Medical Editor: John P. Cunha, DO, FACOEP
Narcan (naloxone) is an opioid antagonist used for the complete or partial reversal of opioid overdose, including respiratory depression. Narcan is also used for diagnosis of suspected or known acute opioid overdose and also for blood pressure support in septic shock. Narcan is available in generic form. Common side effects of Narcan and narcotic drug withdrawal are:
- flushing,
- dizziness,
- tiredness,
- weakness,
- nervousness,
- restlessness,
- irritability,
- body aches,
- diarrhea,
- stomach pain,
- nausea,
- fever,
- chills,
- goosebumps,
- sneezing,
- shortness of breath, or
- runny nose.
Severe side effects of Narcan include:
- agitation,
- high or low blood pressure,
- cardiac arrhythmias,
- shortness of breath,
- pulmonary edema,
- abnormal brain function (encephalopathy),
- seizures,
- coma, and
- death.
Narcan is available as a sterile solution for intravenous, intramuscular, and subcutaneous administration in three strengths: 0.02, 0.4 and 1 mg of naloxone hydrochloride per mL in sterile solution; the 0.4 and 1 mg doses are also available in multidose vials. Use in neonates and other pediatric patients is based on weight (usually 0.01 mg per Kg) and may be adjusted; a pediatric consultant may help manages such patients. Opioid withdrawal syndrome may occur in some patients given large doses of Narcan. Studies on the use of this drug in pregnant and women who are breastfeeding have not been done. Tell your doctor if you are pregnant or breastfeeding.
Our Narcan Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
- chest pain, fast or irregular heartbeats;
- dry cough, wheezing, feeling short of breath;
- sweating, severe nausea or vomiting;
- severe headache, agitation, anxiety, confusion, ringing in your ears;
- seizure (convulsions);
- feeling like you might pass out; or
- slow heart rate, weak pulse, fainting, slow breathing (breathing may stop).
If you are being treated for narcotic drug addiction, the expected symptoms of withdrawal would include:
- feeling nervous, restless, or irritable;
- body aches;
- dizziness, weakness;
- diarrhea, stomach pain, mild nausea;
- fever, chills, goosebumps; or
- sneezing, runny nose.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Read the entire detailed patient monograph for Narcan (Naloxone Hydrochloride Injection)
SIDE EFFECTS
Postoperative
The following adverse events have been associated with the use of NARCAN (naloxone) in postoperative patients: hypotension, hypertension, ventricular tachycardia and fibrillation, dyspnea, pulmonary edema, and cardiac arrest. Death, coma, and encephalopathy have been reported as sequelae of these events. Excessive doses of NARCAN (naloxone) in postoperative patients may result in significant reversal of analgesia and may cause agitation (see PRECAUTIONS and DOSAGE AND ADMINISTRATION; Usage in Adults-Postoperative Opioid Depression) Opioid Depression
Abrupt reversal of opioid depression may result in nausea, vomiting, sweating, tachycardia, increased blood pressure, tremulousness, seizures, ventricular tachycardia and fibrillation, pulmonary edema, and cardiac arrest which may result in death (see PRECAUTIONS).
Opioid Dependence
Abrupt reversal of opioid effects in persons who are physically dependent on opioids may precipitate an acute withdrawal syndrome which may include, but is not limited to, the following signs and symptoms: body aches, fever, sweating, runny nose, sneezing, piloerection, yawning, weakness, shivering or trembling, nervousness, restlessness or irritability, diarrhea, nausea or vomiting, abdominal cramps, increased blood pressure, tachycardia. In the neonate, opioid withdrawal may also include: convulsions; excessive crying; hyperactive reflexes (see WARNINGS).
Adverse events associated with the postoperative use of NARCAN (naloxone) are listed by organ system and in decreasing order of frequency as follows:
Cardiac Disorders: pulmonary edema, cardiac arrest or failure, tachycardia, ventricular fibrillation, and ventricular tachycardia. Death, coma, and encephalopathy have been reported as sequelae of these events.
Gastrointestinal Disorders: vomiting, nausea
Nervous System Disorders: convulsions, paresthesia, grand mal convulsion
Psychiatric Disorders: agitation, hallucination, tremulousness
Respiratory Thoracic and Mediastinal Disorders: dyspnea, respiratory depression, hypoxia
Skin and Subcutaneous Tissue Disorders: nonspecific injection site reactions, sweating
Vascular Disorders: hypertension, hypotension, hot flushes or flushing.
See also PRECAUTIONS and DOSAGE AND ADMINISTRATION; Usage in Adults; Postoperative Opioid Depression.
Drug Abuse And Dependence
NARCAN (naloxone) is an opioid antagonist. Physical dependence associated with the use of NARCAN (naloxone) has not been reported. Tolerance to the opioid antagonist effect of NARCAN (naloxone) is not known to occur.
Read the entire FDA prescribing information for Narcan (Naloxone Hydrochloride Injection)