Cilostazol Side Effects

Medically reviewed by Drugs.com. Last updated on Feb 5, 2025.

Applies to cilostazol: oral tablet.

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.

It may take several weeks for this medicine to work. If you feel that this medicine is not working, do not stop taking it on your own. Instead, check with your doctor.

Cilostazol can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects, such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

Contact your doctor right away if you have any changes to your heart rhythm. You might have a fast, pounding, or irregular heartbeat or pulse, fainting, or palpitations with this medicine.

Dizziness, lightheadedness, or fainting may occur when you get up suddenly from a lying or sitting position. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

Cilostazol may cause heart problems. Check with your doctor right away if you have chest pain or tightness, decreased urine output, dilated neck veins, extreme fatigue, irregular heartbeat, swelling of the face, fingers, feet, or lower legs, troubled breathing, or weight gain.

Smoking tobacco products, such as cigarettes, may worsen your condition. It contains nicotine which may further narrow blood vessels and may also affect how this medicine works. Therefore, it is best to avoid smoking.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

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:

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

Symptoms of overdose

• dizziness or lightheadedness when getting up suddenly from a lying or sitting position

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:

Less common

• bone pain
• burning feeling in the throat or chest
• difficulty with swallowing
• hives
• pain or stiffness in the joints
• ringing or buzzing in the ears
• swelling of the face, fingers, or lower legs

See also:

For healthcare professionals

Applies to cilostazol: oral tablet.

General adverse events

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

Gastrointestinal

• 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]

Immunologic

• Very common (10% or more): Infection (up to 14%)
• Postmarketing reports: Anaphylaxis, angioedema, hypersensitivity^[Ref]

Respiratory

• Very common (10% or more): Rhinitis (up to 12%), pharyngitis (up to 10%)
• Frequency not reported: Epistaxis
• Postmarketing reports: Pulmonary hemorrhage, interstitial pneumonia^[Ref]

Cardiovascular

• 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]

Other

• Common (1% to 10%): Peripheral edema
• Frequency not reported: Fever, generalized edema, malaise
• Postmarketing reports: Pain, chest pain^[Ref]

Metabolic

• Frequency not reported: Anorexia, hyperuricemia
• Postmarketing reports: Blood glucose increased, blood uric acid increased^[Ref]

Ocular

• Frequency not reported: Conjunctivitis, retinal hemorrhage^[Ref]

Dermatologic

• Frequency not reported: Urticaria
• Postmarketing reports: Subcutaneous hemorrhage, pruritus, skin eruptions, Stevens-Johnson syndrome, skin drug eruption, rash^[Ref]

Hematologic

• Frequency not reported: Anemia
• Postmarketing reports: Aplastic anemia, granulocytopenia, pancytopenia, bleeding tendency^[Ref]

Genitourinary

• Frequency not reported: Urinary frequency
• Postmarketing reports: Hematuria^[Ref]

Renal

• Frequency not reported: Creatinine increased
• Postmarketing reports: BUN increased^[Ref]

Psychiatric

• Frequency not reported: Insomnia^[Ref]

Hepatic

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

Further information

Cilostazol side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer