Evzio Side Effects Center

Last updated on RxList: 11/22/2021
Evzio Side Effects Center

What Is Evzio?

Evzio (naloxone hydrochloride injection) is an opioid antagonist used for the emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression.

What Are Side Effects of Evzio?

Common side effects of Evzio include low or high blood pressure, abnormal heart rhythm, shortness of breath, fluid in the lungs, and cardiac arrest. Sudden opioid withdrawal symptoms are also a side effect of Evzio, and include:

  • body aches
  • fever
  • sweating
  • runny nose
  • sneezing
  • goose bumps
  • yawning
  • weakness
  • shivering or trembling
  • nervousness
  • restlessness
  • irritability
  • diarrhea
  • nausea
  • vomiting
  • stomach cramping
  • increased blood pressure, and
  • increased heart rate

Dosage for Evzio

Evzio comes in a pre-filled auto-injector. Each Evzio delivers 0.4 mg naloxone hydrochloride injection (0.4 mL).

What Drugs, Substances, or Supplements Interact with Evzio?

Evzio may interact with other drugs. Tell your doctor all medications and supplements you use.

Evzio During Pregnancy or Breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant before using Evzio. It may cause withdrawal symptoms in a newborn. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding. Withdrawal symptoms may occur if you suddenly stop taking this medication.

Additional Information

Our Evzio (naloxone hydrochloride injection) 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.


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Evzio Consumer Information

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.


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Evzio Professional Information


The following serious adverse reactions are discussed elsewhere in the labeling:

  • Precipitation of Severe Opioid Withdrawal [see WARNINGS AND PRECAUTIONS]

Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to the rates in the clinical studies of another drug and may not reflect the rates observed in practice.

The following adverse reactions were observed in EVZIO clinical studies. In two pharmacokinetic studies with a total of 54 healthy adult subjects exposed to 0.4 mg EVZIO, 0.8 mg EVZIO (two 0.4 mg EVZIOs) or 2 mg EVZIO, adverse reactions occurring in more than one subject were dizziness and injection site erythema.

The following adverse reactions have been identified during post-approval use of naloxone hydrochloride in the post-operative setting. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: 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 naloxone hydrochloride in post-operative patients have resulted in significant reversal of analgesia and have caused agitation [see WARNINGS AND PRECAUTIONS].

Other events that have been reported in post-marketing use of EVZIO include agitation, disorientation, confusion, and anger.

Abrupt reversal of opioid effects in persons who were physically dependent on opioids has precipitated an acute withdrawal syndrome. Signs and symptoms have included: 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 signs and symptoms also included: convulsions, excessive crying, hyperactive reflexes [see WARNINGS AND PRECAUTIONS].

Read the entire FDA prescribing information for Evzio (Naloxone Hydrochloride Auto-injector for Injection)

© Evzio Patient Information is supplied by Cerner Multum, Inc. and Evzio Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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