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: Rarely, this vaccine may cause severe allergic reactions. This is why your doctor may ask you to stay in the office for about 30 minutes after having the vaccine so that you can get medical care if you experience an allergic reaction. If you notice signs of a severe allergic reaction (hives; trouble breathing or swallowing; or swelling of the lips, face, throat, or tongue), get medical attention immediately.
Asthma: People who have severe asthma or who have experienced wheezing within the past 7 days should not receive this medication.
Guillain-Barré syndrome: Guillain-Barré syndrome is a rare condition that affects the central nervous system and is thought to be triggered by viral infections and in rare cases, vaccination. When treated quickly, the majority of people affected fully recover. People who have had Guillain-Barré syndrome within 6 months of a vaccination should discuss the risks and benefits of receiving this medication with their doctor.
Immune system: As with any vaccine, influenza vaccine may not be as effective for those who have a weakened immune system (e.g., people on chemotherapy, people who have had an organ transplant, or people with HIV). Also, this vaccine contains live, inactivated virus and people who receive this vaccine may pass the virus on to people with a weakened immune system. If you have received this vaccine, avoid contact with people who have a severely weakened immune system (e.g., people who have received a bone marrow transplant and are in isolation) for at least 2 weeks after receiving the vaccine.
Vaccine protection: As with any vaccine, this vaccine may not protect 100% of people who receive it. The vaccine only provides protection against certain strains of the flu virus (i.e., the ones from which it was prepared, or ones that are closely related).
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if influenza vaccine (intranasal spray) passes into breast milk. If you are a breast-feeding mother and are going to receive this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: This medication is not recommended for children under 2 years of age, as they are at an increased risk of experiencing wheezing. Also, children under 18 years of age who are taking acetylsalicylic acid (ASA) or ASA-related medications should not receive this vaccine due to the risk of developing Reye's syndrome (a severe but rare condition that affects the nervous system and liver).