Medication Search​ - Synagis

Explore the medications listed in our database.


Common Name:



How does Synagis work? What will it do for me?

Palivizumab belongs to the class of medications known as monoclonal antibodies. Antibodies are used to protect people against infections. Palivizumab is used to prevent serious respiratory (lung) infections caused by a virus called respiratory syncytial virus (RSV). It is used for babies and children who have a high risk of serious lung infections due to RSV, such as those born prematurely or those with heart or lung disease.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop receiving this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

What form(s) does Synagis come in?

Lyophilized Powder

Synagis Lyophilized Powder is no longer being manufactured for sale in Canada and is no longer available under any brand names. This product information is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.

Solution for Injection

50 mg
Each 0.5 ml of solution for injection contains palivizumab 50 mg. Nonmedicinal ingredients: chloride, glycine, histidine, and water for injection

100 mg
Each mL of solution for injection contains palivizumab 100 mg. Nonmedicinal ingredients: chloride, glycine, histidine, and water for injection.

How should I use Synagis?

The usual recommended dose is 15 mg per kilogram of body weight, based on the child’s body weight. It is given as an injection into a muscle (usually the thigh muscle) once a month during the RSV season (i.e., the times of the year when the risk of RSV is high in your community).

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

The RSV season often starts in the fall and continues until spring, although it can also occur at other times of the year. If possible, the first injection should be given before the RSV season starts. The injection will be given by a qualified health care professional.

It is important that this medication be given exactly as recommended by your doctor. If your child misses an appointment to receive palivizumab, contact your doctor as soon as possible to reschedule your appointment. Each injection protects your child for about one month, so it is important to continue regular monthly injections during the RSV season, as recommended by your doctor.

If you are responsible for bringing palivizumab to the appointment, store this medication in the refrigerator, do not freeze, and keep out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take Synagis?

Do not take palivizumab if you:

  • are allergic to palivizumab or any ingredients of the medication
  • are allergic to medications that contain humanized monoclonal antibodies

What side effects are possible with Synagis?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • constipation
  • fever
  • gas
  • redness, swelling, or pain at the injection site

Although most of these side effects listed below don’t happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • changes in feeding habits
  • changes in heart rate
  • colds, sore throat, or runny nose
  • cough
  • diarrhea
  • nervousness or irritability
  • rash
  • signs of anemia (e.g., pale skin, decreased energy, fatigue)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • signs of lung infection (e.g., continuing cough, difficulty breathing, fever, irritability, headache, skin turning blue, weakness)
  • swelling of arms or legs (edema)
  • symptoms of an ear infection (e.g., pain in the ear, tugging on the ear, irritability, frequent crying, trouble sleeping, fluid draining from the ear)
  • vomiting
  • white patches in the mouth or throat

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • pauses in breathing or breathing difficulties
  • seizures
  • symptoms of a serious allergic reaction (e.g., hives, swelling of the face or throat, difficulty breathing)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for Synagis?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies your child may have, any medications your child is taking, and any other significant facts about your child’s health. These factors may affect how they should use this medication.

Acute infection or fever: A palivizumab injection may be delayed if your child is feeling unwell or has a fever due to an infection.

Allergic reactions: Very rarely, palivizumab may cause a serious allergic reaction. If your child develops hives, difficulty breathing, or swelling of the face or throat, seek medical attention immediately.

Bleeding disorders: Palivizumab is given by injection into the muscle. This can cause bleeding at the injection site when the child receiving the injection has a bleeding disorder. If your child has a bleeding disorder, discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

The doctor should monitor your child if your child has a bleeding disorder and is receiving palivizumab.

Use by adults: This medication is intended for use by infants and children. The safety and effectiveness of palivizumab for use by adults have not been established.

Pregnancy: This medication is not intended for adult use. Its safety and effectiveness when used by pregnant women are not known.

Breast-feeding: This medication is not intended for adult use. Its safety and effectiveness when used by breast-feeding women are not known.

What other drugs could interact with Synagis?

Specific drug interaction studies have not been conducted with palivizumab. However, since palivizumab is specific for RSV, it is not expected to interfere with the immune response to vaccines, including live viral vaccines.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications your child is taking. Also tell them about any supplements your child takes. Depending on your child’s specific circumstances, your doctor may want your child to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: