Meldonium (Mildronate): Endurance Drug That Banned Sharapova
Meldonium reduces fatty acid oxidation in cardiac cells, forcing the heart to use more efficient carbohydrate fuel. Used legally in Eastern Europe as a cardioprotectant — here is the science and sports application.
What Is Meldonium?
Meldonium (INN: Mildronate) was developed in Latvia in the 1970s at the Latvian Institute of Organic Synthesis by Ivars Kalviņš. It is a GBB (gamma-butyrobetaine) analogue that inhibits carnitine biosynthesis and transport. Carnitine is required to shuttle long-chain fatty acids into the mitochondrial matrix for beta-oxidation. By reducing intracellular carnitine levels, Meldonium forces cells — particularly cardiac cells — to use glucose as fuel rather than fat. Glucose is more oxygen-efficient per ATP produced, making it advantageous under ischaemic (oxygen-deficient) conditions and high-intensity exercise.
Cardioprotective Mechanism
During intense exercise or cardiac ischaemia, cells run low on oxygen. Fat oxidation requires more oxygen per unit of ATP than glucose oxidation. By reducing fatty acid oxidation in favour of glucose metabolism, Meldonium makes the heart more efficient under stress. Additionally, it prevents accumulation of cytotoxic acylcarnitine intermediates that form when fatty acid oxidation is incomplete — these intermediates damage cell membranes and impair contractility. This explains its legitimate clinical use in Latvia, Russia, and Eastern European countries for angina, heart failure, and ischaemic heart disease.
Performance Application: Why Athletes Use It
For endurance athletes, the glucose-over-fat shift improves performance at high intensities where oxygen delivery becomes limiting. Athletes (particularly from post-Soviet countries where it was legally available as a supplement) use it to improve VO₂ max, reduce cardiac fatigue, and extend high-intensity output. Maria Sharapova's positive test in 2016 (at doses she stated were for health purposes) brought international attention to the compound. At that point, it had been used by athletes for decades — WADA added it to the prohibited list in January 2016 after its misuse pattern became apparent.
Dosing and Cycle
Typical clinical dose: 500–1,000 mg/day in divided doses, for courses of 4–6 weeks, 2× per year. Athletes report using 500–2,000 mg/day pre-event or during training blocks. It is water-soluble and can be taken orally. No significant hepatotoxicity or endocrine disruption. Primary concern at high doses: conversion to GBB, which via gut bacteria converts to trimethylamine-N-oxide (TMAO) — a compound associated with cardiovascular risk. At standard doses and cycle lengths, clinical safety profile is well-established based on decades of human use.
Legal Status
Meldonium is WADA-banned (S4: Hormone and Metabolic Modulators) in competitive sports. Outside of competition, legal status varies: it is registered as a pharmaceutical drug in Latvia, Lithuania, Russia, Georgia, and several other Eastern European countries. It is not approved by the FDA or EMA. In most Western European countries it is in a grey area: not specifically banned for general sale but not approved as a medicine. Purchasers should verify local regulatory status. WADA detection window: up to 3 months after cessation, which contributed to several athletes claiming inadvertent or discontinued use during 2016 reviews.
Written by
Ivan Kowalski
Exercise Physiologist