OnePin Peptide Library · Hormonal
ACTH 1-39
ACTH · Corticotropin · Adrenocorticotropic Hormone
ACTH 1-39 is the full 39-amino-acid sequence of adrenocorticotropic hormone (corticotropin), the pituitary peptide that stimulates the adrenal cortex to produce cortisol and other glucocorticoids. The synthetic 1-39 sequence is functionally equivalent to native human ACTH. The shorter cosyntropin (ACTH 1-24) retains full adrenal-stimulating activity and is the standard diagnostic agent for adrenal function testing (the 'cortrosyn stim test'). H.P. Acthar Gel (porcine ACTH analog, repository corticotropin injection) is FDA-approved for infantile spasms and select autoimmune conditions.
Diagnostic: 0.25mg cosyntropin IM/IV at 8 AM, baseline cortisol drawn before, 30 and 60 min after. Clinical Acthar Gel: per neurology / rheumatology specialist.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
ACTH binds the melanocortin-2 receptor (MC2R) on adrenal cortex cells, primarily in the zona fasciculata. Activation of MC2R via Gs/cAMP/PKA triggers the steroidogenic cascade - cholesterol mobilization, StAR protein upregulation, and downstream P450 enzyme activity producing cortisol, corticosterone, and to a lesser extent aldosterone and adrenal androgens.
Cortisol Production
Primary effect. Plasma cortisol rises within 30-60 minutes of ACTH administration; baseline cortisol restored over 4-8 hours.
MSH-Like Activity
ACTH shares N-terminal sequence with α-MSH and can stimulate MC1R on melanocytes - explains the hyperpigmentation seen in chronic ACTH excess (Addison's disease patients on cortisol replacement, or pituitary ACTH-secreting tumors).
Adrenal Androgens
Modest DHEA stimulation alongside cortisol - relevant in adrenal androgen replacement contexts.
Diagnostic Utility
Acute ACTH stimulation distinguishes primary adrenal insufficiency (failed cortisol response) from secondary adrenal insufficiency (preserved or partial response) - the standard cosyntropin stim test.
Chronic Effects
Sustained ACTH elevation produces Cushing-like syndrome - central obesity, glucose dysregulation, hypertension, muscle wasting, mood changes, immunosuppression. This is why ACTH is not used as a tonic peptide in fitness contexts.
What to expect
Acute cortisol rise within 30-60 min of dose.
Days-weeks of repeated dosing produces glucocorticoid effects.
Chronic dosing produces iatrogenic Cushing syndrome.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Keep separate
Side effects & safety
Commonly reported
- Cortisol elevation (intended for diagnostic use)
- Injection site reaction
Less common & notes
- Iatrogenic Cushing syndrome with chronic dosing - central obesity, hyperglycemia, hypertension, muscle wasting, mood changes, immunosuppression, osteoporosis.
- Hyperpigmentation from MC1R co-activation.
- Suppression of HPA axis upon withdrawal of chronic dosing - can produce adrenal insufficiency.
- Allergic reactions rare.
Pharmacokinetics
Storage. Refrigerate. Reconstituted use within 14 days. Acthar Gel per manufacturer label.
Regulatory status
FDA-approved formulations: H.P. Acthar Gel for infantile spasms and select autoimmune indications, Cortrosyn (cosyntropin 1-24) for diagnostic adrenal testing. Synthetic ACTH 1-39 as a research chemical is not appropriate for community use. WADA prohibited.
Put it to work
Calculate, log & track
Open ACTH 1-39 straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open ACTH 1-39 in the app →Go deeper
The guide & community
The complete ACTH 1-39 walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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