Flublok is part of the Vaccinations class and treats Flu Vaccination. Vaccinations are used to prevent a number of infections, conditions, and diseases, including chickenpox, hepatitis A, hepatitis B, HPV, meningitis, pneumonia, ear infections, rabies, typhoid, rotavirus, flu, and shingles. They work to build immunity and protection in the body. Flublok is only available as a brand name drug. Compare vaccinations.

What is Flublok?

Commonly Used Brand Name(s)Flublok, Flublok 2015-2016 Formula, Flublok 2016-2017 Formula

Therapeutic ClassificationsVaccine




Influenza virus vaccine, recombinant is used to prevent infection caused by the influenza viruses in adults 18 years of age and older. The vaccine works by causing your body to produce its own protection (antibodies) against the disease. It is also known as a “flu shot”.

It is necessary to receive an influenza vaccine injection each year, since influenza infections are usually caused by different kinds of viruses and the protection gained by the vaccine lasts less than a year. The best way to help prevent influenza infections is to get an influenza vaccination each year, usually in early November.

This vaccine is to be given only by or under the supervision of your doctor or other health care professional.

Proper UseTOP

A nurse or other trained health professional will give you this vaccine. This vaccine is given as a shot into one of your muscles, usually in the shoulder area.

You need to get the flu vaccine every year to protect you from the flu.

This medicine comes with a patient information sheet. It is very important that you read and understand this information. Ask your doctor if you have any questions.

Before UsingTOP

In deciding to use a vaccine, the risks of taking the vaccine must be weighed against the good it will do. This is a decision you and your doctor will make. For this vaccine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies have not been performed on the relationship of age to the effects of Flublok® in children 3 to 17 years of age. Safety and efficacy have not been established.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of Flublok® in the elderly.


Pregnancy CategoryExplanation
All TrimestersBAnimal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast FeedingTOP

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug InteractionsTOP

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this vaccine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Receiving this vaccine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Receiving this vaccine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Other InteractionsTOP

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical ProblemsTOP

The presence of other medical problems may affect the use of this vaccine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Guillain-Barré syndrome (GBS, a severe nerve and muscle problem), history of—Use with caution. May cause the symptoms of this condition to return.
  • Immune system problems from a disease or medicine—May not work as well in patients with this condition.


Be sure to notify your doctor of any side effects that occur after you receive this vaccine.

This vaccine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Tell your doctor right away if you have a rash, itching, swelling of the tongue and throat, or troubled breathing after you get the injection.

Influenza virus vaccine may not protect everyone who receives the vaccine. Also, this vaccine will not treat flu symptoms if you already have the virus.

Make sure your doctor knows if you are using a medicine or treatment that weakens your immune system, such as a steroid, radiation, or cancer treatment. This vaccine may not work as well if you are also using these medicines. Your doctor may still want you to get the vaccine because it can give you some protection.

GoodRx is not sponsored by or affiliated with any of the pharmacies identified in its price comparisons. All trademarks, brands, logos and copyright images are property of their respective owners and rights holders and are used solely to represent the products of these rights holders. This information is for informational purposes only and is not meant to be a substitute for professional medical advice, diagnosis or treatment. GoodRx is not offering advice, recommending or endorsing any specific prescription drug, pharmacy or other information on the site. GoodRx provides no warranty for any of the pricing data or other information. Please seek medical advice before starting, changing or terminating any medical treatment.
The information contained in the Truven Health Micromedex products as delivered by GoodRx is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.
The use of the Truven Health products is at your sole risk. These products are provided "AS IS" and "as available" for use, without warranties of any kind, either express or implied. Truven Health and GoodRx make no representation or warranty as to the accuracy, reliability, timeliness, usefulness or completeness of any of the information contained in the products. Additionally, TRUVEN HEALTH MAKES NO REPRESENTATION OR WARRANTIES AS TO THE OPINIONS OR OTHER SERVICE OR DATA YOU MAY ACCESS, DOWNLOAD OR USE AS A RESULT OF USE OF THE THOMSON REUTERS HEALTHCARE PRODUCTS. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR USE ARE HEREBY EXCLUDED. Truven Health does not assume any responsibility or risk for your use of the Truven Health products.