Reported Reactions

Drugs

Product name as reported

Sifrol: adverse event reports filed with FDA

1,039 reports list it as a suspect or interacting product, 2004–2021.

1,039
reports as suspect product
0% of all reports · about 47 a year
0
reports, 12 months to June 2026
0 in the 12 months before
98.1%
marked serious by the reporter
57.4% across all reports
8%
record death among outcomes, as reported
83 reports · not verified by FDA

1,039 adverse event reports received by FDA list the product name "Sifrol" as reporters wrote it as a suspect or interacting product, from April 2004 to September 2021. A further 1,046 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 0 reports listed it, and none in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 47 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are hallucination (6.6%), confusional state (6.3%) and somnolence (5.4%). A report can list several reactions, so shares add to more than 100%; 363 different terms appear across these reports. Hallucination is recorded in 6.6% of these reports, against 0.4% of all reports in the database.

98.1% of the reports are marked serious by the reporter; 8% record death among the outcomes and 45.8% record hospitalisation, as reported. 36% of the reports came from physicians, and the largest patient age group is 45 to 64 (21%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

047Jul 2021: 2Aug 2021: 7Sep 2021: 3Oct 2021: 0Nov 2021: 0Dec 2021: 02022Jan 2022: 0Feb 2022: 0Mar 2022: 0Apr 2022: 0May 2022: 0Jun 2022: 0Jul 2022: 0Aug 2022: 0Sep 2022: 0Oct 2022: 0Nov 2022: 0Dec 2022: 02023Jan 2023: 0Feb 2023: 0Mar 2023: 0Apr 2023: 0May 2023: 0Jun 2023: 0Jul 2023: 0Aug 2023: 0Sep 2023: 0Oct 2023: 0Nov 2023: 0Dec 2023: 02024Jan 2024: 0Feb 2024: 0Mar 2024: 0Apr 2024: 0May 2024: 0Jun 2024: 0Jul 2024: 0Aug 2024: 0Sep 2024: 0Oct 2024: 0Nov 2024: 0Dec 2024: 02025Jan 2025: 0Feb 2025: 0Mar 2025: 0Apr 2025: 0May 2025: 0Jun 2025: 0Jul 2025: 0Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 02026Jan 2026: 0Feb 2026: 0Mar 2026: 0Apr 2026: 0May 2026: 0Jun 2026: 0

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

049972004: 1720042005: 212006: 4120062007: 472008: 4120082009: 752010: 4020102011: 222012: 3420122013: 672014: 6920142015: 882016: 7820162017: 842018: 9720182019: 922020: 6920202021: 57

Reactions recorded in the reports

share of Sifrol reports recording the termall reports in the database

  1. Hallucinationseeing or hearing things that are not there6.6%69
  2. Confusional stateconfusion6.3%65
  3. Somnolencedrowsiness5.4%56
  4. Fatiguetiredness4.9%51
  5. Impulse-control disorder4.9%51
  6. Condition aggravatedthe condition being treated got worse4.4%46
  7. Falla fall4.3%45
  8. Deliriumsudden confusion4.2%44
  9. Suicide attempta suicide attempt4.1%43
  10. Insomniadifficulty sleeping3.8%39
  11. Dizzinesslight-headedness or unsteadiness3.7%38
  12. Restlessnessrestlessness3.7%38
  13. Dyskinesiainvoluntary movements3.6%37
  14. Nauseafeeling sick3.5%36
  15. Compulsive shopping3.4%35
  16. Agitationrestlessness3.3%34
  17. Tremorshaking3.3%34
  18. Malaisegeneral feeling of being unwell3.2%33
  19. Depressionlow mood3.1%32
  20. Suicidal ideationthoughts of suicide3.1%32
  21. Drug ineffectivethe medicine did not work as expected3%31
  22. Gambling disorder3%31
  23. Astheniaweakness or lack of energy2.7%28
  24. Pathological gambling2.7%28
  25. Gait disturbancedifficulty walking2.6%27
  26. Oedema peripheralswelling of the legs, ankles or hands2.6%27
  27. Anxietyanxiety2.4%25
  28. Hypotensionlow blood pressure2.3%24
  29. Drug interactionan interaction between medicines2.1%22

Top 30 of 363 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 share of all reports in the database; 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

Death8%83
Life-threatening6.6%69
Hospitalisation (initial or prolonged)45.8%476
Disability6%62
Congenital anomaly0.5%5
Other serious50.4%524
Not serious1.9%20

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 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.5%5
2 to 110.6%6
12 to 170.2%2
18 to 445.6%58
45 to 6421%218
65 to 7419.9%207
75 and over18%187
Age not given34.3%356

Patient sex

Female51.8%538
Male42.7%444
Not given5.5%57

Who reported

Physician36%374
Pharmacist6.9%72
Other health professional28.3%294
Lawyer0.4%4
Consumer or non-health professional22.8%237
Not given5.6%58

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 3.3% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Restless legs syndrome24323.4%
Parkinson's disease24123.2%
Parkinson's disease12812.3%
Parkinsonism111.1%
Extrapyramidal disorder50.5%
Epilepsy30.3%

The indication field is filled in by the reporter and is often blank; shares are of all 1,039 reports.

In context

MeasureSifrolAll reports
Reports as suspect product1,03920,646,523
Share of that pool—0%
Reports, latest 12 months01,332,454
Marked serious98.1%57.4%
Death recorded among outcomes, per 1,000 reports8091
Hospitalisation recorded, per 1,000 reports458213
Consumer-filed share22.8%45.8%
Top term, share of reportsHallucination 6.6%0.4%

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."

Questions about Sifrol reports

How many adverse event reports has FDA received for Sifrol?

1,039 reports list Sifrol as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 0 of them arrived in the latest 12 months. Another 1,046 list it only as a concomitant medication.

What reactions are recorded in Sifrol reports?

hallucination (6.6%), confusional state (6.3%), somnolence (5.4%), fatigue (4.9%) and impulse-control disorder (4.9%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Sifrol was responsible.

How serious are the reports?

98.1% are marked serious by the reporter. Among the outcomes recorded, 8% of reports include death and 45.8% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

physician (36%), other health professional (28.3%) and consumer or non-health professional (22.8%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Sifrol rising?

0 reports in the 12 months to June 2026, and none in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Sifrol was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Sifrol?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

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 Sifrol as a suspect or interacting product; reports listing it only as a concomitant medication (1,046) 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.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.