How does it work?

Cordarone X tablets contain the active ingredient amiodarone,which is a type of medicine called an antiarrhythmic. (NB. Amiodarone tabletsare also available without a brand name, ie as thegeneric medicine.) Amiodarone is used to controlabnormal heartbeats.

The heart's pumping action is controlled by electrical signalsthat pass through the heart muscle. The electrical signals cause the two pairsof heart chambers (left and right atria and ventricles) to contract in aregular manner that produces the heartbeat. If the electrical activity in theheart is disturbed for any reason, irregular heartbeats (arrhythmias) ofvarious types can result. These can seriously undermine the pumping action ofthe heart and result in inefficient blood circulation around the body.

Amiodarone works by slowing the electrical impulses in theheart muscle. This helps to regulate and restore disturbances in the heartrhythm.

Amiodarone is used to treat a variety of different types offast, abnormal heart rhythms (these are known as tachyarrhythmias). It is usedfor severe rhythm disorders when other treatments are not effective or cannotbe used.

What is it used for?

• Fast, abnormal heart rhythms (tachyarrhythmias) associated with Wolff-Parkinson-White syndrome
• Fast, abnormal heart rhythms (tachyarrhythmias), including supraventricular, nodal and ventricular tachycardias, atrial fibrillation, atrial flutter and ventricular fibrillation, when other drugs cannot be used.

Warning!

• It is recommended that you avoid drinking excessive amounts of alcohol while taking this medicine.
• It is also recommended that you avoid drinking grapefruit juice, as this may increase the level of this medicine in your blood and therefore increase the chance of side effects.
• Amiodarone can cause serious adverse reactions affecting the eyes, heart, lung, liver, thyroid gland, skin and peripheral nervous system. Because these reactions may be delayed, people on long-term treatment should be carefully monitored by their doctor.
• You should have a blood test to check the levels of thyroid hormones in your blood (thyroid function tests) before starting treatment, every six months throughout treatment and for several months after stopping treatment with this medicine.
• The electrical activity in your heart should be monitored using an ECG, and the amount of potassium in your blood checked, before you start treatment with this medicine. Your heart should be monitored regularly with an ECG thoughout treatment.
• You should have a blood test to monitor your liver function (liver function test) before starting treatment and every six months during treatment.
• You should have an eye test every year while you are taking this medicine. If you get blurred vision or decreased vision you should tell your doctor immediately so that your eyes can be checked.
• Tell your doctor if you get an unexplained non-productive cough, shortness of breath, fatigue, fever or weight loss during treatment, so that your lung function can be checked. This might invlove having a chest X-ray.
• This medicine can make your skin unduly sensitive to sunlight. For this reason you should avoid exposing your skin to sunlight or sunlamps while taking this medicine and for several months after stopping treatment. If exposure to sunlight cannot be avoided, use protective measures such as sun-creams or protective clothing. Your doctor can prescribe you a high factor sun-cream.

Use with caution in

• Elderly people
• Heart failure
• People with severe electrical conduction disturbances within the heart (high grade atrio-ventricular block, bifascicular or trifascicular block or sinus node disease). This medicine should only be used in conjunction with an artificial pacemaker in these cases.

Not to be used in

• Slow heart rate caused by the pacemaker of the heart (sinus bradycardia)
• Failure of the electrical impulse that causes the heart to beat to leave the pacemaker of the heart, resulting in decreased heart function (sino-atrial heart block)
• History of, or current overactive or underactive thyroid gland
• Allergy to iodine
• Pregnancy
• Breastfeeding
• Rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption (Cordarone X tablets contain lactose).

This medicine should not be used if you are allergic to one orany of its ingredients. Please inform your doctor or pharmacist if you havepreviously experienced such anallergy.If you feel you haveexperienced an allergic reaction, stop using this medicine and inform yourdoctor or pharmacist immediately.

