Energix-B (hepatitis B vaccine [recombinant]) can cause side effects, such as fatigue and injection-site soreness. If you are not able to tolerate Energix-B side effects, talk with your doctor or pharmacist.

Energix-B (hepatitis B vaccine [recombinant]) is a brand-name vaccine prescribed to help prevent infection from the hepatitis B virus.

If you have problems with side effects from Energix-B, talk with your doctor or pharmacist. They can discuss ways to manage side effects or other available treatment options. Do not stop taking Energix-B without consulting your doctor first.

Energix-B can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects persist, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Energix-B in clinical trials:

For more information about some of these side effects, see the “Managing side effects” section.

Mild side effects of Energix-B

Mild side effects can occur with Energix-B use. This list does not include all possible mild side effects of the drug. For more information, you can refer to the drug’s prescribing information.

Mild side effects that have been reported with Energix-B include:

  • fatigue
  • injection site reactions, which may include pain, soreness, swelling, skin color changes, itching, or irritation
  • dizziness
  • headache
  • fever

These side effects may be temporary, lasting a few days to weeks. However, if they continue, worsen, or become too difficult to tolerate, consult your doctor or pharmacist.

Note: If you would like to report a side effect you’ve had with Energix-B, you can do so through the Vaccine Adverse Event Reporting System (VAERS) website or by calling 800-822-7967. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) receive reports made to VAERS.

For more information about some of these side effects, see the “Managing side effects” section.

Energix-B may cause serious side effects. The following list may not include all possible serious side effects of the drug. For more information, you can refer to Energix-B’s prescribing information.

If you develop serious side effects while taking Energix-B, call your doctor right away. If the side effects seem life threatening or you think that you’re having a medical emergency, call 911 or your local emergency number immediately.

Serious side effects and symptoms that have been reported include:

  • syncope (fainting), which may occur along with:
    • jerking movements of your arms or legs
    • numbness
    • vision changes
Allergic reaction

For some people, Energix-B can cause an allergic reaction.

However, it is unclear whether this side effect occurred in the drug’s studies.

In general, symptoms of allergic reactions can be mild or serious.

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening.

While taking Energix-B, you may be able to take steps to make side effects easier to manage.

If you have problems with side effects that do not go away or that worsen, talk with your doctor or pharmacist. They can discuss options for managing side effects.

Fatigue

Fatigue was a common side effect reported in studies of Energix-B. Steps you can take to manage symptoms associated with this side effect include:

  • practicing good sleep hygiene
  • maintaining a well-balanced diet
  • getting regular physical activity

Injection site reactions

Injection site reactions were common side effects reported in studies of Energix-B. Examples of injection site reactions may include pain, soreness, swelling, skin color changes, itching, or irritation.

Steps you can take to manage symptoms associated with this side effect include:

  • taking over-the-counter pain medications
  • applying a cold compress

Here are answers to common questions about Energix-B’s side effects.

Does Energix-B cause long-term side effects?

It’s unlikely. Long-term side effects were not reported in studies of Engerix-B.

If you have concerns about possible long-term side effects from this drug, talk with your doctor or pharmacist.

Are side effects of Engerix-B in children similar to those seen in adults?

Yes, the side effects of Engerix-B in children are similar to those in adults. The most common include soreness at the injection site and fatigue. In infants and children, fatigue may show up as irritability or crying.

Premature infants who receive Engerix-B may have a higher risk of certain side effects, such as breathing problems. Sometimes, the vaccine may be delayed until the infant reaches an appropriate weight or is medically stable.

If you have questions about the use or side effects of Engerix-B in children, talk with a doctor or pharmacist.

Before taking Energix-B, discuss your health history with your doctor. The drug may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.