Drugs › Phosphodiesterase 3 inhibitor
Generic name
Cilostazol: adverse event reports filed with FDA
1,512 reports list it as a suspect or interacting product, 2004–2026. Class: Phosphodiesterase 3 inhibitor.
- 1,512
- reports as suspect product
- 0% of all reports · about 67 a year
- 31
- reports, 12 months to June 2026
- 32 in the 12 months before
- 89%
- marked serious by the reporter
- 65.3% across the class
- 17.6%
- record death among outcomes, as reported
- 266 reports · not verified by FDA
Between February 2004 and May 2026, 1,512 adverse event reports received by FDA list cilostazol, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (4,653) are left out of every figure here.
In the 12 months to June 2026, 31 reports listed it, close to the 32 of 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 67 reports a year and 0% of the 20,646,523 reports in the database, and 56.7% of the reports for the phosphodiesterase 3 inhibitor class. How many people take it is not in the data, so a count is not a rate of occurrence.
Reporters most often recorded drug interaction (5.4%), headache (3.7%) and anaemia (3%). A report can list several reactions, so shares add to more than 100%; 420 different terms appear across these reports. Drug interaction is recorded in 5.4% of these reports, a larger share than in the median phosphodiesterase 3 inhibitor drug (2.7%).
89% of the reports are marked serious by the reporter (65.3% across the class); 17.6% record death among the outcomes and 48.9% record hospitalisation, as reported. 32.7% of the reports came from physicians, and the largest patient age group is 75 and over (35.1%). 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
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 Cilostazol reports recording the termmedian drug in phosphodiesterase 3 inhibitor
- Drug interactionan interaction between medicines5.4%81
- Headachehead pain3.7%56
- Anaemialow red blood cells3%46
- Diarrhoealoose or frequent stools3%45
- Hypotensionlow blood pressure3%45
- Vomitingbeing sick3%45
- Dizzinesslight-headedness or unsteadiness2.8%42
- Deaththe patient died; cause not stated by this term2.7%41
- Drug ineffectivethe medicine did not work as expected2.7%41
- Nauseafeeling sick2.7%41
- Tachycardiafast heart rate2.6%40
- Palpitationsawareness of the heartbeat2.3%35
- Cerebral infarction2.2%34
- Falla fall2.2%34
- Dyspnoeashortness of breath2.2%33
- Gastrointestinal haemorrhagebleeding in the stomach or bowel2.2%33
- Cerebral haemorrhage2.1%31
- Cardiac failureheart failure2%30
- Atrial fibrillationan irregular heart rhythm1.9%29
- Condition aggravatedthe condition being treated got worse1.9%28
- Off label useused for a purpose or in a way not on the label1.9%28
- Loss of consciousnesspassing out1.8%27
- Pneumonialung infection1.7%25
- Melaenablack tarry stools1.5%23
- Astheniaweakness or lack of energy1.5%22
- Myocardial infarctionheart attack1.5%22
- Intentional overdosea deliberate overdose1.4%21
- Pyrexiafever1.4%21
- Ventricular fibrillationa chaotic rhythm from the lower heart chambers1.3%20
- Electrocardiogram QT prolongeda QT prolongation on the ECG1.3%19
Top 30 of 420 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 2 drugs in the phosphodiesterase 3 inhibitor 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 2,669 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
Patient age
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 20% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Cerebral infarction | 177 | 11.7% |
| Intermittent claudication | 107 | 7.1% |
| Antiplatelet therapy | 84 | 5.6% |
| Peripheral arterial occlusive disease | 60 | 4% |
| Peripheral vascular disorder | 30 | 2% |
| Ischaemic stroke | 29 | 1.9% |
The indication field is filled in by the reporter and is often blank; shares are of all 1,512 reports.
In context
| Measure | Cilostazol | Phosphodiesterase 3 inhibitor | All reports |
|---|---|---|---|
| Reports as suspect product | 1,512 | 2,669 | 20,646,523 |
| Share of that pool | — | 56.7% | 0% |
| Reports, latest 12 months | 31 | — | 1,332,454 |
| Marked serious | 89% | 65.3% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 176 | 115 | 91 |
| Hospitalisation recorded, per 1,000 reports | 489 | 348 | 213 |
| Consumer-filed share | 14% | 34.6% | 45.8% |
| Top term, share of reports | Drug interaction 5.4% | median 2.7% | 0.8% |
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 phosphodiesterase 3 inhibitor class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Ohtuvayre | brand | 1,157 | 913 | 34.4% |
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.
Questions about Cilostazol reports
How many adverse event reports has FDA received for Cilostazol?
1,512 reports list Cilostazol as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 31 of them arrived in the latest 12 months. Another 4,653 list it only as a concomitant medication.
What reactions are recorded in Cilostazol reports?
drug interaction (5.4%), headache (3.7%), anaemia (3%), diarrhoea (3%) and hypotension (3%). 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 Cilostazol was responsible.
How serious are the reports?
89% are marked serious by the reporter. Among the outcomes recorded, 17.6% of reports include death and 48.9% 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 (32.7%), other health professional (22.6%) and not given (22.6%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Cilostazol rising?
31 reports in the 12 months to June 2026, close to the 32 of 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 Cilostazol 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 Cilostazol?
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 Cilostazol as a suspect or interacting product; reports listing it only as a concomitant medication (4,653) 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.