Yes. 7 FDA-approved labels for Spironolactone carry a boxed warning, and its subject is spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats. 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 Spironolactone warning opens on one specific label, identified underneath it. All 7 Spironolactone labels sampled carried this same wording, which is unusual: most drugs show several.
WARNING Spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats (see PRECAUTIONS ). Spironolactone should be used only in those conditions described under INDICATIONS AND USAGE . Unnecessary use of this drug should be avoided.
SPIRONOLACTONE, Aphena Pharma Solutions - Tennessee, LLC, label version effective 14 October 2021. read the full label on DailyMed.Why this one is unusually consistent
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, so most drugs carry several different wordings of the same warning. Spironolactone does not: all 7 labels sampled for this page used the wording quoted above, word for word.
That usually means the warning is short and settled, with little room to paraphrase, or that the labels descend from a common source. For a reader it has one practical consequence: unlike most drugs in this section, a Spironolactone refill from a different manufacturer should carry warning text that reads the same as the last one.
Spironolactone is dispensed under 7 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 Spironolactone have a black box warning?
Yes. 7 FDA-approved labels for Spironolactone carry a boxed warning, and its subject is spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats. 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 Spironolactone 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 14 October 2021, the warning concerns spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats. The full text is linked so the exact version can be read rather than summarised.
Does the Spironolactone boxed warning mean the drug is unsafe or being withdrawn?
No. It means the FDA requires the risk of spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats to be communicated prominently so prescribers weigh it explicitly. Spironolactone remains FDA-approved and is dispensed under 7 current labels. A boxed warning is a disclosure requirement, not a judgement that a drug should not be used.
Will a Spironolactone refill from another manufacturer show different warning text?
Probably not, and that makes it unusual. Each manufacturer writes its own label within the FDA's requirements, so most drugs carry several wordings of the same warning. All 7 Spironolactone labels sampled here used identical wording, so the text on a refill should read the same as the last one.
Should I stop taking Spironolactone because of this warning?
This page does not answer that and cannot. The warning about spironolactone has been shown to be a tumorigen in chronic toxicity studies in rats is written for a prescriber deciding whether Spironolactone 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 Spironolactone label, linked below by its DailyMed set identifier so the exact version can be opened rather than taken on trust. The figure of 7 labels, and the count of 1 distinct wordings among 7 sampled, were computed from the openFDA labelling API on 30 August 2026.
- SPIRONOLACTONE prescribing information, Aphena Pharma Solutions - Tennessee, LLC, effective 14 October 2021.
- 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.