Meldonium is probably one of the best-known doping substances, especially in Russia and Eastern Europe — even people who have never run have heard of it. Under the brand name Mildronate it was prescribed for decades for cardiac ischaemia, and in 2016 hundreds of athletes were caught with it. Ten years on, the questions “does it actually work?” and “can you test positive by accident?” are still among the most common. In 2026, a detailed review of the evidence and two studies on accidental meldonium intake were published. Let's see what they show.

What this substance is

Meldonium was created in 1974 by Ivars Kalviņš at the Latvian Institute of Organic Synthesis — originally to speed up growth and boost fertility in farm animals. Later it came to be used in cardiology. The European Medicines Agency has never approved it: the drug is registered mainly in former Soviet countries, including Latvia, where it is produced.

The mechanism works like this: meldonium inhibits carnitine synthesis — carnitine being the molecule that carries fatty acids into the mitochondria. The cell burns less fat and more glucose. When oxygen is in short supply (ischaemia), this is an advantage: on glucose, each molecule of oxygen yields slightly more energy. That is why Western literature calls meldonium a “metabolic modulator”, while Eastern literature calls it an “antihypoxant”. For more on carnitine itself, see our article on L-carnitine and fat burning.

Why it was banned

The decisive data came from the 2015 European Games in Baku (Stuart and colleagues, British Journal of Sports Medicine, 2016):

meldonium was found in 66 of 762 samples — 8.7%;
it was present in athletes from 15 of 21 sports;
yet only 23 of 662 athletes (3.5%) declared it themselves on their doping control forms, among them 13 winners.

From 1 January 2016, WADA added meldonium to the Prohibited List (class S4, “hormone and metabolic modulators”), and it is prohibited at all times — both in and out of competition. An important detail the Swedish authors highlight: WADA's wording referred to “evidence of its use by athletes with the intention of enhancing performance”, not to a proven effect.

The ban was followed by an explosion of violations. According to WADA data compiled by Malm and Svensson, there were 515 positive tests in 2016, 79 in 2017, 111 in 2018, and then 63–79 a year (except in the pandemic year of 2020, when there were 26); in 2024 there were 63. Almost every year, meldonium ranked first or second in its class, S4.

Is there evidence of benefit

The review by Malm and Svensson of Umeå University (Sweden; Frontiers in Sports and Active Living, June 2026) gives a short answer: there is no high-quality evidence.

“Endurance” effects have been shown mainly in animals, for example in rats in a forced swim test. The authors regard extrapolating them to voluntary running in humans as speculation.
The only placebo-controlled study in healthy athletes is a Russian paper by Goloborodko and Razinkin (2021). 20 elite biathletes and cross-country skiers (10 men and 10 women, around 20 years old) received Mildronate or placebo for 15 days.
The groups were allocated not randomly but on the basis of test results. As a result, the Mildronate group had a baseline VO₂max of about 66 and the placebo group about 56 mL/kg/min. Groups like these cannot be compared properly.
Even so, according to the paper itself, by day 15 the Mildronate group showed a decrease in VO₂max, VO₂ at the anaerobic threshold and maximal workload. Their mood index fell, while in the placebo group it rose.

The review's authors add a physiological argument. If meldonium suppresses fat burning and boosts glucose breakdown, then exercise should produce more lactate, and glycogen stores should run down faster. For a marathon or an ultra, where sparing glycogen is exactly what decides the outcome, this is more likely a drawback. This is a hypothesis, not a measurement: the skier study did not directly compare lactate or glycogen.

Can meldonium get into your body by accident

It can — and this is no longer just theory. The Moscow anti-doping laboratory (Postnikov and Efimova, Drug Testing and Analysis, 2026) studied the veterinary drug Emidonol. In the animal's body it breaks down into meldonium and emoxypine.

Meat. Calves were slaughtered 15 and 30 days after a 15-day course. The mean meldonium concentration in raw meat reached 5250 ng/g on day 15 and 3110 ng/g on day 30. Frying and baking reduced the concentration but did not remove it. After a single portion of cooked meat (350 g), meldonium was detectable in urine for 24–28 hours, and in the first 2–14 hours the concentration could exceed the level that anti-doping laboratories are required to be able to detect (WADA's MRPL). In other words, such a sample could have come back positive.
Milk (a separate study by the same laboratory). Three volunteers each drank 900 mL of unpasteurised milk from a cow on the last day of its course. Meldonium in urine peaked at 322 ng/mL after 6–9 hours, and elimination took 35–45 hours.

The authors propose emoxypine as a possible marker: if a sample contains both meldonium and emoxypine, this may point to contaminated food rather than tablets. But the marker is not perfect: emoxypine is itself a common medicine in Russia (Mexidol), and the data are still preliminary.

Limitations

The Swedish authors' review is narrative, not a systematic review with a meta-analysis.
The skier study — 20 people, 15 days, no randomisation; it proves neither benefit nor harm.
The meat and milk studies are pilot studies: 3 animals per time point and 3 volunteers.
The long-term safety of meldonium in healthy trained people has not been studied.

How to apply this

If you are subject to doping control — meldonium is prohibited at all times. It is eliminated slowly, so stopping “a week before the race” won't work.
If you are an amateur without doping control — there is no evidence that meldonium improves endurance in a healthy person. And cutting down fat metabolism is a dubious idea for long distances.
This is a prescription heart medication. Don't prescribe it to yourself “for sport” without a doctor. If it has been prescribed to you for medical reasons and you compete in events with doping control, discuss alternatives or a therapeutic use exemption with your doctor.
Be careful with farm meat and milk before a race with doping control if you don't know what the animals were treated with.
For comparison: with EPO, unlike meldonium, a rise in VO₂max has been confirmed in a randomised trial — see our look at EPO in the marathon.

The bottom line

At Baku 2015, meldonium was found in 8.7% of samples across 15 of 21 sports; WADA has banned it since 2016.
In 2016 alone there were 515 positive tests; almost ten years later there are still 60–80 a year.
There is no high-quality evidence of benefit for athletes. In the only placebo-controlled (but not randomised) study, VO₂max in skiers did not rise but fell.
Meldonium can get into a sample from the meat and milk of animals treated with Emidonol; emoxypine in urine may point to such a source.

Sources: Malm C., Svensson M. “Meldonium and human sport performance: a narrative review evaluating the evidence for ergogenic potential”. Frontiers in Sports and Active Living, 2026;8:1822778. DOI: 10.3389/fspor.2026.1822778 · Stuart M., Schneider C., Steinbach K. “Meldonium use by athletes at the Baku 2015 European Games”. British Journal of Sports Medicine, 2016;50(11):694-698. DOI: 10.1136/bjsports-2015-095906 · Postnikov P.V., Efimova Y.A. “HILIC-MS/MS Detection of Meldonium in Meat from Emidonol-Treated Calves and Volunteer Urine After Consumption: An Anti-Doping Perspective”. Drug Testing and Analysis, 2026;18(9):1198-1202. DOI: 10.1002/dta.70111 · Postnikov P.V., Efimova Y.A., Rodin I.A. “Emoxypine as a Potential Marker for Identifying Possible Cases of Unintended Meldonium Doping in Sports”. Drug Testing and Analysis, 2026;18(3):414-418. DOI: 10.1002/dta.70031