YF-Vax

Brand Name

YF-Vax

Common Name

yellow fever vaccine

In this drug factsheet:

• How does this medication work? What will it do for me?
• How should I use this medication?
• What form(s) does this medication come in?
• Who should NOT take this medication?
• What side effects are possible with this medication?
• Are there any other precautions or warnings for this medication?
• What other drugs could interact with this medication?

How does this medication work? What will it do for me?

Yellow fever vaccine belongs to a group of medications known as vaccines. It is used to prevent yellow fever caused by a flavivirus and passed to humans who are bitten by an infected mosquito. Infection from this virus attacks the liver and can be deadly.

The yellow fever vaccine is recommended for adults and children 9 months of age and older who are travelling to or living in areas where yellow fever exists. Vaccination is also recommended for laboratory workers who routinely handle specimens that contain or are believed to contain yellow fever. The yellow fever vaccine increases your defenses against infection by the virus by stimulating the production of your own antibodies. These antibodies remain in the body until they are needed to fight off the virus responsible for yellow fever.

Your doctor may have suggested this vaccine for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are receiving this vaccine, speak to your doctor.

How should I use this medication?

The usual dose of this vaccine is 0.5 mL given as subcutaneous (under the skin) injection. A second dose, or "booster" dose, may be given after 10 years to boost the levels of antibodies in the blood, however, evidence demonstrates that the effectiveness of the yellow fever vaccine may last for at least 30 to 35 years.

This vaccine is given by a health care professional in a doctor's office, hospital, or clinic.

It takes 10 days for immunity to develop after using this vaccine, so it is important that this vaccine be given at least 10 days before entering an area where you may come into contact with the virus that causes yellow fever.

This medication is stored in the refrigerator and should not be allowed to freeze.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

What form(s) does this medication come in?

When reconstituted with saline provided with the vaccine, each 0.5 mL dose of slightly pink-brown suspension contains at least 4.74 log10 plaque-forming units of yellow fever virus strain 17D-204. Nonmedicinal ingredients: sorbitol, gelatin, and sodium chloride injection USP.

Latex free.

Who should NOT take this medication?

Do not take this medication if you:

• are allergic to yellow fever virus or any ingredients of the medication
• are allergic to eggs, chicken protein, or latex
• are taking medications that reduce the effectiveness of the immune system
• have any conditions that affect the immune system (e.g., HIV/AIDS, leukemia lymphoma)
• have had your thymus gland removed, or have a history of problems with the thymus such as thymoma or myasthenia gravis

Do not give this medication to infants under 9 months of age.

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• fever
• headache
• nausea
• pain, redness, or swelling at the injection site

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• hives
• muscle aches
• rash

Stop taking the medication and seek immediate medical attention if any of the following occur:

• confusion
• high fever with headache
• seizures
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Allergic reactions: As with any vaccine, allergic reactions are possible with the yellow fever vaccine. Your doctor may want you to remain in the clinic or office for a period of time after receiving the vaccine, to ensure that you do not develop an allergic reaction.

Immune system: As with any vaccine, this vaccine may not be as effective for people with a weakened immune system (e.g., people with AIDS or cancer, people taking antirejection medications after an organ transplant, people receiving chemotherapy, people taking any medication that suppresses the immune system). If you or your child has a weakened immune system, the doctor may decide to postpone the vaccine until the immune system recovers.

Infection or fever: This vaccine should not be given to anyone who has an active infection or an illness associated with fever, unless the doctor decides that the benefits outweigh the risks.

Vaccine protection: As with any vaccine, this vaccine may not protect 100% of people who receive it and may not prevent infection for people already infected with the virus.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks.

Breast-feeding: It is not known if yellow fever vaccine passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children less than 9 months old. Infants less than 9 months old are at an increased risk of developing encephalitis as a result of receiving this vaccine.

Seniors: People over the age of 60 may be more at risk of developing complications from this vaccine.

What other drugs could interact with this medication?

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

All material copyright MediResource Inc. 1996 – 2025. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/YF-Vax