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Dr. Christos Petrou: GBL is a Substance with Rapid Action and Deadly Risk

Published January 8, 2026, 13:15
Dr. Christos Petrou: GBL is a Substance with Rapid Action and Deadly Risk

Dr. Christos Petrou, Associate Professor at the University of Nicosia, warns of the serious risks to public health posed by the substance GBL (gamma-butyrolactone), which was found in a water cooler in Larnaca and led to the death of a 78-year-old man and the hospitalization of four others. GBL, an industrial solvent, is rapidly converted to GHB in the body, a potent central nervous system depressant. Dr. Petrou explains that GBL has an extremely narrow safety margin and rapid action, with potential effects ranging from drowsiness and nausea to coma, convulsions, and death. The severity of the effects is significantly increased in the elderly due to comorbidities and potential interactions with other medications. He points out that the margin between a safe dose and a toxic dose is very small, and even a small difference in quantity can be critical. Unintentional consumption, such as in the case of contaminated water, dramatically increases the risk, as the person is unaware of the exposure and cannot control the dose. Dr. Petrou emphasizes that GBL is more dangerous than GHB itself due to its faster onset of action. He warns that this substance should not be underestimated and that public awareness is essential to prevent similar tragedies.