Hormones & metabolism ACTH(1-24) analog
Cosyntropin
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- FDA approval
- An FDA-approved product contains this peptide
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
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Key takeaway
Cosyntropin (sold as Cortrosyn) is a synthetic fragment of adrenocorticotropic hormone used as a diagnostic agent to test whether the adrenal glands are working. A dose is given and the resulting rise in cortisol shows how well the adrenals respond. It has long been FDA-approved in the U.S. and is given as a single injection during the test.
At a glance
- What it is
- Synthetic ACTH 1-24, the active portion of adrenocorticotropic hormone
- Approved for
- The ACTH stimulation test for adrenal insufficiency
- Key fact
- The cortisol response after a dose distinguishes normal from inadequate adrenal function
- Route
- Intravenous or intramuscular injection
- Evidence strength
- FDA approved
Summary
Cosyntropin is a synthetic ACTH fragment used to test adrenal function. Learn how the cortisol response is read and what FDA-approved means here.
What is cosyntropin?
Cosyntropin, sold under the brand Cortrosyn, is a synthetic peptide made of the first 24 amino acids of adrenocorticotropic hormone (ACTH). Those 24 amino acids carry the full hormone's ability to stimulate the adrenal glands, so cosyntropin acts like natural ACTH but is simpler to manufacture and standardize. It is used not as a treatment but as a diagnostic agent. It is also known by the generic name tetracosactide. It has been FDA-approved for many years.
How does cosyntropin work?
Cosyntropin binds the melanocortin-2 receptor on the adrenal cortex, the same receptor as natural ACTH, and stimulates the adrenal glands to release cortisol. In the diagnostic test, a baseline cortisol level is measured, a dose of cosyntropin is given, and cortisol is measured again after a set interval. A healthy adrenal gland responds with a clear rise in cortisol; a blunted or absent rise points to adrenal insufficiency.
Because the value of the test lies in the measured response, cosyntropin is given as a single dose under controlled conditions. Studies comparing test protocols have examined lower and standard doses; a meta-analysis found the low-dose test was better than the standard dose at detecting chronic adrenal insufficiency caused by the pituitary or hypothalamus. The test helps distinguish primary adrenal failure from other causes of low cortisol.
Is it FDA-approved?
Editor’s note
Status: Yes. Cosyntropin (Cortrosyn) has long been FDA-approved as a diagnostic agent for screening adrenocortical insufficiency. It is given as a single injection, with cortisol measured before and after.
Category: FDA-approved · Primary body area: Hormones & metabolism
Yes. Cosyntropin (Cortrosyn) has long been FDA-approved as a diagnostic agent for screening adrenocortical insufficiency. It is given as a single injection, with cortisol measured before and after.
What is cosyntropin prescribed for?
Cosyntropin is used for the ACTH stimulation test, to evaluate whether the adrenal glands can produce cortisol normally. It is a diagnostic tool used by clinicians, not an ongoing therapy.
What are the side effects?
According to the prescribing information, reported side effects include:
- Slow or fast heart rate
- High blood pressure
- Swelling in the hands or feet
- Rash
More serious considerations include:
- Allergic reactions, including anaphylaxis
Sources: FDA prescribing information for Cortrosyn; a meta-analysis of corticotropin testing (Kazlauskaite et al., The Journal of Clinical Endocrinology & Metabolism, 2008, DOI: 10.1210/jc.2008-0710), indexed on PubMed. This document is educational and does not constitute medical advice.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
- [2]
approved (PDF)
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