Early Alert: Nitric Oxide Delivery System Issue from NOxBOX

CDRH is issuing this Early Alert to notify the public of a potentially high-risk device issue. The FDA will keep the public informed and update this web page as significant new information becomes available.

Affected Product

The FDA is aware that NOxBOX has issued a letter to affected customers recommending certain nitric oxide delivery systems have updated use instructions.

Affected devices:

Product Name: NOxBOXi Nitric Oxide Delivery System with the NOxMixer module
Unique Device Identifier: 05060541640016
Full List of Affected Serial Numbers

What to Do

These devices are used in critical and emergency situations. Users should review and follow the updated instructions for pre-use inspection. Confirm that the NOxBOXi device functions correctly during its pre-use system checks prior to continued use.

On August 19, NOxBOX sent all affected customers a letter recommending the following actions:

NOxBOXi devices affected by this issue do not need to be removed from service unless the device does not pass the pre-use system checks and setup checks as noted below.
- To avoid leaks at the oxygen inlet of the NOxMixer, ensure the connection between the oxygen supply tubing and the NOxMixer is secure and tight-fitting.
- Complete all NOxBOXi pre-use system checks. Ensure the device functions properly in Emergency or Manual Bagging modes, as described in Chapter 8 of the Technical Guide.
- Check the flowmeter to ensure that the flow indicator ball rises appropriately to an increase in the oxygen flow setting on the NOxMixer control knob.
- Ensure that at least one back-up device is available to allow for quick transition of devices if an oxygen leak is detected within the NOxMixer module of the NOxBOXi device.
Ensure all personnel using the device are provided with a copy of these recommendations and post the firm’s notice near the device.

Check this web page for updates. The FDA is currently reviewing information about this potentially high-risk device issue and will keep the public informed as significant new information becomes available.

How to Identify Affected Products

The images above show the serial number locations for the NOxBOXi delivery system (on the left) and the NOxMixer module (on the right).

Reason for Alert

NOxBOX reported complaints of oxygen leaks due to failure of the oxygen tubing or tubing connection within the NOxMixer module of the NOxBOXi device. This issue only impacts the oxygen tubing or the tubing connection at the elbow fitting upstream of the O2 flowmeter. Different tubing is used downstream of the flowmeter. The downstream tubing is not affected by this issue.

In some cases, oxygen leaks could result in increased dosage of nitric oxide or interruption in therapy. Potential health consequences for an interruption during therapy include oxygen desaturation and increased pulmonary artery pressure with the associated complications. Increased nitric oxide dosages may lead to methemoglobinemia and its associated complications. Neonates with congenital heart disease are at greater risk than other patients for health complications.

NOxBOX stated that it has developed a replacement for the tubing and tubing connection and will be working with distributors to repair all affected devices. Further details will be provided to distributors to ensure all upgrades are successfully completed.

NOxBOX also stated that it is implementing an update to the NOxBOXi + NOxMixer Service Manual to include inspection of the NOxMixer internal oxygen tubing and tubing connection for replacement as part of the preventative maintenance (PM) schedule. Further details will be provided to distributors on these updates once they become available.

As of August 12, 2026, NOxBOX has not reported any serious injuries or deaths associated with this issue.

Device Use

The NOxBOXi Nitric Oxide Delivery System is intended for the delivery and monitoring of a constant concentration of nitric oxide and the monitoring of nitrogen dioxide and oxygen in the inspiratory breathing circuit of a patient undergoing inhaled nitric oxide therapy. The NOxMixer module is intended to deliver a continuous flow of nitric oxide, mixed in line with oxygen for emergency applications and when manually ventilating a patient.

Contact Information

Customers in the U.S. with adverse reactions, quality problems, or questions about this issue should contact NOXBOX at NOxBOX_qatech@linde.com.

Unique Device Identifier (UDI)

The unique device identifier (UDI) helps identify individual medical devices sold in the United States from distribution to use. The UDI allows for more accurate reporting, reviewing, and analyzing of adverse event reports so that devices can be identified more quickly, and as a result, problems potentially resolved more quickly.

How do I report a problem?

Health care professionals and consumers may report adverse reactions or quality problems they experienced using these devices to MedWatch: The FDA Safety Information and Adverse Event Reporting Program.