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Cilostazol Side Effects

Medically reviewed by Last updated on Feb 5, 2024.

Applies to cilostazol: oral tablet.


Oral route (Tablet)

Cilostazol is contraindicated in congestive heart failure of any severity. Cilostazol and many of its metabolites inhibit phosphodiesterase III. Several drugs with this pharmacologic effect have resulted in decreased survival compared with placebo in patients with class III to IV congestive heart failure.

Serious side effects of Cilostazol

Along with its needed effects, cilostazol 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 immediately if any of the following side effects occur while taking cilostazol:

More common

Less common

Incidence not known

Get emergency help immediately if any of the following symptoms of overdose occur while taking cilostazol:

Symptoms of overdose

Other side effects of Cilostazol

Some side effects of cilostazol 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:

More common

Less common

Incidence not known

For Healthcare Professionals

Applies to cilostazol: oral tablet.


The most frequent adverse reactions resulting in discontinuation of therapy were headache, palpitation, and diarrhea.[Ref]

Nervous system

Very common (10% or more): Headache (up to 34%), dizziness (up to 10%)

Frequency not reported: Tinnitus

Postmarketing reports: Intracranial hemorrhage, cerebral hemorrhage, cerebrovascular accident, extradural hematoma, subdural hematoma


Very common (10% or more): Diarrhea (up to 19%), abnormal stools (up to 15%)

Common (1% to 10%): Dyspepsia, abdominal pain

Frequency not reported: Melena

Postmarketing reports: Gastrointestinal hemorrhage, vomiting, flatulence, nausea[Ref]


Very common (10% or more): Infection (up to 14%)

Postmarketing reports: Anaphylaxis, angioedema, hypersensitivity[Ref]


Very common (10% or more): Rhinitis (up to 12%), pharyngitis (up to 10%)

Frequency not reported: Epistaxis

Postmarketing reports: Pulmonary hemorrhage, interstitial pneumonia[Ref]


Very common (10% or more): Palpitation (up to 10%)

Common (1% to 10%): Tachycardia

Frequency not reported: Atrial fibrillation, heart failure, myocardial infarction, nodal arrhythmia, supraventricular tachycardia, ventricular extrasystoles, ventricular tachycardia, left ventricular outflow obstruction

Postmarketing reports: Torsade de pointes, QTc prolongation, angina pectoris, hot flushes, blood pressure increased, subacute stent thrombosis, hypertension[Ref]


Common (1% to 10%): Peripheral edema

Frequency not reported: Fever, generalized edema, malaise

Postmarketing reports: Pain, chest pain[Ref]


Frequency not reported: Anorexia, hyperuricemia

Postmarketing reports: Blood glucose increased, blood uric acid increased[Ref]


Frequency not reported: Conjunctivitis, retinal hemorrhage[Ref]


Frequency not reported: Urticaria

Postmarketing reports: Subcutaneous hemorrhage, pruritus, skin eruptions, Stevens-Johnson syndrome, skin drug eruption, rash[Ref]


Frequency not reported: Anemia

Postmarketing reports: Aplastic anemia, granulocytopenia, pancytopenia, bleeding tendency[Ref]


Frequency not reported: Urinary frequency

Postmarketing reports: Hematuria[Ref]


Frequency not reported: Creatinine increased

Postmarketing reports: BUN increased[Ref]


Frequency not reported: Insomnia[Ref]


Postmarketing reports: Hepatic dysfunction, abnormal liver function tests, jaundice[Ref]


1. Product Information. Pletal (cilostazol). Otsuka American Pharmaceuticals Inc. 2001;PROD.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.