UCT Clinicians Warn of Health Dangers from Pre-Workout Supplements After Emergency Case

Following an emergency case where a patient experienced chest pain and a racing heart after consuming a pre-workout supplement and an energy drink, University of Cape Town clinicians are warning of the dangers of multi-ingredient pre-workout supplements. These products often contain methylxanthine stimulants like caffeine and theobromine without full label disclosure. Clinicians are calling for stronger regulatory oversight in South Africa, where these supplements are currently marketed as food products rather than medicines.

Pre-workout supplement emergency case

• ▪An adult patient presented to an emergency unit with chest pain, a racing heart, and difficulty breathing after consuming a pre-workout supplement and an energy drink.
• ▪University of Cape Town clinicians published a study in the South African Medical Journal on July 27, 2026, warning about potential dangers in pre-workout supplements.

Methylxanthine stimulant toxicity risks

• ▪Mild methylxanthine toxicity causes vomiting, tremors, agitation, rapid breathing, and a racing heartbeat, while severe poisoning may lead to abnormal heart rhythms, seizures, and muscle breakdown.
• ▪Pre-workout supplements frequently contain methylxanthine stimulants, such as caffeine and theobromine, which stimulate the central nervous system and cardiovascular system.

Supplement ingredient disclosure gaps

• ▪Many pre-workout supplements are sold as proprietary blends that do not fully disclose all of their ingredients or stimulant content.
• ▪International studies indicate that the actual caffeine content in multi-ingredient pre-workout supplements can differ substantially from what is stated on the product label.

South African regulatory framework

• ▪South African manufacturers may market caffeine-containing pre-workout supplements as food products, placing them outside of stringent medicine regulatory requirements.
• ▪The South African Health Products Regulatory Authority regulates injectable caffeine as a Schedule 3 medicine.

Clinical safety recommendations

• ▪University of Cape Town clinicians recommend that healthcare professionals ask patients about supplement use when presenting with symptoms of stimulant toxicity.
• ▪Professor Marc Blockman called for stronger regulatory oversight of pre-workout supplements to ensure ingredient transparency and minimize the risk of avoidable toxicity.

Consumer awareness needs

• ▪Many consumers assume pre-workout supplements are safe because they are readily available, despite potential risks from undisclosed ingredients.
• ▪University of Cape Town clinicians are calling for healthcare professionals and consumers to be more aware of the risks associated with multi-ingredient pre-workout supplements.

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