FDA-approved
Hormones & metabolism
Corticotropin
Also called ACTH gel
Corticotropin (ACTH) stimulates the adrenal glands and acts on immune cells. Learn what it is, how it works, and its FDA-approved status since 1952.
- Reviewed by
- William Maish, MD MBA MPH, Clinical Product Lead
- Published
- October 5, 2026
- Last updated
- October 5, 2026
Key takeaway
Corticotropin (adrenocorticotropic hormone, or ACTH; sold as Acthar Gel and Purified Cortrophin Gel) is a hormone preparation that stimulates the adrenal glands to make their own steroids and also acts directly on immune cells. It is one of the oldest biologic medicines, used today for conditions ranging from infantile spasms to multiple sclerosis relapses. It has been FDA-approved in the U.S. since 1952 and is given as a long-acting injection.
At a glance
| What it is | A 39-amino-acid adrenocorticotropic hormone (ACTH) preparation in a long-acting gel |
| Approved for | Infantile spasms, acute multiple sclerosis relapses, nephrotic syndrome, and several rheumatic and other inflammatory conditions |
| Key fact | In a controlled study it was more effective than prednisone for stopping infantile spasms |
| Route | Subcutaneous or intramuscular injection |
| Evidence strength | FDA approved |
What is corticotropin?
Corticotropin, better known as adrenocorticotropic hormone (ACTH), is a 39-amino-acid pituitary hormone that drives the adrenal glands to produce cortisol and related steroids. The main product, Acthar Gel (formerly H.P. Acthar Gel), is a purified porcine corticotropin in a long-acting gelatin preparation. A second product, Purified Cortrophin Gel, is also sold. It is one of the oldest biologic drugs, with origins going back to the early 1950s, and it is used in a range of inflammatory and hormonal conditions.
How does corticotropin work?
Corticotropin acts in two ways, summarized in the table below.
| Action | Where it binds | Effect |
| Classic action | Melanocortin-2 receptor on the adrenal cortex | Stimulates the adrenal glands to synthesize and release cortisol, corticosterone, and other steroids, so much of its anti-inflammatory benefit comes indirectly, through the body's own steroid production |
| Direct action | Melanocortin receptors on immune and other cells | Anti-inflammatory and immune-modulating effects that are independent of steroids |
This dual action is part of why it is still used in specific settings rather than being entirely replaced by synthetic steroids. In infantile spasms, a severe infant seizure disorder, a controlled study found high-dose ACTH more effective1 than prednisone for stopping the spasms. Because its downstream effects resemble those of corticosteroids, its side-effect profile does too.
Is it FDA-approved?
Yes. Corticotropin (Acthar Gel) has been FDA-approved2 since 1952, and its infantile spasms indication was formally approved in 2010. Its label covers a broad set of conditions, reflecting both its age and its steroid-like breadth of effect.
What is corticotropin prescribed for?
Corticotropin is prescribed for:
- Infantile spasms in young children
- Acute exacerbations of multiple sclerosis
- Nephrotic syndrome
- Short-term adjunctive therapy in various rheumatic, collagen, dermatologic, allergic, ophthalmic, and other inflammatory conditions, including symptomatic sarcoidosis
Because of its cost and its steroid-like profile, its use is usually reserved for specific situations.
What are the side effects?
According to the prescribing information, common side effects include:
- Injection-site reactions
- Fatigue
- Fluid retention and swelling
- Trouble sleeping and headache
- High blood sugar
In infants treated for infantile spasms, common side effects include:
- Infections
- Convulsions
- High blood pressure
- Irritability
- Fever
More serious considerations include:
- Increased susceptibility to infection from immune suppression
- Adrenal suppression when treatment is stopped
- Growth suppression in children and gastrointestinal bleeding
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Sources: FDA prescribing information for Acthar Gel; a randomized trial of ACTH versus prednisone for infantile spasms (Baram et al., Pediatrics, 1996, PMID: 86042741), indexed on PubMed. This document is educational and does not constitute medical advice.