Synagis: adverse event reports filed with FDA

14,497

reports as suspect product

0.1% of all reports · about 644 a year

82

reports, 12 months to June 2026

396 in the 12 months before

79.7%

marked serious by the reporter

78.5% across the class

12.3%

record death among outcomes, as reported

1,777 reports · not verified by FDA

Reports by month, five years

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Synagis reports recording the termmedian drug in respiratory syncytial virus anti-f protein monoclonal antibody

1. Respiratory syncytial virus infection14.2%2,055
2. Pyrexiafever9.6%1,387
3. Bronchiolitis8.2%1,191
4. Deaththe patient died; cause not stated by this term7%1,014
5. Coughcough6.7%971
6. Pneumonialung infection6.1%884
7. Dyspnoeashortness of breath5.1%746
8. Nasopharyngitisa cold4.3%627
9. Vomitingbeing sick4.2%613
10. Influenzaflu3.2%467
11. Bronchitischest infection2.8%411
12. Product dose omission issuea dose was missed2.6%376
13. Diarrhoealoose or frequent stools2.6%370
14. Covid-19COVID-19 infection2.5%360
15. Off label useused for a purpose or in a way not on the label2.5%358
16. Nasal congestiona blocked nose2.4%346
17. Weight decreasedweight loss2.3%334
18. Illness2.3%332
19. Malaisegeneral feeling of being unwell2.3%332
20. Oxygen saturation decreased2.3%327
21. Rhinorrhoeaa runny nose2.2%326
22. Wheezingwheezing2.1%311
23. Respiratory syncytial virus test positive2.1%304
24. Viral infectiona viral infection2%292
25. Respiratory syncytial virus bronchiolitis1.9%275
26. Apnoeapauses in breathing1.9%272
27. Respiratory distressdifficulty breathing1.9%271
28. Rashskin rash1.8%264
29. Respiratory tract infectiona respiratory infection1.7%252
30. Rhinovirus infection1.7%251

Top 30 of 746 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 3 drugs in the respiratory syncytial virus anti-f protein monoclonal antibody class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 16,458 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 61.6% of reports give the United States as the country of the event or reporter.

Reason for use recorded

The indication field is filled in by the reporter and is often blank; shares are of all 14,497 reports.

Drugs most often listed in the same reports

Other products listed in reports where Synagis is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the respiratory syncytial virus anti-f protein monoclonal antibody class

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Synagis as a suspect or interacting product; reports listing it only as a concomitant medication (194) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.