Guide to Glucocorticoids: Performance, Risks, and WADA Rules

 

Glucocorticoids aren't used to build muscle like anabolic steroids. Instead, they can provide a short-term, performance-altering advantage by:

Masking pain and inflammation: They can quickly reduce swelling and pain from an injury, allowing an athlete to train or compete when they otherwise couldn't. This can be dangerous, as it pushes the body beyond its safe limits and risks further injury.

Creating a sense of well-being: High doses can produce a temporary feeling of euphoria or increased energy, which may be perceived as a performance boost.

Improving respiratory function: While inhaled glucocorticoids are legitimately used for asthma, some athletes may abuse them at higher-than-therapeutic doses to gain an unfair advantage in endurance sports.

Despite these perceived benefits, chronic or high-dose use of glucocorticoids can cause serious health problems, including muscle wasting, bone demineralization, insulin resistance, and suppressed immunity.

 

The World Anti-Doping Agency (WADA) prohibits most systemic glucocorticoids—those taken orally, intravenously, or intramuscularly—in-competition. The ban is in place because these drugs offer an unfair performance advantage and pose significant health risks to athletes. Athletes with a legitimate medical need for glucocorticoids must obtain a Therapeutic Use Exemption (TUE) and follow strict rules regarding dosage and "wash-out" periods before competing.

 

Given the significant health risks, researchers are exploring ways to counteract some of the harmful side effects of glucocorticoid use. A promising 2025 randomized, double-blind, placebo-controlled crossover trial led by Susanne Thierry et al. investigated whether metformin, a common diabetes drug, could help.

 

The study involved 18 healthy men who received a high dose of prednisolone (30 mg/day) for seven days, along with either metformin or a placebo. The findings were encouraging: metformin appeared to blunt the rise in insulin resistance and reduce markers of protein breakdown and bone resorption. This suggests that metformin may offer partial protection for muscle and bone metabolism during short-term glucocorticoid exposure.

 

While the findings on metformin are promising, they come with significant limitations. The study was short, involved only healthy young men, and did not examine all of the side effects of glucocorticoids. Most importantly, metformin does not prevent adrenal suppression, immune system effects, or other serious harms.

 

The most crucial takeaway for athletes is this: using metformin does not make doping safe or legal. Combining it with a banned substance does not change the regulatory status of that substance.

 

For athletes, the safest and only legitimate path is to use glucocorticoids strictly under medical supervision for a valid health condition. If the medication is on the WADA Prohibited List, a TUE must be obtained to ensure compliance and prioritize health and fair play.

 

Below are some of the widely available glucocorticoids with typical medical doses for adults. These numbers are for legitimate therapy; they do not represent doping doses, which can be unsafe.

Prednisone / Prednisolone: Common brand examples include Deltacortril and Prednisolone. A typical adult oral dose is 5–60 mg per day, often in split doses depending on the condition. This is a standard medium-potency oral glucocorticoid.

Methylprednisolone: Common brand examples include Medrol and Solu-Medrol. The typical oral dose is 4–48 mg per day, with high-dose intravenous (IV) pulses used for severe flares. It is slightly stronger than prednisolone.

Dexamethasone: Common brand examples include Decadron and Dexamethasone. The typical oral dose is 0.5–10 mg per day. It is very long-acting and about 25 times more potent than natural cortisol.

Triamcinolone: Common brand examples include Kenacort and Nasacort (inhaled). Oral use is rare. It is typically injected at 10–40 mg per joint or inhaled at 55–220 µg twice daily for allergies and asthma.

Betamethasone: A common brand example is Celestone. The typical oral dose is 0.6–7 mg per day. It is very potent and long-acting, often used in topical or injectable forms.

Hydrocortisone: A common brand example is Cortef. The typical oral dose is 15–240 mg per day, usually divided into two or three doses. It is the closest synthetic drug to natural cortisol.

 

*Doses vary by disease severity, route, and patient factors. Short "bursts" may be higher for a few days. Long-term therapy aims for the lowest effective dose.

 

Other forms include inhaled glucocorticoids (budesonide, fluticasone, mometasone) for asthma/COPD and topical creams for skin conditions. Systemic (oral, IV, IM) glucocorticoids are the main focus of WADA’s ban in-competition because they exert full-body effects.