day

Anesthesia Supplement

Adult dosage

  • 0.3-3 mg/kg IV over 1-15 minutes, then 0.25-0.5 mg/kg as needed

Dosage Considerations – Should be Given as Follows: 

  • See “Dosages”.

What Are Side Effects Associated with Using Nalbuphine?

Common side effects of Nalbuphine include:

Serious side effects of Nalbuphine include:

  • hives
  • difficulty breathing
  • swelling in the face, lips, tongue, or throat
  • slow breathing with long pauses, 
  • blue colored lips, 
  • difficulty to wake up, 
  • shallow breathing, 
  • breathing that stops during sleep
  • lightheadedness
  • severe drowsiness, 
  • severe constipation
  • nausea, 
  • vomiting, 
  • loss of appetite, 
  • dizziness, 
  • worsening tiredness or weakness, 
  • agitation, 
  • hallucinations, 
  • fever
  • sweating, 
  • shivering, 
  • fast heart rate
  • muscle stiffness, 
  • twitching, and
  • loss of coordination

Rare side effects of Nalbuphine include:

  • none 
This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.


Medically speaking, the term "myalgia" refers to what type of pain? See Answer

What Other Drugs Interact with Nalbuphine?

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them.  Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first

  • Nalbuphine has severe interactions with the following drug:
    • alvimopan
  • Nalbuphine has serious interactions with at least 51 other drugs.
  • Nalbuphine has moderate interactions with at least 183 other drugs.
  • Nalbuphine has minor interactions with the following drugs:

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this drug, tell your doctor or pharmacist of all the drugs you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

What Are Warnings and Precautions for Nalbuphine?


Effects of drug abuse

  • None

Short-Term Effects

  • See “What Are Side Effects Associated with Using Nalbuphine?”

Long-Term Effects

  • See “What Are Side Effects Associated with Using Nalbuphine?”


  • Cases of serotonin syndrome, a potentially life-threatening condition, reported with concomitant use of serotonergic drugs; this may occur within the recommended dosage range; the onset of symptoms generally occurs within several hours to a few days of concomitant use, but may occur later than that; discontinue therapy immediately if serotonin syndrome is suspected
  • Therapy may cause severe hypotension including orthostatic hypotension and syncope in ambulatory patients; there is increased risk in patients whose ability to maintain blood pressure has already been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (e.g., phenothiazines or general anesthetics); monitor patients for signs of hypotension after initiating or titrating dosage; in patients with circulatory shock, therapy may cause vasodilation that can further reduce cardiac output and blood pressure; avoid therapy in patients with circulatory shock
  • In patients who may be susceptible to intracranial effects of CO2 retention (e.g., those with evidence of increased intracranial pressure or brain tumors), therapy may reduce respiratory drive, and resultant CO2 retention can further increase intracranial pressure; monitor such patients for signs of sedation and respiratory depression, particularly when initiating therapy; opioids may obscure the clinical course in a patient with a head injury; avoid the use in patients with impaired consciousness or coma
  • Contraindicated in patients with known or suspected gastrointestinal obstruction, including paralytic ileus; may cause spasm of the sphincter of Oddi; opioids may cause increases in serum amylase; monitor patients with biliary tract disease, including acute pancreatitis, for worsening symptoms
  • Therapy may increase the frequency of seizures in patients with seizure disorders and other clinical settings associated with seizures; monitor patients for worsened seizure control during therapy
  • Avoid the use of mixed agonist/antagonist (e.g., pentazocine, nalbuphine, and butorphanol) or partial agonist (e.g., buprenorphine) analgesics in patients who are receiving a full opioid agonist analgesic; mixed agonist/antagonist and partial agonist analgesics may reduce the analgesic effect and/or precipitate withdrawal symptoms; when discontinuing therapy is physically dependent patient, gradually taper dosage; do not abruptly discontinue therapy in these patients
  • Warn patients not to drive or operate dangerous machinery unless they are tolerant to the effects of the drug and know how they will react to the medication
  • While serious, life-threatening, or fatal respiratory depression can occur at any time during therapy, the risk is greatest during initiation of therapy or following dosage increase; monitor patients closely for respiratory depression, especially within the first 24 to 72 hours of initiating therapy with and following dosage increases; accidental ingestion of even one dose, especially by children, can result in respiratory depression and death due to overdose of opioid
  • Opioids can cause sleep-related breathing disorders including central sleep apnea (CSA) and sleep-related hypoxemia; opioid use increases the risk of CSA in a dose-dependent fashion; in patients who present with CSA, consider decreasing opioid dosage using best practices for opioid taper
  • Deaths have occurred in nursing infants exposed to high levels of opioids in breast milk because mothers were ultra-rapid metabolizers of opioid
  • Profound sedation, respiratory depression, coma, and death may result from concomitant administration with benzodiazepines or other CNS depressants (e.g., non-benzodiazepine sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol); because of these risks, reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate
  • Use in patients with acute or severe bronchial asthma in an unmonitored setting or absence of resuscitative equipment is contraindicated; patients with significant chronic obstructive pulmonary disease or cor pulmonale, and with substantially decreased respiratory reserve, hypoxia, hypercapnia, or pre-existing respiratory depression are at increased risk of the decreased respiratory drive including apnea, even at recommended dosages
  • Life-threatening respiratory depression is more likely to occur in elderly, cachectic, or debilitated patients because they may have altered pharmacokinetics or altered clearance compared to younger, healthier patients; monitor closely
  • Monoamine oxidase inhibitors (MAOIs) may potentiate effects of opioid, opioid’s active metabolite, including respiratory depression, coma, and confusion; therapy should not be administered within 14 days of initiating or stopping MAOIs
  • Cases of adrenal insufficiency reported with opioid use, more often following greater than one month of use; symptoms may include nausea, vomiting, anorexia, fatigue, weakness, dizziness, and low blood pressure; if adrenal insufficiency is diagnosed, treat with physiologic replacement doses of corticosteroids; wean the patient off of the opioid to allow adrenal function to recover and continue corticosteroid treatment until adrenal function recovers; other opioids may be tried as some cases reported use of a different opioid without recurrence of adrenal insufficiency
  • Use caution when selecting a dosage for an elderly patient, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and concomitant disease or other drug therapy; because elderly patients are more likely to have decreased renal function, care should be taken in dose selection and may be useful to monitor renal function
  • Respiratory impairment; nalbuphine poses less risk of respiratory sedation than pure opioid agonists
  • Myocardial infarction
  • Cautions in hepatic impairment
  • Patients undergoing biliary tract surgery

