Influvac Tetra

Leaflet accompanying the packaging: information for the user

Influvac Tetra, suspension for injection in a pre-filled syringe

Influenza vaccine (surface antigen), inactivated
Season 2025/2026

You should carefully read the contents of this leaflet before the vaccine is administered to an adult or child, as it contains important information for the patient.

• You should keep this leaflet, so you can read it again if you need to.
• If you have any further questions, ask your doctor, pharmacist, or nurse.
• This vaccine has been prescribed specifically for the adult or child named on the label. Do not pass it on to others.
• If the adult or child experiences any side effects, including any not listed in this leaflet, tell your doctor, pharmacist, or nurse. See section 4.

Table of contents of the leaflet

• 1. What is Influvac Tetra and what is it used for
• 2. Important information before using Influvac Tetra
• 3. How to use Influvac Tetra
• 4. Possible side effects
• 5. How to store Influvac Tetra
• 6. Contents of the packaging and other information

1. What is Influvac Tetra and what is it used for

Influvac Tetra is a vaccine. This vaccine helps protect adults and children from getting the flu, especially those at risk of complications from the flu. Influvac Tetra is indicated for adults and children from 6 months of age.
The use of the Influvac Tetra vaccine should be in line with official recommendations.
After vaccination with Influvac Tetra, the body's immune system (the body's natural defense system) produces its own defense (antibodies) against the disease. None of the vaccine components cause the flu.
The flu is a disease that can spread rapidly. It is caused by different strains of the virus, which can change every year. For this reason, vaccination of an adult or child may be necessary every year. The highest risk of getting the flu is during the cold months between October and March. If an adult or child has not been vaccinated in the fall, vaccination can be done until spring, as there is still an increased risk of getting the flu during this time. The doctor will determine the best time for vaccination.
Influvac Tetra protects adults and children against the four virus strains contained in the vaccine about 2-3 weeks after vaccination.
The incubation period of the flu in the body is several days, so if an adult or child comes into contact with the virus shortly before or after vaccination, there is a possibility of getting the flu.
The vaccine does not protect adults or children from getting a cold, even though some of its symptoms are similar to those of the flu.

2. Important information before using Influvac Tetra

Tell your doctor, pharmacist, or nurse if any of the following apply to the adult or child who is to receive the vaccine. If in doubt, ask your doctor, pharmacist, or nurse for clarification.

When not to use Influvac Tetra

• if the adult or child is allergic (hypersensitive) to:
• active substances or
• any other component of the Influvac Tetra vaccine (see section 6) or
• any of the components that may be present in very small amounts, such as chicken eggs (egg albumen, chicken proteins), formaldehyde, cetyltrimethylammonium bromide, polysorbate 80, or gentamicin (an antibiotic used to treat bacterial infections)
• if the adult or child has a disease with high fever or acute infection, vaccination should be postponed until recovery.

Warnings and precautions

Before using the Influvac Tetra vaccine, tell your doctor if the adult or child has:

• weakened immune response (due to immune deficiency or taking medications that affect the immune system)
• bleeding or bruising easily.

The doctor will decide whether the adult or child can be vaccinated.
Fainting, feeling faint/weak, or other stress-related reactions may occur before or after any needle injection. If the adult or child has had such a reaction before, they should tell their doctor or nurse.
Tell your doctor if the adult or child is scheduled to have blood tests within a few days of being vaccinated against the flu. In some patients, false-positive blood test results have been observed shortly after flu vaccination.
Like any vaccine, Influvac Tetra may not fully protect all vaccinated patients.

Influvac Tetra and other medicines

• Tell your doctor, pharmacist, or nurse about all vaccines or medicines the adult or child is taking or has recently taken, as well as any medicines they plan to take, including those available without a prescription.
• Influvac Tetra can be used at the same time as other vaccines, but each vaccine should be administered into a different limb. This may increase side effects.
• Immune response may be weakened in the case of concurrent treatment with immunosuppressive medications, such as corticosteroids, cytotoxic medications, or radiation therapy.

