Myorythm Tablets

MYORYTHM contains amiodarone hydrochloride which belongs to a group of medicines called anti-dysrhythmics. It works by controlling the uneven beating of your heart (called ‘dysrhythmias’). Taking the tablets helps your heartbeat to return to normal.

MYORYTHM tablets can be used to:

• Treat uneven heartbeats where other medicines either have not worked or cannot be used;
• treat an illness called Wolff-Parkinson-White Syndrome. This is where your heart beats unusually fast;
• treat other types of fast or uneven heartbeats known as ‘atrial flutter’ or ‘atrial fibrillation’. MYORYTHM tablets are used only when other medicines cannot be used; or
• treat fast heartbeats which may happen suddenly and may be uneven. MYORYTHM tablets are used only when other medicines cannot be used.

Do not take MYORYTHM:

• If you are hypersensitive (allergic) to amiodarone hydrochloride, iodine or any of the other ingredients of MYORYTHM (listed in section 6).
• If you a slower than usual heartbeat (called ‘sinus bradycardia’) or an illness called ‘sino-atri al’ heart block.
• If you have ever had thyroid problems. Your doctor should test your thyroid function before giving you this medicine.
• If you are pregnant.
• If you are breastfeeding.
• If you are taking certain other medicine which could affect your heartbeat (see Other medicine and MYORYTHM).
• If you are under the age of 18 years.

Warnings and precautions

Special care should be taken with MYORYTHM:

• If you are scheduled for surgery (inform your anaesthetist that you are taking MYORYTHM);
• if you have a condition called porphyria (group of disorders resulting from build-up of certain chemicals related to red blood cell proteins;
• if you have heart failure;
• if you have a pacemaker or implantable cardioverter defibrillator (ICD);
• if you currently take a medicine containing sofosbuvir for the treatment of hepatitis C as it may result in a life-threatening slowing of your heartbeat. Your doctor may consider alternative treatments. If treatment with MYORYTHM and sofosbuvir is needed, you may require additional heart monitoring;
• if you have a slow or irregular heartbeat or heart rhythm problems;
• if you have any complications with your thyroid;
• if you have any problems with your eyesight;
• if you have liver problems;
• if you have a condition in which your nerves are damaged;
• if you have any problems with your lungs or have asthma; or
• if you experience shortness of breath or worsening of existing shortness of breath, a persistent cough and fatigue.

Exposed to the sun for long periods during the day should be avoided, because your skin will become more sensitive to the sun and may burn, tingle or severely blister when exposed.

Treatment with MYORYTHM should be discontinued if you develop the following:

• Severe blistering rash in which layers of the skin may peel off to leave large areas of raw exposed skin over the body. You may also feel generally unwell, have a fever, chills and aching muscles this may be condition is called Toxic Epidermal Necrolysis;
• blistering or peeling of the skin around the lips, eyes, mouth, nose and genitals, flu-like symptoms and fever. This condition is called Stevens-Johnson syndrome.

Before starting MYORYTHM treatment, your doctor may perform an ECG and blood tests. Monitoring of ECG is recommended during treatment.

Do not share medicines prescribed for you with any other person. Always use MYORYTHM exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.

• The starting dose is MYORYTHM 200 mg three times a day and may be continued for 1 week.
• The dosage is then lowered MYORYTHM to 200 mg twice daily for one week.
• The dose will then be lowered to MYORYTHM to 200 mg daily unless you are told otherwise.

In some cases, your doctor may then decide to either increase or lower the amount you take each day. This will depend on how you react to MYORYTHM.

MYORYTHM should not be taken by children or adolescents. Your doctor will tell you how long your treatment with MYORYTHM will last. Do not stop treatment early because the dangerous uneven heartbeat may return.

If you have the impression that the effect of MYORYTHM is too strong or too weak, tell your doctor or pharmacist.

If you take more MYORYTHM than you should

If you take more MYORYTHM tablets than you should, tell a doctor or go to a hospital casualty department straight away. Take the medicine pack with you. This is so the doctor knows what you have taken. The following effects may happen: feeling dizzy, faint or tired, confusion, slow heartbeat, damage to the liver or being sick.

If you forget to take MYORYTHM

If you forget a dose, take it as soon as you remember it. However, if it is nearly time for the next dose, skip the missed dose. Do not take a double dose to make up for forgotten individual doses.

If you stop taking MYORYTHM

Keep taking MYORYTHM until your doctor tells you to stop. Do not stop taking MYORYTHM just because you feel better. If you stop taking this medicine, without the consent of your doctor, the uneven heartbeats may come back. This could be dangerous.

MYORYTHM can have side effects. Not all side effects reported for MYORYTHM are included in this leaflet. Should your general health worsen or if you experience any untoward effects while taking MYORYTHM, please consult your health care provider for advice.

If any of the following happens, stop taking MYORYTHM and tell your doctor immediately or go to the casualty department at your nearest hospital:

• Swelling of the hands, feet, ankles, face, lips and mouth or throat, which may cause difficulty in swallowing or breathing;
• skin rash or itching;
• fainting.

These are all very serious side effects. If you have them, you may have had a serious reaction to MYORYTHM. You may need urgent medical attention or hospitalisation.

