Influvac (Influenza Vaccine (Surface Antigen, Inactivated))
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Influvac Used For?
Influvac is a flu vaccine that helps protect you from getting influenza. It contains inactivated pieces from three different types of flu viruses.
Primary Uses
Influvac prevents certain types of influenza (commonly called the flu) in adults and children over 6 months of age. It’s recommended to get vaccinated every year as new flu virus types appear annually.
How It Works
The vaccine works by causing your body to produce its own protection (antibodies) against three different types of influenza virus. Each year, Influvac is updated to contain fragments of the new virus types expected for that flu season.
Important to know: Influvac only protects against the three specific flu virus types used to make the vaccine. It won’t protect you from other flu viruses or common cold infections.
How to Take Influvac
Influvac is given as an injection by a doctor, nurse, or pharmacist. The vaccine is usually given once a year before flu season starts.
Dosage Instructions
Adults and children over 36 months: 0.5 mL injection. Children 6 to 35 months: 0.25 mL injection. Children under 9 years who haven’t been vaccinated before need a second dose at least 4 weeks after the first dose. The injection is usually given in the muscle, but for people with bleeding problems, it may be given under the skin.
What If You Miss a Dose?
If you miss your scheduled vaccination, talk to your doctor, nurse, or pharmacist and arrange another visit as soon as possible.
Never given intravenously: Influvac should never be injected into a vein (intravenously).
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- Pain and discomfort at injection site
- Redness, swelling, bruising at injection site
- Soreness, itching, or hard lump at injection site
- Headache
- Tiredness
- Muscle and joint aches/pains
- Generally feeling unwell
- Shivering
- Fever
Seek immediate medical attention if you experience:
- Swelling of limbs, face, eyes, inside of nose, mouth or throat
- Shortness of breath, breathing or swallowing difficulties
- Hives, itching (especially hands or feet)
- Reddening of skin (especially around ears)
- Severe skin reactions
- Unusual tiredness or weakness that is sudden and severe
Important Warnings
Before receiving Influvac, it’s important to tell your healthcare provider about your medical history and current health status.
Who Should Not Take Influvac
Don’t receive Influvac if you’re allergic to any influenza vaccine or any ingredients in the vaccine, or if you currently have a severe infection or fever. Minor infections like a cold should not be a problem, but discuss this with your healthcare provider.
Medical Conditions to Discuss
Tell your healthcare provider if you’ve had Influvac before and became unwell, ever had Guillain-Barre Syndrome (you may be more likely to develop it again), have immune deficiency conditions, thrombocytopenia, coagulation or bleeding disorders, or have ever fainted when receiving injections.
Pregnancy and Breastfeeding
If you’re pregnant or planning to become pregnant, your healthcare provider will discuss the benefits and risks of receiving Influvac. If you’re breastfeeding, the vaccine is not expected to cause problems for breast-fed babies, but discuss this with your healthcare provider.
Allergic reactions: Signs of allergic reaction include itchy skin rash, shortness of breath, and swelling of face or tongue. Seek immediate medical attention if these occur.
Drug Interactions
Tell your healthcare provider about all medicines you’re taking and any other vaccines you’ve received this year.
- Other vaccines received in the same year
- Any prescription medicines
- Over-the-counter medicines from pharmacy or supermarket
- Health food shop supplements
Alcohol & Driving
Influvac should not normally interfere with your ability to drive or operate machinery, but some people may experience dizziness or light-headedness.
Alcohol
No specific alcohol restrictions mentioned in the source material.
Driving and Operating Machinery
Be careful before driving or using machines until you know how Influvac affects you. Some people may experience dizziness or light-headedness after vaccination. Make sure you know how you react before driving or operating machinery.
Storage
Influvac is usually stored at the pharmacy or doctor’s clinic. If you need to store it, keep it in the refrigerator between 2°C to 8°C. Do not freeze as freezing destroys the vaccine. Keep it where children cannot reach it and in the original pack until use. Ask your pharmacist what to do with expired or unused vaccine.
Overdose Information
Since Influvac is given as a single dose by a healthcare professional, overdose is unlikely. If you have concerns about the vaccination, contact your healthcare provider immediately.
Frequently Asked Questions
The vaccine works by causing your body to produce antibodies against flu viruses. However, the source doesn’t specify exactly how long this takes. A protective immune response may not occur in all people who receive the vaccine.
A minor infection such as a cold should not be a problem, but you should talk to your doctor, nurse, or pharmacist before being vaccinated. However, if you have a severe infection or fever, you should not receive the vaccine.
Your healthcare provider will discuss the benefits and risks of receiving Influvac when pregnant. The decision should be made together with your doctor based on your individual situation.
Yes, influenza vaccination is recommended every year. Each year new types of influenza virus can appear, so Influvac is changed annually to contain fragments of the new virus types expected for that flu season.
Most side effects are mild and clear up within a few days. For less serious side effects like injection site pain or mild flu-like symptoms, speak to your healthcare provider if they worry you. For serious allergic reactions like swelling, breathing difficulties, or severe skin reactions, call your doctor immediately or go to the emergency department.
Yes, Influvac can be used in children 6 months and older. Children 6-35 months receive 0.25 mL, while children over 36 months receive 0.5 mL. Children under 9 years who haven’t been vaccinated before need two doses given at least 4 weeks apart.
The vaccine contains limited quantities of egg protein (ovalbumin or chicken proteins). Do not receive Influvac if you are allergic to any of these ingredients. Discuss your egg allergy with your healthcare provider before vaccination.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.