Japanese encephalitis virus vaccine (By injection)

Japanese Encephalitis Virus Vaccine, Inactivated Adsorbed (jap-a-NEEZ en-sef-a-LYTE-is VYE-rus VAX-een, in-AK-ti-vay-ted ad-SORBD)

Prevents Japanese encephalitis.

Brand Name(s):


There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This vaccine is not right for everyone. You should not receive it if you had an allergic reaction to Japanese encephalitis virus vaccine or protamine sulfate.

How to Use This Medicine:


  • Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot into one of your muscles.
  • A nurse or other health provider will give you this medicine.
  • This vaccine requires 2 doses that are given 28 days apart. It is very important that you receive the second dose of the vaccine at least 7 days before possible exposure, such as if you travel out of the country.
  • You might need a booster dose in the future if you travel or could be exposed to Japanese encephalitis again. A booster dose may be given if it has been more than 1 year since you completed the first 2-dose series.
  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
  • Missed dose: If you miss your appointment for the second shot, call your doctor to make another appointment as soon as possible.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some foods and medicines can affect how this vaccine works. Tell your doctor if you are using a medicine that weakens your immune system, including a steroid or cancer medicine.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have a bleeding disorder.
  • This vaccine may not protect everyone who receives it, such as people who have a weak immune system.
  • Japanese encephalitis is spread by mosquitoes. Prevent mosquito bites by using insect repellent and mosquito nets and wearing protective clothing when you are outside.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Fast heartbeat

If you notice these less serious side effects, talk with your doctor:

  • Diarrhea, nausea, vomiting, loss of appetite
  • Headache
  • Irritability, fever
  • Muscle pain
  • Pain, redness, or tenderness where the shot was given

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 11/6/2020

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