Pregnancy and breastfeeding

If the patient is pregnant or breastfeeding, thinks they may be pregnant, or plans to have a child, they should consult their doctor or pharmacist before using this vaccine.
Flu vaccines can be used at any stage of pregnancy. A larger set of safety data is available for the second and third trimesters of pregnancy compared to the first trimester; however, data on the use of flu vaccines from around the world do not indicate that the vaccine has any harmful effects on the fetus or mother.
Influvac Tetra can be used during breastfeeding.
The doctor, pharmacist, or nurse will decide whether the pregnant woman can be vaccinated with Influvac Tetra. Before using any medication, consult a doctor, pharmacist, or nurse.

Driving and using machines

Influvac Tetra has no or negligible influence on the ability to drive and use machines.

Influvac Tetra contains sodium and potassium

The vaccine contains less than 1 mmol of sodium (23 mg) per dose, which means it is "sodium-free".
The vaccine contains less than 1 mmol of potassium (39 mg) per dose, which means it is "potassium-free".

3. How to use Influvac Tetra

Dosage

Adults receive one dose of 0.5 ml.

Use in children and adolescents

Children from 6 months to 17 years of age receive one dose of 0.5 ml.
Children under 9 years of age who have not been previously vaccinated with a seasonal flu vaccine: a second dose of 0.5 ml should be administered at least 4 weeks apart.
Children under 6 months of age: the safety and efficacy of the Influvac Tetra vaccine have not been established.

Method and route of administration

The vaccine is administered by a doctor or nurse intramuscularly or deep subcutaneously.
In case of doubts about the use of the vaccine, consult a doctor, pharmacist, or nurse.

4. Possible side effects

Like any medicine, Influvac Tetra can cause side effects, although not everybody gets them.

In case of the following side effects in an adult or child, contact a doctor immediately – immediate medical attention may be required:

Severe allergic reactions (frequency not known, occurred sporadically during the use of the trivalent Influvac vaccine)

• may require immediate medical attention, characterized by low blood pressure, rapid, shallow breathing, rapid heartbeat with weak pulse, cold, sweaty skin, dizziness, which can lead to fainting (shock)
• swelling most pronounced in the face and neck, including the face, mouth, tongue, throat, or other parts of the body, which can cause difficulty swallowing or breathing (angioedema)

During clinical trials with Influvac Tetra, the following side effects were observed:
Adults and elderly:
Very common: may occur in more than 1 in 10 people

• headache
• feeling tired
• local reaction: pain at the injection site. In elderly people (aged ≥61 years), it is reported as common

Common: may occur in up to 1 in 10 people

• sweating
• muscle pain, joint pain
• general feeling of being unwell, chills
• local reactions: redness, swelling, bruising, induration at the injection site

Uncommon: may occur in up to 1 in 100 people

• fever

Children (from 6 months to 17 years of age):

Side effects that occurred in children from 6 months to 35 months of age:

Very common: may occur in more than 1 in 10 people

• sleepiness
• sweating
• loss of appetite
• diarrhea, vomiting
• irritability/fussiness
• fever
• local reactions: pain, redness

Common: may occur in up to 1 in 10 people

• local reactions: swelling, induration, bruising

Side effects that occurred in children from 3 to 5 years of age:

Very common: may occur in more than 1 in 10 people

• sleepiness
• loss of appetite
• irritability/fussiness
• local reactions: pain at the injection site, redness, swelling, induration at the injection site

Common: may occur in up to 1 in 10 people

• sweating
• diarrhea, vomiting
• fever
• local reaction: bruising

Side effects that occurred in children from 6 to 17 years of age:

Very common: may occur in more than 1 in 10 people

• headache
• nausea, abdominal pain, diarrhea, vomiting
• muscle pain
• fatigue, general feeling of being unwell
• local reactions: pain at the injection site, redness, swelling, induration at the injection site

Common: may occur in up to 1 in 10 people

• sweating
• joint pain
• fever
• chills
• local reaction: bruising

All age groups
In all age groups, most of the above side effects occurred usually within the first 3 days of vaccination and resolved on their own within 1 to 3 days of onset. Generally, these were mild side effects.
In addition to the above side effects, the following side effects have been observed sporadically during the use of the trivalent Influvac vaccine.
Frequency not known

• skin reactions that can affect the whole body, including itching, hives, or rash
• vasculitis that can cause skin rash and, in very rare cases, temporary kidney function disorders
• nerve pain (neuralgia), abnormal sensations such as tingling, pain, heat, and cold (paresthesia), febrile seizures, neurological disorders that can lead to stiffness of the neck, disorientation, numbness, pain, and weakness of the limbs, balance disorders, loss of reflexes, paralysis of part or all of the body (encephalitis and myelitis, neuritis, Guillain-Barré syndrome)
• temporary decrease in platelet count; their low number can lead to increased bruising and bleeding (transient thrombocytopenia), temporary enlargement of cervical, axillary, or inguinal lymph nodes (transient lymphadenopathy).

