A possible link has been made between Dronedarone, which is currently used to prevent atrial fibrillation, and two cases of liver failure requiring transplant
DOCTORS HAVE been asked to closely monitor patients taking a drug used to control atrial fibrillation, a rhythm disturbance in the heart, following reports of liver damage possibly associated with the medication.
Dronedarone, which is marketed under the trade name Multaq, was licensed in 2009 and is used to prevent recurrence of atrial fibrillation.
Atrial fibrillation happens when the atria (the upper chambers of the heart) contract irregularly and rapidly. Multaq is used to prevent the fibrillation coming back or to lower the heart rate.
Atrial fibrillation is one of the main causes of stroke; it is estimated that every fifth stroke is due to the arrhythmia. The resulting stroke, which occurs after a clot travels from the fibrillating heart to the brain, is often severe. About 10,000 people develop a stroke in the Republic every year.
Dronedarone works mainly by blocking channels through which charged particles of potassium move in and out of the muscle cells, causing the excessive electrical activity that leads to atrial fibrillation and rapid heart rate.
At its meeting in January the European Medicines Agency (EMA) committee charged with overseeing drug safety decided urgent regulatory action was needed to manage the possible risk of severe liver problems with dronedarone.
It said it had “become aware of reports of severe liver injury in patients treated with the medicine. These include two cases of liver failure requiring a transplant, reported in December 2010.
“The two cases occurred four and a half and six months after starting treatment in patients with normal liver function before treatment.”
The EMA has recommended that doctors carry out liver function tests on patients prescribed dronedarone prior to starting treatment and at one month intervals for the subsequent six months.
These blood tests must then be repeated nine and 12 months post commencement of treatment.
The agency and the Irish Medicines Board have also requested that patients currently taking the drug be contacted within a month so that liver function tests can be performed, followed by a testing regime similar to that for people starting dronedarone for the first time.
If the level of a liver enzyme called alanine transaminase (ALT) remains persistently three times greater than normal, the drug must be withdrawn.
Patients taking dronedarone are asked to contact their doctor if they notice any of the following: sustained new-onset abdominal pain, nausea, vomiting, fever, fatigue, jaundice, dark coloured urine or itching.