BIOHACKPHARMStack Analyzer

Methoxy polyethylene glycol-epoetin beta (CERA, Mircera)

C.E.R.A., EPO CERA, Continuous erythropoietin receptor activator, PEG-epoetin beta

EPO & blood boostersPrescription onlyWADA S2 · prohibitedEvidence: approved medicineExtreme risk

A third-generation erythropoietin: epoetin beta bound to a large polyethylene glycol chain, so its half-life is about five days. Approved for anemia of kidney disease; misused in endurance sport.

Legal status: Prescription medicine for anemia of kidney disease; rules vary by country. Banned in sport at all times (WADA S2.1.1, named as CERA).

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

Medically: anemia from chronic kidney disease only; not recommended for chemotherapy anemia after a trial with more deaths. In sport: endurance blood doping; riders tested positive for it during and after the 2008 Tour de France. There is no safe way to use it in a healthy person.

What people seek and what studies show

Used for endurance by raising red cells and hemoglobin. Its effect on performance has not been studied in athletes; the expectation comes from other erythropoietins, where lab endurance rose but a race result in trained cyclists did not. Its long half-life means it keeps acting long after the last injection.

Effects

Endurance

Evidence: Approved medicine — studied in people for its medical use

Possible side effects

With an extreme-risk substance some of these can be life-threatening or permanent; no dose, test or early sign makes it safe. Below — what each risk looks like; the signs that need urgent help are in block 04.

7 possible side effects

level · how often it is reported
High
Thick blood (hematocrit) / clot risk
Excess red cells thicken the blood and raise the risk of clots, stroke and heart attack, and the long action keeps the rise going. No measure makes use in a healthy person safe.
How to notice: Often silent; sometimes headaches, flushed face, itch after a hot shower.
common
High
Heart strain / heart-muscle thickening
In kidney patients, higher hemoglobin targets with ESAs increased deaths, heart attacks, strokes and heart failure; no target or dose free of this risk has been found.
How to notice: Shortness of breath on effort, lower endurance, palpitations.
possible
Elevated
Higher blood pressure
About 27% of kidney patients needed stronger blood-pressure treatment; hypertensive encephalopathy and seizures have occurred, and severe hypertension after overdose.
How to notice: Often silent; sometimes headaches, flushing, nosebleeds — a home monitor shows it.
possible
Elevated
Black-market quality risk (fakes, contamination)
When it is obtained outside pharmacies, the identity, potency, storage and sterility of this protein drug cannot be checked.
How to notice: Unexpected effects, pain or infection, a stronger or weaker effect than expected.
possible
Moderate
Unknown long-term safety (little human data)
Not studied in healthy athletes. Antibodies against erythropoietin that switch off own red-cell production (pure red-cell aplasia) have been reported with it.
How to notice: Nothing to notice — the risk is what is not yet known.
possible
Moderate
Abnormal tissue growth (theoretical cancer risk)
ESAs shortened survival or sped tumor growth in several cancers, and a Mircera trial in lung cancer stopped early with more deaths than another ESA; relevance to healthy people is unknown.
How to notice: No direct signs — the point is not to fuel existing growths.
rare
Low
Injection pain, infection, oil cough
Local pain or irritation; shared or non-sterile equipment carries a risk of infection.
How to notice: Soreness, lumps; a short coughing fit right after an injection.
possible

How to lower the risks

Extreme risk

Extreme risk. No measure makes using this substance for sport safe: severe, including life-threatening, consequences are possible. The only reliable way to avoid these risks is not to use it.

If a doctor prescribed this medicine to treat you, do not stop taking it on your own — discuss it with your doctor.

Warning signs that need urgent help are listed in block 04.

Check-ups and blood tests

For an extreme-risk substance there is no testing schedule.

No testing schedule makes this substance safe, so there is no plan of tests here. If it has already been taken, watch for the urgent warning signs on this page and see a doctor — tell them exactly what was taken.

Get medical help at once if

  • Swelling, pain or redness in one leg; sudden shortness of breath or chest pain; sudden one-sided weakness or numbness, trouble speaking or seeing — seek urgent care.
  • Chest pain or pressure, breathlessness on light effort, swollen ankles, fainting — seek urgent care.
  • Sudden severe headache, vision changes, numbness or weakness on one side, trouble speaking — call emergency services.
  • A new lump (including in the neck), trouble swallowing or persistent hoarseness, unexplained weight loss, or blood in stool or urine — see a doctor promptly.

In an emergency, call your local emergency number.

For women

Pregnancy data are insufficient; in animal studies, offspring were harmed at doses far above the human dose.

Myth & fact

Myth

“Long-acting CERA is smoother and safer than ordinary EPO.”

Fact

It carries the same boxed warning for death, heart attack, stroke and clots, and because it stays in the body for days, it keeps acting long after the last injection.

Combinations

No specific combination notes for this substance yet. The stack check still adds up side effects that several substances share.

Sources

FDA: Mircera (methoxy polyethylene glycol-epoetin beta) prescribing information (opens in a new tab)Rocca et al., Drug Test Anal 2021: CERA misuse for doping in endurance sports has been reported (opens in a new tab)Heuberger et al., Br J Clin Pharmacol 2013: erythropoietin doping in cycling — lack of evidence for efficacy, negative risk-benefit (opens in a new tab)