Does Pletal (cilostazol) cause side effects?

Pletal (cilostazol) is a quinolinone derivative used to treat intermittent claudication, a condition caused by narrowing of the arteries that supply the legs with blood. 

Patients with intermittent claudication develop pain when they walk because not enough oxygen-containing blood reaches the active leg muscles. Pletal reduces the pain of intermittent claudication by dilating the arteries, thereby improving the flow of blood and oxygen to the legs. (It does this by decreasing the action of an enzyme, phosphodiesterase III.) It also reduces the ability of blood to clot.

Pletal enables patients with intermittent claudication to walk longer and faster before developing pain. 

Common side effects of Pletal include

Serious side effects of Pletal include

  • reduced numbers of white blood cells and platelets and
  • severe skin reactions.

Drug interactions of Pletal include erythromycin, omeprazole, and diltiazem, which increase the concentration of Pletal by blocking the action of enzymes that destroy Pletal.

  • Though not specifically studied, a similar interaction could occur with ketoconazole, itraconazole, fluconazole, miconazole, fluvoxamine, fluoxetine, nefazodone, and sertraline.
  • Diltiazem and omeprazole also increase concentrations of Pletal. Higher concentrations of Pletal could increase the possibility of toxic effects. Therefore, a dose of 50 mg twice daily should be considered when drugs that may increase the concentration of Pletal also are being used.
  • Combining Pletal with other drugs that interfere with the blood clotting process may increase the likelihood of bleeding. A high fat meal increases the absorption of Pletal.
  • Grapefruit juice could increase the concentration of Pletal and should not be taken by patients on Pletal. 

The use of Pletal in pregnancy has not been adequately studied. Pletal has not been adequately studied in women who are breastfeeding. Consult your doctor before breastfeeding.

What are the important side effects of Pletal (cilostazol)?

The most common adverse effects of cilostazol are:

Other important side effects which have also been reported with cilostazol include a reduction in numbers of white blood cells and platelets. Severe skin reactions also have been reported.

Cilostazol inhibits the enzyme phosphodiesterase III. Other drugs that inhibit this enzyme have caused death in individuals with heart failure. Therefore, individuals with heart failure should not use cilostazol.

Pletal (cilostazol) side effects list for healthcare professionals

The following adverse reactions are discussed in greater detail in other sections of the labeling:

Clinical Trials Experience

  • Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
  • Adverse reactions were assessed in eight placebo-controlled clinical trials involving patients exposed to either 50 or 100 mg twice daily Pletal (n=1301) or placebo (n=973), with a median treatment duration of 127 days for patients on Pletal and 134 days for patients on placebo.
  • The most frequent adverse reaction resulting in discontinuation of therapy in more than 3% of patients treated with Pletal was headache [50 mg twice daily (1.3%), 100 mg twice daily (3.5%) and placebo (0.3%)].
  • Other frequent causes of discontinuation included palpitation and diarrhea, both 1.1% for Pletal (all doses) versus 0.1% for placebo.
  • The most common adverse reactions, occurring in at least 2% of patients treated with Pletal 50 or 100 mg twice daily, are shown in Table 1.

Table 1: Most Common Adverse Reactions in Patients on Pletal (PLT) 50 or 100 mg Twice Daily(Incidence at least 2% and Occurring More Frequently (≥ 2%) in the 100 mg Twice Daily Group than on Placebo)

Adverse ReactionsPlacebo
PLT 50 mg twice daily
PLT 100 mg twice daily
Abnormal stools4%12%15%
Peripheral edema4%9%7%
Abdominal pain3%4%5%

Less frequent clinical significant adverse reactions (less than 2%) that were experienced by patients treated with Pletal 50 mg twice daily or 100 mg twice daily in the eight controlled clinical trials and that occurred at a frequency in the 100 mg twice daily group greater than in the placebo group are listed below.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Pletal. Because these reactions are reported voluntarily from a population of an unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Blood And Lymphatic System Disorders
Cardiac Disorders
  • Torsade de pointes and QTc prolongation in patients with cardiac disorders (e.g. complete atrioventricular block, heart failure; and bradyarrythmia),
  • angina pectoris.
Gastrointestinal Disorders
General Disorders And Administration Site Conditions
Hepatobiliary Disorders
Immune System Disorders
Nervous System Disorders
Renal And Urinary Disorders
Respiratory, Thoracic And Mediastinal Disorders
Skin And Subcutaneous Tissue Disorders
Vascular Disorders

What drugs interact with Pletal (cilostazol)?

Inhibitors Of CYP3A4 Or CYP2C19

Inhibitors Of CYP3A4
  • Coadministration of strong (e.g., ketoconazole) and moderate (e.g., erythromycin, diltiazem and grapefruit juice) CYP3A4 inhibitors can increase exposure to Pletal.
  • Reduce Pletal dose to 50 mg twice daily when coadministered with strong or moderate inhibitors of CYP3A4.
Inhibitors Of CYP2C19
  • Coadministration with CYP2C19 inhibitors (e.g., omeprazole) increases systemic exposure of Pletal active metabolites.
  • Reduce Pletal dose to 50 mg twice daily when coadministered with strong or moderate inhibitors of CYP2C19.

Treatment & Diagnosis

Medications & Supplements

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Medically Reviewed on 1/4/2021
FDA Prescribing Information

Professional side effects and drug interactions sections courtesy of the U.S. Food and Drug Administration.