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naloxone

Pronunciation

Generic Name: naloxone (nah LOX one)
Brand Name: Evzio, Narcan

What is naloxone?

Naloxone blocks or reverses the effects of opioid medication, including extreme drowsiness, slowed breathing, or loss of consciousness. An opioid is sometimes called a narcotic.

Naloxone is used to treat a narcotic overdose in an emergency situation. This medicine should not be used in place of emergency medical care for an overdose.

Naloxone is also used to help diagnose whether a person has used an overdose of an opioid.

Naloxone may also be used for purposes not listed in this medication guide.

What is the most important information I should know about naloxone?

In an emergency situation it may not be possible before you are treated to tell your caregivers about your health conditions or if you are pregnant or breast feeding. Make sure any doctor caring for you afterward knows that you have received this medication.

What should I discuss with my health care provider before receiving naloxone?

You should not receive this medicine if you are allergic to naloxone.

To make sure naloxone is safe for you, tell your doctor if you have:

  • heart disease.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant.

It is not known whether naloxone passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

In an emergency situation it may not be possible to tell your caregivers if you are pregnant or breast feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received this medicine.

How is naloxone given?

Naloxone is injected into a muscle, under the skin, or into a vein through an IV. The injection may be given by a healthcare provider, emergency medical provider, or a family member or caregiver who is trained to properly give a naloxone injection.

If you are a caregiver or family member giving a naloxone injection, read all instructions when you first get this medicine. If provided, use the "trainer" device to practice giving an injection so you will know how to do it in an emergency. Ask your doctor or pharmacist if you have any questions.

Be sure you know how to recognize the signs of an opioid overdose in the person you are caring for. Overdose symptoms may include:

  • slowed breathing, or no breathing;

  • very small or pinpoint pupils in the eyes;

  • slow heartbeats; or

  • extreme drowsiness, especially if you are unable to wake the person from sleep.

Even if you are not sure an opioid overdose has occurred, if the person is not breathing or is unresponsive, give the naloxone injection right away and then seek emergency medical care.

Do not assume that an overdose episode has ended if symptoms improve. You must get emergency help after giving a naloxone injection.

Naloxone injected into a muscle is given in the outer thigh. In an emergency, you may give an injection through the person's clothing.

After injecting naloxone, stay with the person and watch for continued signs of overdose. You may need to give another injection every 2 to 3 minutes until emergency help arrives. Follow all medication instructions carefully.

Each Evzio auto-injector is for one use only. Throw away after one use, even if there is still some medicine left in it after injecting a dose.

Store at room temperature away from moisture and heat. Keep the auto-injector in its outer case until you are ready to use it. Do not use the medicine if it has changed colors or has particles in it. Call your pharmacist for new medication.

What happens if I miss a dose?

Because you will receive naloxone in an emergency situation, you are not likely to miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using naloxone?

Avoid leaving a person alone after giving him or her a naloxone injection. An overdose can impair a person's thinking or reactions.

Naloxone side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Because naloxone reverses opioid effects, this medicine may cause sudden withdrawal symptoms such as:

  • nausea, vomiting, diarrhea, stomach pain;

  • fever, sweating, body aches, weakness;

  • tremors or shivering, fast heart rate, pounding heartbeats, increased blood pressure;

  • feeling nervous, restless, or irritable;

  • goosebumps, shivering;

  • runny nose, yawning; or

  • (in babies younger than 4 weeks old) seizures, crying, stiffness, overactive reflexes.

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.

See also: Side effects (in more detail)

Naloxone dosing information

Usual Adult Dose for Opioid Overdose:

Initial dose: 0.4 mg to 2 mg IV; alternatively, may give IM or subcutaneously
-If desired response is not obtained, doses should be repeated at 2 to 3 minute intervals
-If no response is observed with a total dose of 10 mg, the diagnosis of opioid-induced or partial opioid-induced toxicity should be questioned

Auto-injector: For emergency use in the home or other non-medical setting
-Administer 0.4 mg (1 actuation) IM or subcutaneously into the anterolateral aspect of the thigh (through clothing if necessary)
-If desired response is not achieved, a second dose may be administered after 2 or 3 minutes; additional doses may be administered every 2 to 3 minutes until emergency medical assistance arrives