Pregnancy and Breastfeeding

Certain medicines should not be used during pregnancy orbreastfeeding. However, other medicines may be safely used in pregnancy orbreastfeeding providing the benefits to the mother outweigh the risks to theunborn baby. Always inform your doctor if you are pregnant or planning apregnancy, before using any medicine.

• This medicine should not be used during pregnancy as it may be harmful to the unborn baby. Seek medical advice from your doctor.
• This medicine passes into breast milk and women taking this medicine should therefore not breastfeed. Seek medical advice from your doctor.

Label warnings

• Avoid exposure of skin to direct sunlight or sun lamps.

Side effects

Medicines and their possible side effects can affect individualpeople in different ways. The following are some of the side effects that areknown to be associated with this medicine. Because a side effect is statedhere, it does not mean that all people using this medicine will experience thator any side effect.

• Micro-deposits in the protective outer layer of the eye (corneal microdeposits), reversible on withdrawal of treatment, which can cause drivers to be dazzled by headlights at night.
• Abnormal reaction of the skin to light, usually a rash (photosensitivity)
• Reversible grey/blueish tint to skin exposed to light, particularly the face
• Nausea and vomiting
• Metallic taste
• Slower than normal heart beat (bradycardia)
• Interference with functioning of the thyroid gland (over or under activity)
• Difficulty in sleeping (insomnia)
• Nightmares
• Lung disorders such as inflammation or scarring and stiffening causing breathlessness
• Tremor
• Fatigue
• Disorder of the peripheral nerves causing weakness and numbness (peripheral neuropathy)
• Disorder of the muscles (myopathy)
• Hair loss (alopecia)
• Headache
• Balance problems involving the inner ear (vertigo)
• New or worsening abnormal heartbeat
• Inflammation of the epididymis which has spread to involve the testis (epididymo-orchitis)
• Impotence
• Liver problems

The side effects listed above may not include all of the sideeffects reported by the drug'smanufacturer.For moreinformation about any other possible risks associated with this medicine,please read the information provided with the medicine or consult your doctoror pharmacist.

How can this medicine affect other medicines?

It is important to tell your doctor or pharmacist what medicinesyou are already taking, including those bought without a prescription andherbal medicines, before you start treatment with this medicine. Similarly,check with your doctor or pharmacist before taking any new medicines whiletaking this one, to ensure that thecombination is safe.

The following medicines may increase the risk of a 'prolonged QTinterval' on the heart monitoring trace (ECG) if they are taken in combinationwith amiodarone. As this could increase the risk of an irregular heartbeatcalled Torsades de Pointes, these medicines must not be taken withamiodarone:

• other anti-arrhythmics, eg disopyramide, procainamide, quinidine, sotalol, bretylium
• intravenous injection of the antibiotics erythromycin, pentamidine or co-trimoxazole
• tricyclic antidepressants, eg doxepin, amitriptyline
• lithium
• maprotiline
• the antihistamines terfenadine, astemizole and mizolastine
• antimalarials, eg chloroquine, quinine, mefloquine, halofantrine
• certain antipsychotics, eg chlorpromazine, thioridazine, fluphenazine, pimozide, haloperidol, amisulpiride and sertindole.

There is an increased risk of slowed conduction of electricalsignals within the heart and a slow heart rate if amiodarone is used with thefollowing; these medicines are not recommended in combination withamiodarone:

• beta-blockers such as propranolol
• the calcium channel blockers diltiazem and verapamil.

The following medicines are not recommended for use incombination with amiodarone because they may lower the amount of potassium ormagnesium in the blood, which could increase the risk of side effects on theheart:

• stimulant laxatives, eg senna
• diuretics
• corticosteroids by mouth or injection
• tetracosactide
• intravenous amphotericin.

Amiodarone may increase the blood levels of the followingmedicines and their dose may therefore need to be reduced if they are used incombination with amiodarone:

• anticoagulants such as warfarin
• ciclosporin
• digoxin
• flecainide
• phenytoin.

Other medicines containing the same active ingredient

Amiodarone tablets and injection are also available as thegeneric medicine, ie without a brand name.