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naloxone (injection)

Pronunciation: nah LOX one

Brand: Evzio

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

Naloxone is used to treat a possible opioid overdose. An opioid overdose can be fatal, and symptoms may include severe drowsiness, pinpoint pupils, slow breathing, or no breathing.

A person caring for you can give the naloxone if you stop breathing or don't wake up. Make sure any person caring for you knows where you keep naloxone and how to use it.

Your caregiver must get emergency help after giving a naloxone injection. You may need another injection every 2 to 3 minutes until emergency help arrives.

What is naloxone?

Naloxone blocks or reverses the effects of opioid medication, including extreme drowsiness, slowed breathing, or loss of consciousness.

Naloxone is used in an emergency situation to treat a possible opioid overdose in an adult or child.

This medicine should not be used in place of emergency medical care for an overdose.

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

What should I discuss with my healthcare provider before receiving naloxone?

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 problems; or
  • you are pregnant or breastfeeding.

Using naloxone while you are pregnant may cause opioid withdrawal effects in your unborn baby. However, having an opioid overdose can be fatal to both mother and baby. It is much more important to treat an overdose in the mother. You must get emergency medical help after using naloxone. Be sure all emergency medical caregivers know that you are pregnant.

If you use opioid medicine while you are pregnant, your baby could become dependent on the drug. This can cause life-threatening withdrawal symptoms in the baby after it is born. Babies born dependent on opioids may need medical treatment for several weeks.

In an emergency, you may not be able to tell caregivers if you are pregnant or breastfeeding. Make sure any doctor caring for your pregnancy or your baby knows you received this medicine.

How is naloxone given?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Naloxone is injected into a muscle or under the skin. 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 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, even if the person wakes up. You may need to perform CPR (cardiopulmonary resuscitation) on the person while you are waiting for emergency help to arrive.

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 inside.

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?

Since naloxone is used when needed, this medicine has no dosing schedule.

What happens if I overdose?

Since naloxone is supplied as the correct dose in a single-dose auto-injector, an overdose is unlikely to occur.

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.

What are the possible side effects of naloxone?

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;
  • goose bumps, shivering;
  • runny nose, yawning; or
  • feeling nervous, restless, or irritable.

Sudden withdrawal symptoms in a baby younger than 4 weeks old may be life-threatening if not treated the right way. Symptoms include crying, stiffness, overactive reflexes, and seizures. Call your doctor or get emergency medical help if you are not sure how to properly give this medicine to a baby.

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.

What other drugs will affect naloxone?

Other drugs may affect 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.

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.

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