The U.S Food and Drug Administration announced a recall on Friday of Medtronic’s insulin pump over inconsistent insulin release.

The Class I recall involves Medtronic’s MiniMed Paradigm Insulin Infusion Sets. The company sent an urgent safety warning to doctors and other medical professionals last month about a possible temporary block on the vents of the device if the insulin and other fluids come into contact with its tubing connectors. Once the vents are blocked, the patient may receive either too little or too much insulin which could potentially lead to serious illness or death.

The FDA issues a Class I recall of a product if there is a reasonable chance that it may cause serious illness or death.

Amanda Sheldon, a spokeswoman for Medtronic, admitted that the company had received previous reports of patients brought to the hospital which may be related to this case. They haven’t confirmed yet if these cases were really related or if there were deaths that occurred.

Less than half a million patients were using the MiniMed Paradigm Insulin Infusion Sets worldwide which are being replaced every two or three days. Some patients may have stock of this device. The recall is for those with manufacture date of between Oct 2001 and June 2013.

Patients may visit the FDA’s website for details or call Medtronic directly at 1-888-204-7616.

The insulin pumps were being used by diabetic patients as replacement for injections as maintenance of their blood levels. The device pumps small amounts of insulin throughout the day and may be brought anywhere. It has an infusion set that has a small tube attached under the patient’s skin.

Medtronic had also released a message to stop using the infusion set and call their hotline immediately if a patient notices a leak on the insulin pump. It is an obvious indicator that the pump is not working properly.