The study results were published in The Lancet. A total of 298 people with moderate to severe sleep apnea participated in the trial. One quarter of the participants received a placebo, while the rest were treated with different doses of sulthiame. The study took place across four European countries and followed a double blind design, meaning neither the participants nor the researchers knew who was receiving the active drug.

Study Shows Major Reduction in Breathing Pauses

Patients who received higher doses of sulthiame experienced up to 47 percent fewer breathing interruptions during sleep compared with those given a placebo. They also showed improved oxygen levels overnight.

Sulthiame appears to work by stabilizing the body's control of breathing and increasing respiratory drive. This helps lower the likelihood that the upper airway will collapse during sleep, which is the main cause of obstructive sleep apnea. Most side effects reported during the trial were mild and temporary.

Jan Hedner, senior professor of pulmonary medicine at the Sahlgrenska Academy, University of Gothenburg, has played a leading role in the study.

"We have been working on this treatment strategy for a long time, and the results show that sleep apnea can indeed be influenced pharmacologically. It feels like a breakthrough, and we now look forward to larger and longer studies to determine whether the effect is sustained over time and whether the treatment is safe for broader patient groups," says Jan Hedner.

Ludger Grote and Kaj Stenlöf from the University of Gothenburg also made important contributions to the research.

Many Patients Cannot Tolerate CPAP Treatment

Obstructive sleep apnea happens when the upper airway repeatedly collapses during sleep. These episodes cause breathing to stop temporarily, reduce oxygen levels, and repeatedly disrupt sleep. Over time, untreated sleep apnea raises the risk of serious health problems, including high blood pressure, cardiovascular disease, stroke, and type 2 diabetes.

Even though sleep apnea is common, there is currently no medication that directly treats its underlying cause. The most common therapy is continuous positive airway pressure (CPAP), which uses a mask to keep the airway open during sleep. While CPAP is highly effective, many patients find it difficult to use. Up to half stop using the device within a year because the mask can feel uncomfortable or interfere with sleep.

Sulthiame is an existing medication that has previously been approved to treat a form of childhood epilepsy. Researchers are now investigating whether it could also become a drug treatment for sleep apnea.