Yes. 11 FDA-approved labels for Cilostazol carry a boxed warning, and its subject is contraindicated in heart failure patients. A boxed warning is the most serious warning the FDA requires on a prescription label. It is applied to the drug and to the situations in which it is used, not to any particular person taking it.
What the warning says
Below is how the Cilostazol warning opens on one specific label, identified underneath it. Of the 11 Cilostazol labels sampled, 6 carried materially different wordings, and this was the most common, used by 4 of them.
WARNING: CONTRAINDICATED IN HEART FAILURE PATIENTS Cilostazol tablets are contraindicated in patients with heart failure of any severity. Cilostazol and several of its metabolites are inhibitors of phosphodiesterase III. Several drugs with this pharmacologic effect have caused decreased survival compared to placebo in patients with class III-IV heart failure [see Contraindications ( 4 )] . WARNING: CONTRAINDICATED IN HEART FAILURE PATIENTS See full prescribing information for complete boxed warning. Cilostazol tablets is contraindicated in patients with heart failure of any severity. Cilostazol and several of its metabolites are inhibitors of phosphodiesterase III.
CILOSTAZOL, Aphena Pharma Solutions - Tennessee, LLC, label version effective 04 April 2024. Opening of the warning; read the full label on DailyMed.Why the wording differs between manufacturers
There is no single official text of a boxed warning. The FDA sets what a warning must cover, and each manufacturer writes its own label within that. Of the 11 Cilostazol labels sampled for this page, 6 carried materially different wordings of the same warning, and the version quoted above was used by 4 of them.
The hazard does not change between those 6 versions. Only the sentences do, which is why a refill from a different manufacturer can carry warning text that reads differently without anything about Cilostazol or its risks having changed.
Cilostazol is dispensed under 11 current FDA labels despite this warning, which is the point worth holding onto: a boxed warning is a disclosure requirement, not a verdict. What a boxed warning does and does not mean sets out the distinction.
Common questions
Does Cilostazol have a black box warning?
Yes. 11 FDA-approved labels for Cilostazol carry a boxed warning, and its subject is contraindicated in heart failure patients. A boxed warning is the strongest warning the FDA requires on a prescription label, and it is applied to the drug, not to any individual taking it.
What does the Cilostazol boxed warning say?
The wording is set by each manufacturer within FDA requirements, so it varies. In the version quoted on this page, taken from a label effective 04 April 2024, the warning concerns contraindicated in heart failure patients. The full text is linked so the exact version can be read rather than summarised.
Does the Cilostazol boxed warning mean the drug is unsafe or being withdrawn?
No. It means the FDA requires the risk of contraindicated in heart failure patients to be communicated prominently so prescribers weigh it explicitly. Cilostazol remains FDA-approved and is dispensed under 11 current labels. A boxed warning is a disclosure requirement, not a judgement that a drug should not be used.
Why do different pharmacies show different warning text for the same drug?
Because each manufacturer writes its own label within the FDA's requirements. Of 11 Cilostazol labels sampled here, 6 carried materially different wordings of the same warning. The hazard described is the same; the sentences are not. This is a common source of confusion when a prescription is refilled with a different manufacturer's product.
Should I stop taking Cilostazol because of this warning?
This page does not answer that and cannot. The warning about contraindicated in heart failure patients is written for a prescriber deciding whether Cilostazol suits a particular patient, and stopping a prescribed medicine carries its own risks that this page knows nothing about. Raise it with the prescriber or a pharmacist, who can see the whole picture.
Where this page's information comes from
The quotation above is from one Cilostazol label, linked below by its DailyMed set identifier so the exact version can be opened rather than taken on trust. The figure of 11 labels, and the count of 6 distinct wordings among 11 sampled, were computed from the openFDA labelling API on 30 August 2026.
- CILOSTAZOL prescribing information, Aphena Pharma Solutions - Tennessee, LLC, effective 04 April 2024.
- openFDA drug labelling API, the source of the label counts and variant counts on this page.
Labels are revised over time. The version linked above is the one this page was written against, and a newer revision may differ. Counts reflect the labels present in openFDA on the retrieval date.