Clinicians warn of dangers linked to pre-workout supplements
27 July 2026 | Story Ridovhona Mbulaheni. PhotoUnsplash.
Clinicians from the University of Cape Town (UCT) are warning about potential dangers in pre-workout supplements in a new study.
An adult patient who recently presented to the emergency unit with chest pain, a racing heart and difficulty breathing after consuming a pre-workout supplement and an energy drink has prompted clinicians to call for tighter oversight of a fast-growing but lightly regulated market. Popular among gym-goers and athletes, many of these supplements are sold as proprietary blends that do not fully disclose all their ingredients.
The warning, published in the South African Medical Journal, comes from clinicians in UCT’s Division of Clinical Pharmacology, who are calling for healthcare professionals and consumers to be more aware of the risks associated with multi-ingredient pre-workout supplements (MIPS), products widely marketed to boost exercise performance.
“This case demonstrates the importance of asking patients about supplement use when they present with symptoms of stimulant toxicity. Many people assume these products are safe because they are readily available, yet their ingredients and stimulant content are not always fully disclosed,” said Professor Marc Blockman, director of the World Health Organization Collaborating Centre for Medicines Information at UCT.
The case illustrates how easily consumers may unknowingly ingest potentially harmful amounts of stimulants. The supplements frequently contain methylxanthine stimulants, such as caffeine and theobromine, and international studies have shown that the actual caffeine content in such products can differ substantially from what is stated on the label.
“Stronger regulatory oversight is needed to ensure consumers know what they are taking.”
According to Professor Blockman, caffeine and related methylxanthines stimulate the central nervous system and cardiovascular system. Mild toxicity can cause vomiting, tremors, agitation, rapid breathing and a racing heartbeat, while severe poisoning may lead to abnormal heart rhythms, seizures and muscle breakdown.
He said that there is a significant regulatory gap in South Africa. While injectable caffeine is regulated as a Schedule 3 medicine by the South African Health Products Regulatory Authority, manufacturers may market caffeine-containing pre-workout supplements as food products, placing them outside many of the stringent regulatory requirements that apply to medicines.
Blockman added: “As the use of pre-workout supplements continues to increase, stronger regulatory oversight is needed to ensure consumers know what they are taking and to minimise the risk of avoidable toxicity. Greater transparency around ingredients and stimulant content would help both consumers and healthcare professionals make informed decisions.”
Please view the republishing articles page for more information.
Most read
Prof Thokozani Majozi maps UCT’s next chapter in research11:00, 20 July 2026
Mother tongue-based bilingual education boosts in-class learning09:30, 17 July 2026
UCT student dealt a winning hand in SA bridge14:30, 20 July 2026
‘The future of African science includes me’09:30, 21 July 2026
UCT study finds traces of banned toxic chemicals in children’s products09:30, 8 July 2026
Latest articles
‘Africa’s future lies in agriculture’UCT’s Environmental Humanities South zoomed in on agricultural engineer Amílcar Cabral’s impact on soil science in Africa on the last day of their African Environmentalism of Soil webinar.27 Jul 2026
Clinicians warn of dangers linked to pre-workout supplementsThe case illustrates how easily consumers may unknowingly ingest potentially harmful amounts of stimulants.27 Jul 2026
Professors Dave and Wearne’s real measure of successProfessor Joel Dave and Professor Nicola Wearne delivered their joint inaugural lecture on Thursday, 23 July.27 Jul 2026
Winelands learners win top research prize in IrelandTwo teenagers who are members of the Youth Research Advisory Group linked to the South African Tuberculosis Vaccine Initiative at UCT have won a global accolade.24 Jul 2026
How a Deaf student experienced real inclusion at UCTAs the country celebrated three years since the South African Sign Language was enacted into law, UCT’s Disability Service has upped the ante on making local and international students and staff feel at home.24 Jul 2026