Tell your doctor immediately or go to the casualty department at your nearest hospital if you notice any of the following:

• Severe blistering rash in which layers of the skin may peel off to leave large areas of raw exposed skin over the body. You may also feel generally unwell, have a fever, chills and aching muscles (Toxic Epidermal Necrolysis);
• blistering or peeling of the skin around the lips, eyes, mouth, nose and genitals, flu-like symptoms and fever. This could be a condition called Stevens-Johnson syndrome;
• inflammation of the skin characterised by fluid filled blisters (bullous dermatitis);
• you have flu like symptoms and a rash on the face followed by an extended rash with a high temperature, increased levels of liver enzymes seen in blood tests and an increase in a type of white blood cell (eosinophilia) and enlarged lymph nodes (DRESS); or
• difficulty breathing or tightness in the chest, coughing which will not go away, wheezing, weight loss and fever. This could be due to inflammation of your lungs which can be very dangerous.

These are all serious side effects. You may need urgent medical attention.

Tell your doctor if you notice any of the following:

Frequent side effects:

• Feeling extremely restless or agitated, weight loss, increased sweating and being unable to stand the heat. These could be signs of an illness called ‘hyper-thyroidism’;
• feeling extremely tired, weak or ‘run-down’, weight gain, being unable to stand the cold, constipation and aching muscles. These could be signs of an illness called ‘hypo-thyroidism’;
• trembling when you move your arms or legs;
• nightmares and sleep disorders;
• blurred eyesight or seeing a coloured halo in dazzling light;
• slower than normal heart rate;
• feeling sick (nausea) or being sick (vomiting), change in the way things taste, constipation;
• changes in the amount of liver enzymes at the beginning of treatment. This can be seen in blood tests;
• blue or grey marks on parts of your skin exposed to sunlight, especially the face; or
• scaly and itchy rash (eczema).

Less frequent side effects:

• Feeling tired, faint, dizzy or having pale skin. These could be signs of anaemia;
• you may bleed or bruise more easily than usual. This could be because of a blood disorder (called ‘thrombocytopenia’);
• feeling unwell, confused or weak, feeling sick (nausea), loss of appetite, feeling irritable. This could be an illness called ‘syndrome of inappropriate anti-diuretic hormone secretion’ (SIADH):
• decreased appetite;
• feeling numb or weak, tingling or burning feelings in any part of your body;
• headache (which is usually worse in the morning or happens after coughing or straining), feeling sick (nausea), fits, fainting, eyesight problems or confusion can occur. These could be signs of problems with your brain;
• balance problems, feeling dizzy (vertigo);
• moving unsteadily or staggering, slurred or slow speech;
• you get loss of eyesight in one eye or your eyesight becomes dim and colourless. Your eyes may feel sore or tender and feel painful to move. This could be an illness called ‘optic neuropathy’ or ‘neuritis;
• you may experience eye conditions such as swelling of the optic disc (Papilloedema), deterioration of the clear outer layer of the eye (corneal degeneration), increased sensitivity to light (photosensitivity), general eye discomfort, areas of reduced or lost vision (scotoma), clouding or loss of transparency in the eye's lens (lens opacities), and progressive loss of central vision (macular degeneration). These conditions have been reported in some cases;
• your heartbeat becomes even more uneven or erratic. This can lead to a heart attack, so you should go to hospital straight away;
• feeling faint, dizzy, unusually tired and short of breath. These could be signs of a very slow heartbeat (especially in people over 65 years old) or other problems with your heart’s natural beat;
• skin rash caused by narrow or blocked blood vessels (called ‘vasculitis’);
• dry mouth;
• yellowing of the skin or eyes (jaundice), feel tired or sick, loss of appetite, stomach pain or high temperature. These can be signs of liver problems or damage, which can be very dangerous;
• skin redness during radiotherapy;
• skin rashes;
• red, scaly patches of skin, loss of hair or loosening of nails (called ‘exfoliative dermatitis’);
• hair loss, balding;
• swelling of the testicles;
• difficulty in getting or maintaining an erection or in ejaculating; or
• higher than normal level of creatinine in the bloodstream.

Side effects with frequency unknown:

• Granulomas, small red lumps on the skin or inside the body which are seen by X-ray;
• small area of inflammation or irritation that occurs in the bone marrow;
• confusional state/ delirium (a sudden and significant confusion and disorientation);
• movements that you cannot control, mainly of the tongue, mouth, jaw, arms and legs (Parkinsonism);
• a distorted sense of smell (parosmia);
• chest pain and shortness of breath and irregular heartbeat. These could be signs of a condition called “Torsade de pointes”;
• coughing blood due to bleeding from the lungs;
• severe stomach pain which may reach through to your back. This could be a sign of pancreatitis;
• hives (itchy, lumpy rash); or
• lupus-like syndrome (a disease where the immune system attacks various parts of the body and leading to pain, stiffness and swelling in joint and red skin, sometimes in the shape of butterfly wings on the face.

If you notice any side effects not mentioned in this leaflet, please inform your doctor or pharmacist.

Reporting of side effects

If you get side effects, talk to your doctor or pharmacist. You can also report side effects to SAHPRA via the “6.04 Adverse Drug Reaction Reporting Form”, found online under SAHPRA’s publications: https://www.sahpra.org.za/Publications/Index/8. By reporting side effects, you can help provide more information on the safety of MYORYTHM.

Store all medicines out of reach of children.

Store at or below 25 °C.

Store in the original container until required for use.

Do not use this medicine after the expiry date printed on the label.

Return all unused medicines to your pharmacist.

Do not dispose of unused medicine in drains or sewerage systems (e.g., toilets).