Synagis (palivizumab) is a monoclonal antibody. It's given to prevent serious respiratory syncytial virus (RSV) infections in infants and young children who are at high risk for severe illness. Synagis (palivizumab) is injected into the muscle monthly, starting right before and continuing throughout the RSV season. Some of the more common side effects of this medication include fever and rash.
Prevention of serious respiratory syncytial virus (RSV) infections for:
Babies born premature and are 6 months or younger at the start of RSV season
Children diagnosed with bronchopulmonary dysplasia (BPD) within the last 6 months, and are 2 years or younger at the start of RSV season
Children with congenital heart disease (CHD) and are 2 years or younger at the start of RSV season
Synagis (palivizumab) is an injection of monoclonal antibodies that can recognize the respiratory syncytial virus (RSV). If RSV enters the body, these antibodies can stop the virus from entering your cells and spreading. This means that RSV is less likely to cause serious lung problems.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
More common
Bluish color of the fingernails, lips, skin, palms, or nail beds
blurred vision
confusion
difficulty with breathing
difficulty with swallowing
dizziness
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
fast heartbeat
hives or welts
irregular, fast or slow, or shallow breathing
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
loss of strength or energy
muscle pain or weakness
redness of the skin
shortness of breath
skin rash
sweating
tightness in the chest
unresponsiveness
unusual tiredness or weakness
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Lowers the risk of serious RSV illness
Not known to affect how well vaccines work
Given monthly during RSV season, instead of once a year, like its alternative
Can't treat RSV infections (only prevents)
Synagis (palivizumab) is injected monthly into the muscle during the season when respiratory syncytial virus (RSV) is most active. The RSV season can vary depending on the climate you live in. Ask your provider how long your local RSV season lasts so you know when your child can stop receiving Synagis (palivizumab) injections.
One of the more common side effects from Synagis (palivizumab) is fever. If your child has a fever, you can give them cool compresses and dress them in light clothing to keep cool. Ask your child's provider if it's safe for your child to take acetaminophen (Tylenol) or ibuprofen (Advil) to treat a fever.
If your child develops an RSV infection, they should still continue to receive Synagis (palivizumab) injections for the rest of the RSV season because it's possible to get RSV more than once.
Early symptoms of RSV are similar to other infections and include runny nose, low appetite, and a cough that might turn into wheezing. If your child develops these symptoms (especially during RSV season), contact their provider right away. While Synagis (palivizumab) can lower the risk of serious RSV illness, some children can still become seriously sick.
Synagis (palivizumab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
In some rare cases, children receiving Synagis (palivizumab) have had serious allergic reactions, including hives, itching, sudden drop in blood pressure, trouble breathing, and swelling of the face and throat. It can happen during the first dose of Synagis (palivizumab) or any of the following doses. If your child experiences a serious allergic reaction to Synagis (palivizumab), they should never receive the medication again.
Risk factors: Low platelets | History of clotting problems
Synagis (palivizumab) is given as an injection into the muscle and should be used with caution in children with certain blood problems. Talk to your provider if your child has a history of low platelets or bleeding problems.
Once-a-month Synagis (palivizumab) is only studied for prevention of RSV, not for treatment. If your child has developed RSV, however, you should still continue to get Synagis (palivizumab) monthly because it's possible to get RSV more than once a season.
Your child's provider will determine the dose based on your child's body weight.
The typical dose is 15 mg/kg injected into the muscle monthly. Your child will receive the first dose before the start of the RSV season and then once a month throughout the RSV season (fall, winter, spring).
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. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Previous serious allergic reaction to Synagis (palivizumab)
Prevention of serious respiratory syncytial virus (RSV) infections for:
Babies born premature and are 6 months or younger at the start of RSV season
Children diagnosed with bronchopulmonary dysplasia (BPD) within the last 6 months, and are 2 years or younger at the start of RSV season
Children with congenital heart disease (CHD) and are 2 years or younger at the start of RSV season
Newborns and infants during or entering their first RSV season
Children up to 24 months old at risk for severe RSV illness through their second RSV season
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American Lung Association. (2024). Learn about bronchopulmonary dysplasia.
Brady, M. T., et al. (2014). Updated guidance for palivizumab prophylaxis among infants and young children at increased risk of hospitalization for respiratory syncytial virus infection. Pediatrics.
Centers for Disease Control and Prevention. (2024). Surveillance of RSV.
Swedish Orphan Biovitrum AB (publ). (2021). Synagis- palivizumab injection, solution [package insert]. DailyMed.
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