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Evzio (injection)

Generic Name: naloxone (injection) (nah LOX one)
Brand Name: Evzio

Medically reviewed on September 12, 2017

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.

Important Information

In an emergency situation it may not be possible to tell your caregivers about your health conditions. Make sure any doctor caring for you afterward knows you have received this medicine.

Before taking this medicine

You should not be treated with naloxone if you are allergic to it.

If possible before you receive a naloxone injection, 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)

What other drugs will affect naloxone?

Other drugs may interact with naloxone, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

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.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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