Using tadalafil as a 'pre-workout' in gyms can bring risks

The medicine, used to treat erectile dysfunction, is gaining popularity among gym-goers as a type of "pre-workout", according to experts interviewed by the report.

The perception is accompanied by the number of publications on social networks, which disseminate the off-label practice (when a medicine is used for a purpose other than that approved in the leaflet).

The logic seems to make sense. Upon reaching the stomach, the medicine enters the bloodstream and inhibits the enzyme PDE-5 (phosphodiesterase), which controls the tone of blood vessels. Without this enzyme getting in the way, the arteries relax and blood flow to the muscles increases. During training, the sensation is of more swollen arms, the famous pump (meaning "to pump" in English).

The problem is that this hypothesis is not supported by available scientific evidence and can expose users to risks ranging from drops in pressure to muscle injuries.

Cardiologist Fernando Costa, coordinator of the ICU at Hospital Santa Paula, part of Rede Américas, says he has noticed an increase in use among patients, especially younger ones, who seek him out for check-ups. "In general, they are healthy individuals."

The consumption of tadalafil, in fact, has grown in recent years in Brazil. Data from Anvisa (National Health Surveillance Agency) show that 74.9 million boxes of the medicine were sold in 2025, 15.8% more than in 2024, when the total was 64.7 million. In 2015, sales totaled 3.2 million units.

Although tadalafil is considered safe when prescribed for specific indications, such as urinary symptoms related to benign prostatic hyperplasia, and under medical supervision, experts consulted by Folha state that there is no proof that it increases strength, muscular hypertrophy or physical performance in healthy people.

"Studies on healthy athletes have shown that tadalafil does not improve physical fitness parameters. One study even demonstrated an increase in markers of muscle damage. The pump is just a temporary sensation, not an indicator of hypertrophy or strength gain", says endocrinologist Pedro Guilherme Cabral, from Hospital Brasília.

If the expected benefits are not supported by science, the risks associated with the indiscriminate use of tadalafil are known to doctors.

"Tadalafil has systemic vasodilatory properties that can cause transient drops in blood pressure. During high-intensity exercise, especially in hot environments, where there is already peripheral vasodilation and increased cardiovascular demand, this can result in dizziness, hypotension and even syncope [fainting]", says Cabral.

Cabral says that the medicine is contraindicated for people with a recent heart attack, recent stroke, unstable angina and severe heart failure.

According to Costa, healthy people rarely experience serious events related to the medication, but some symptoms require attention, especially when they appear during or shortly after physical activity.

The main warning signs include chest pain, intense dizziness, fainting or a feeling of imminent fainting, which may indicate a significant drop in blood pressure.

"Patients who experience chest pain after taking tadalafil should seek immediate medical attention," says Costa.

Another condition that requires emergency care is priapism, an erection that persists for more than four hours, whether painful or not. The episode can cause permanent damage if not treated quickly.

"In the absence of evidence of benefit for sports performance or muscle mass gain, what remains is only exposure to unnecessary risks", says Cabral.

He recommends that anyone looking to increase muscle mass focus their efforts on strategies already consolidated by sports medicine. "The true pillars for mass gain and performance are adequate training, balanced nutrition, adequate rest and patience. There are no safe shortcuts."

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