Certain devices marketed to disinfect and sanitize continuous positive airway pressure machines may be unsafe, according to the Food and Drug Administration.

Cleaning devices that use ozone gas and UV light are not legally marketed in the United States, the agency reminded users in a recent safety communication. In addition, there may be health risks tied to the gas and light sources involved, said William H. Maisel, M.D., a director in the FDA’s Center for Devices and Radiological Health.

The FDA has received reports citing breathing complaints, headaches and asthma attacks from people who used ozone gas-based products to clean, sanitize or disinfect CPAP devices and accessories. Investigators also found ozone levels above limits considered safe for human exposure in some devices. While the agency has not received complaints about devices that use UV light, these products could cause burns, eye damage or increase the risk of skin cancer, Maisel cautioned.

The agency recommends that CPAP users and clinicians follow manufacturers’ cleaning instructions, which typically endorse cleaning with soap and water.

CPAP devices are often prescribed to patients with obstructive sleep apnea. They increase air pressure flow to keep blocked airways open during sleep.