Reporting side effects
If the adult or child experiences any side effects, including any not listed in this leaflet, tell your doctor, pharmacist, or nurse. Side effects can be reported directly to the Department of Adverse Reaction Monitoring of Medicinal Products of the Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products:
Jerozolimskie Avenue 181C
02-222 Warsaw
tel.: 22 49 21 301
fax: 22 49 21 309
website: https://smz.ezdrowie.gov.pl
Side effects can also be reported to the marketing authorization holder.
By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Influvac Tetra

Store the vaccine out of sight and reach of children.
Do not use this vaccine after the expiry date stated on the carton and on the syringe after EXP. The expiry date refers to the last day of the month.
Store in a refrigerator (2°C - 8°C). Do not freeze.
Store in the original packaging to protect from light.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines that are no longer needed. This will help protect the environment.

6. Contents of the packaging and other information

What Influvac Tetra contains

The active substances are:
Influenza virus surface antigens (inactivated) (hemagglutinin and neuraminidase)
corresponding to the following strains*:
A/Victoria/4897/2022 (H1N1)pdm09–like strain (A/Victoria/4897/2022, IVR-238)
15 micrograms of HA**
A/Croatia/10136RV/2023 (H3N2)–like strain (A/Croatia/10136RV/2023, X-425A)
15 micrograms of HA**
B/Austria/1359417/2021–like strain (B/Austria/1359417/2021, BVR-26)
15 micrograms of HA**
B/Phuket/3073/2013–like strain (B/Phuket/3073/2013, wild type)
15 micrograms of HA**
in a 0.5 ml dose
* grown in chicken embryos from healthy flocks
** hemagglutinin
This vaccine is in line with the recommendations of the World Health Organization (WHO) (for the Northern Hemisphere) and EU recommendations for the 2025/2026 season.
The other ingredients of the vaccine are: potassium chloride, potassium dihydrogen phosphate, disodium phosphate dihydrate, sodium chloride, calcium chloride dihydrate, magnesium chloride hexahydrate, water for injections.

What Influvac Tetra looks like and contents of the pack

Influvac Tetra is a 0.5 ml colorless, clear suspension for injection in a pre-filled syringe (Type I glass) with or without a needle. Each pre-filled syringe can only be used once.
Pack sizes of 1 or 10 pre-filled syringes.
Not all pack sizes may be marketed.

Marketing authorization holder

Viatris Healthcare Limited
Damastown Industrial Park
Mulhuddart
Dublin 15
DUBLIN
Ireland

Manufacturer

Abbott Biologicals B.V.
Veerweg 12
Olst, 8121AA
Netherlands
To obtain more detailed information, contact your local representative of the marketing authorization holder:
Viatris Healthcare Sp. z o.o.
tel. 22 546 64 00

This medicinal product is authorized in the Member States of the European Economic Area and in the United Kingdom (Northern Ireland) under the following names:

Date of last revision of the leaflet:06/2025

The following information is intended for healthcare professionals only:

As with all vaccines administered by injection, the possibility of immediate and appropriate medical treatment and adequate medical supervision should be ensured in case of an anaphylactic reaction after vaccination.
The vaccine should reach room temperature. Shake before use.
Inspect visually before administration.
Do not use the vaccine if the suspension contains contaminants.
Do not mix with other medicinal products in the same syringe.
The vaccine must not be administered intravascularly.
Preferred injection sites for intramuscular administration are the anterolateral thigh (or deltoid muscle if muscle mass is adequate) in children from 6 months to 35 months of age, or the deltoid muscle in children from 36 months of age and in adults.
Identifiability
To improve the identifiability of biological medicinal products, the name and batch number of the administered product should be clearly recorded.
See also section 3: How to use Influvac Tetra