Pregnancy and Lactation

  • Prolonged use of opioid analgesics during pregnancy can cause neonatal opioid withdrawal syndrome; there is no available data in pregnant women to inform a drug-associated risk for major birth defects and miscarriage; published studies with morphine use during pregnancy have not reported a clear association with morphine and major birth defects
  • Prolonged use of opioid analgesics during pregnancy for medical or nonmedical purposes can result in physical dependence in the neonate and neonatal opioid withdrawal syndrome shortly after birth; the onset, duration, and severity of neonatal opioid withdrawal syndrome vary based on the specific opioid used, duration of use, timing and amount of last maternal use, and rate of elimination of the drug by newborn; observe newborns for symptoms of neonatal opioid withdrawal syndrome and manage accordingly
  • Severe fetal bradycardia reported when administered during labor; naloxone may reverse these effects; although there are no reports of fetal bradycardia earlier in pregnancy, it may occur; the drug should be used in pregnancy only if needed if the potential benefit outweighs the risk to the fetus and if appropriate measures such as fetal monitoring are taken to detect and manage the potential adverse effect on the fetus
  • Morphine is present in breast milk; published lactation studies report variable concentrations of morphine in breast milk with administration of immediate-release morphine to nursing mothers in the early postpartum period with a milk-to-plasma morphine AUC ratio of 2.5:1 measured in one lactation study; however, there is insufficient information to determine effects of morphine on breastfed infant and effects of morphine on milk production; no information is available on effects of the drug on breastfed infant or effects of the drug on milk production
  • The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for therapy and any potential adverse effects on the breastfed infant from therapy or underlying maternal condition
  • Monitor infants exposed to therapy through breast milk for excess sedation and respiratory depression; withdrawal symptoms can occur in breastfed infants when maternal administration of morphine is stopped, or when breastfeeding is stopped

Labor or delivery

  • Opioids cross the placenta and may produce respiratory depression and psycho-physiologic effects in neonates; an opioid antagonist, such as naloxone, must be available for reversal of opioid-induced respiratory depression in neonates; the drug is not recommended for use in women during and immediately before labor when the use of shorter-acting analgesics or other analgesic techniques are more appropriate; opioid analgesics can prolong labor through actions that temporarily reduce strength, duration, and frequency of uterine contractions; however, this effect is not consistent and may be offset by an increased rate of cervical dilatation, which tends to shorten labor; monitor neonates exposed to opioid analgesics during labor for signs of excess sedation and respiratory depression


  • Due to the effects of androgen deficiency, chronic use of opioids may cause reduced fertility in females and males of reproductive potential; it is not known whether effects on fertility are reversible
Medscape. Nalbuphine.

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