Nasal Spray:
-Administer 1 spray intranasally into 1 nostril
-If desired response is not achieved after 2 or 3 minutes, give a second dose intranasally into alternate nostril; additional doses may be administered every 2 to 3 minutes in alternating nostrils until emergency medical assistance arrives

Comments:
-IV route is recommended in emergency situations since it has the most rapid onset of action.
-The duration of action of some opioids exceed that of this drug, therefore, repeat doses may be needed; the need for repeat doses will depend on the amount, type, and route of administration of the opioid being antagonized.
-Patients should remain under continued surveillance; if a patients responds and relapses back into respiratory depression, additional doses should be given.
-Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance.

Use: For the emergency treatment of known or suspected opioid overdose as manifested by respiratory and/or central nervous system depression.

Usual Adult Dose for Reversal of Opioid Sedation:

Initial dose: 0.1 to 0.2 mg IV at 2 to 3 minute intervals to the desired degree of reversal
-Supplemental doses administered IM have been shown to produce a longer lasting effect

Intravenous Infusion:
-A concentration of 0.004 mg/mL may be administered by IV infusion; titrate in accordance with patient's response

Comments:
-For the partial reversal of opioid depression following the use of opioids during surgery, smaller doses of naloxone are usually sufficient; larger than necessary doses may result in significant reversal of analgesia and increases in blood pressure.

Use: For the complete or partial reversal of opioid depression including respiratory depression, induced by natural and synthetic opioids and certain mixed agonist-antagonist analgesics.

Usual Pediatric Dose for Opioid Overdose:

Neonates:
Initial dose: 0.01 mg/kg IV, IM, or subcutaneously; repeat dose every 2 to 3 minutes as needed

Children:
Initial dose: 0.01 mg/kg IV; if desired response is not obtained, may give 0.1 mg/kg IV
-If IV route is not available may give IM or subcutaneously in divided doses

Auto-injector: For emergency use in the home or other non-medical setting
-Administer 0.4 mg (1 actuation) IM or subcutaneously into the anterolateral aspect of the thigh (through clothing if necessary); if desired response is not achieved, a second dose may be administered after 2 or 3 minutes; additional doses may be administered every 2 to 3 minutes until emergency medical assistance arrives
-Under 1 year of age: Thigh muscle should be pinched while administering injection

Nasal Spray:
-Administer 1 spray intranasally into 1 nostril
-If desired response is not achieved after 2 or 3 minutes, give a second dose intranasally into alternate nostril; additional doses may be administered every 2 to 3 minutes in alternating nostrils until emergency medical assistance arrives

Comments:
-Neonatal opioid withdrawal syndrome may be life-threatening and should be treated according to protocols developed by neonatology experts.
- To avoid precipitating opioid withdrawal symptoms, consider use of a naloxone product that can be dosed according to weight and titrated to effect.
-The duration of action of some opioids will exceed that of this drug, therefore, repeat doses may be needed; the need for repeat doses will depend on the amount, type, and route of administration of the opioid being antagonized.
-Patients should remain under continued surveillance; if a patients responds and relapses back into respiratory depression, additional doses should be given.
-Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance.

Use: For the emergency treatment of known or suspected opioid overdose as manifested by respiratory and/or central nervous system depression.

Usual Pediatric Dose for Reversal of Opioid Sedation:

Neonates:
Initial dose: 0.01 mg/kg IV, IM or subcutaneously at 2 to 3 minute intervals to the desired degree of reversal

Children: 0.005 mg to 0.01 mg IV at 2 to 3 minute intervals to the desired degree of reversal

Intravenous Infusion:
-A concentration of 0.004 mg/mL may be administered by IV infusion; titrate in accordance with patient's response

Comments:
-For the partial reversal of opioid depression following the use of opioids during surgery, smaller doses of naloxone are usually sufficient; larger than necessary doses may result in significant reversal of analgesia and increases in blood pressure.

Use: For the complete or partial reversal of opioid depression including respiratory depression, induced by natural and synthetic opioids and certain mixed agonist-antagonist analgesics.

What other drugs will affect naloxone?

Other drugs may interact with naloxone, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about naloxone.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 3.04. Revision Date: 2015-08-15, 2:17:37 AM.

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