Tetracosactide (synthetic ACTH, Synacthen)
Tetracosactrin, Cosyntropin, ACTH 1-24, Synacthen Depot, Cortrosyn, Corticotropin, Corticotropin (ACTH 1-39), Acthar
Forms: Short-acting injection used for the adrenal function test (Synacthen, cosyntropin/Cortrosyn) and slow-release Synacthen Depot. Natural-source corticotropin (Acthar Gel, from porcine pituitary) is covered here too.
Synthetic fragment of ACTH (the first 24 of its 39 amino acids) that makes the adrenal glands release cortisol. Not a glucocorticoid itself, but prolonged use can cause cortisol excess.
Legal status: Prescription medicine; varies by country. WADA S2 (corticotrophins): prohibited at all times, in and out of competition.
What it gives
What people use it for and what the sources report. Strength is a general category from the literature: mild, clear or strong.
Purpose
Used as a doping agent to raise the body's own cortisol, in the hope of more energy, less fatigue and faster recovery; the IOC banned ACTH in 1989. Medical use: diagnosing adrenal insufficiency; corticotropin gel for infantile spasms and multiple sclerosis relapses.
What people seek and what studies show
Sought effects: more energy, less fatigue, an anti-inflammatory effect through higher cortisol. A placebo-controlled study found none: in 8 trained cyclists a single injection did not change 20-km time-trial performance or perceived exertion, on the day or the day after. Effects of repeated use were not studied.
Effects
No clear training effect in the sources.
Evidence: Approved medicine — studied in people for its medical use
Possible side effects
Possible does not mean certain: whether they appear depends on dose, duration, individual response and monitoring. Below — what to watch for and how to notice it early.
7 possible side effects
level · how often it is reportedWhat the levels mean
Level: general category from the literature, not your personal risk
How often
- common
- reported often
- possible
- reported in some people
- rare
- reported occasionally
How to lower the risks
For 4 of 7 possible side effects there are specific ways to lower the chance: everyday measures, supplements and options a doctor may consider. For the rest — general advice. No measure removes a risk completely.
After more than a few weeks of use, never stop abruptly: a doctor plans a gradual taper and may check morning cortisol. Tell any doctor treating you, especially before surgery or with a serious illness.
Strength and weight-bearing training, enough calcium and vitamin D from food, no smoking; with long-term use a doctor may order a bone density scan.
How each option helps (1)
- Calcium — With vitamin D it lowered stress fractures in female recruits; in older adults, supplement trials show weak and inconsistent effects on fractures.
Sterile technique, never share needles, vials or pens; see a doctor for a hot, swollen site. If equipment was ever shared, test for HIV and hepatitis B/C and ask about hepatitis B vaccination.
More daily movement, fewer fast carbs, check fasting glucose and HbA1c.
How each option helps (7)
- Glucose monitoring — Rising fasting readings reveal insulin resistance from GH or other drugs early.
- Regular blood tests — Fasting glucose, insulin and HbA1c catch rising blood sugar early — key with GH, its secretagogues and insulin.
- Regular cardio training — Improves insulin sensitivity — useful against the blood-sugar rise from GH and its secretagogues.
- Working with a doctor — Interprets glucose markers and treats early metabolic problems.
- Berberine — Meta-analyses: lower fasting glucose and HbA1c (about 0.6% in type 2 diabetes); smaller effect when glucose is normal.
- Alpha-lipoic acid — Small drops in fasting glucose, insulin and HbA1c in meta-analyses; no real counter to GH- or insulin-driven resistance.
- Psyllium husk fiber — Slows sugar absorption: lower fasting glucose and HbA1c, mostly in people with diabetes.
Less salt, regular cardio, good sleep; home readings; a doctor if it stays high.
How each option helps (8)
- Home blood-pressure monitoring — Seated, rested readings on several days show your true BP; persistently high values are a signal to see a doctor.
- Regular cardio training — Regular aerobic training lowers resting BP by a few mmHg, more in people with high BP.
- Working with a doctor — Diagnoses persistent hypertension and prescribes treatment when needed.
- Avoiding alcohol and other liver stressors — Regular drinking raises blood pressure; cutting it out lowers it.
- Coenzyme Q10 — Inconsistent: some analyses show a small systolic drop in cardiometabolic disease, but a Cochrane review found no clinically meaningful effect.
- Magnesium — Meta-analysis of trials: about 2 mmHg lower systolic pressure on average.
- Omega-3 (fish oil, EPA/DHA) — Small drop of a few mmHg, mainly in people with untreated high blood pressure.
- Taurine — Meta-analysis of 20 small trials: about 4 mmHg lower systolic pressure on average.
Hand hygiene, vaccinations kept up to date (ask a doctor), and seeing a doctor early with fever or a wound that gets worse.
Sleep routine, no stimulants late in the day, magnesium or melatonin.
How each option helps (5)
- Sleep hygiene — A steady routine and no late caffeine ease stimulant- and steroid-related insomnia; night sweats on trenbolone persist regardless.
- Glycine — Small trials show slightly better sleep quality and less next-day fatigue; not a sedative and not for anxiety.
- L-theanine — Small gain in subjective sleep quality; effects on anxiety are inconsistent. May smooth caffeine jitters but won't offset strong stimulants like clenbuterol.
- Magnesium — Three small, low-quality trials in older adults: falling asleep about 17 minutes sooner. No good data in athletes.
- Melatonin — Helps you fall asleep a little faster, especially with a shifted body clock; does not treat anxiety or night sweats.
Check-ups and blood tests
Which tests and check-ups to do and when. This is a guide — agree the exact schedule with your doctor.
Which doctors can help
At home
- Home blood pressure: 2–3 times a week in the morning, keep a log
Get medical help at once if
- After stopping or missing it: severe weakness, vomiting, belly pain, dizziness or fainting, confusion — this can be an adrenal crisis; seek urgent care.
- Sudden severe headache, vision changes, numbness or weakness on one side, trouble speaking — call emergency services.
- Fever with chills, fast breathing, confusion, or redness that spreads quickly — seek urgent care.
- A hot, red, swollen or pus-filled injection site with fever — signs of an abscess; see a doctor.
In an emergency, call your local emergency number.
For women
The corticotropin label warns it may cause fetal harm in pregnancy and lists menstrual irregularities. Use while breastfeeding needs a doctor's decision.
Myth & fact
“Synacthen boosts performance because it raises your own cortisol.”
In a placebo-controlled study in trained cyclists, it raised hormone levels but did not change time-trial results or perceived exertion.
Combinations
No specific combination notes for this substance yet. The stack check still adds up side effects that several substances share.
Sources
Possible side effects by body system, combinations, how to lower the risks and which tests to do — free.
Open the stack check