Letterkenny University Hospital is calling on patients of the INR Clinic to telephone for advice on medication.
The ransomware attack on the HSE IT systems is having an ongoing impact on services at Letterkenny University Hospital.
The patient records system is not currently accessible which means that clinical staff are unable to contact patients.
Patients who are taking warfarin medication and have concerns about checking their INR are asked to telephone 074 9104473 between 10am and 12noon on Tuesdays and Wednesdays for advice.