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150 & 300 mg Tablets
Propafenone Hydrochloride
Read all of this leaflet carefully before you start taking this medicine.
• Keep this leaflet as you may need to read it again
• This leaflet provides a summary of the information currently available for Arythmol
• For further information or advice ask your doctor or pharmacist
• This medicine is for you only and should never be given to anyone else, even if they appear to
have the same symptoms as you
• Tell your doctor or pharmacist if you experience any side effects
Leaflet Contents:
1. What is Arythmol & what is it used for?
2. What should you know before taking Arythmol?
3. How should you take your Arythmol?
4. Possible side effects of Arythmol.
5. How should you store Arythmol?
6. Further information about Arythmol.
1. What is Arythmol & what is it used for?
Arythmol belongs to a group of medicines called antiarrhythmic agents. Arythmol slows down the
heart rate and helps to regulate the heartbeat. Arythmol tablets are used to treat and prevent
arrhythmias (abnormal heart rhythms).
2. What should you know before taking Arythmol?
If the answer to any of these questions is YES, tell your doctor or pharmacist BEFORE you start to
take Arythmol.


Are you sensitive (allergic) to propafenone hydrochloride or any of the other ingredients in the
tablets (listed in section 6)?
Have you had a heart attack in the previous 3 months?
Are you pregnant or planning to become pregnant, or are you breast feeding?
Do you suffer from heart failure or any heart problems other than your abnormal heart rhythm?
Do you have a heart condition called Brugada Syndrome, which causes you to have a potentially
life-threatening heart rhythm?
Do you have an unusually slow heart rate or hypotension (low blood pressure)?
Do you suffer from any breathing problems, such as asthma or chronic bronchitis or emphysema?
Have you been diagnosed as having the condition known as myasthenia gravis?
Has your doctor told you that you have a disturbance in the salts (e.g. sodium or potassium) in
your blood?
Are you going to be receiving an anaesthetic?
Are you taking any of the following?
medicines that affect the activity of the heart such as amiodarone, digoxin, quinidine;
tablets to prevent blood clots (e.g. warfarin);
antibiotics (e.g. erythromycin or rifampicin);
any of the group of medicines known as beta-blockers (these are used to treat high blood
any antiviral agents (e.g. ritonavir);
any of the group of medicines known as major tranquillisers, or an antidepressant of the tricyclic
or related group (e.g. amitriptyline, dothiepin, desipramine);
any other antidepressants, such as venlafaxine, fluoxetine, paroxetine;


cimetidine (an ulcer medicine), ciclosporin (an immunosuppressant, used after transplant
operations, or in the treatment of arthritis or psoriasis), theophylline (used in the treatment of
asthma), ketoconazole (an antifungal agent), phenobarbitol (for epilepsy) or grapefruit juice.

• If you need to have an operation it is important to tell the surgeon or dentist, Arythmol may affect
the anaesthetic or other treatments used.
• If you have a pacemaker, it may need to be altered.
• Arythmol is NOT suitable for children.
• Your doctor may perform ECGs and blood pressure monitoring prior to and during treatment to
monitor your individual dose.
It is NOT advisable to drive, operate machinery or do anything that requires you to be alert until you
know how the tablets affect you. This is because Arythmol can cause blurred vision, dizziness,
tiredness and low blood pressure in some people.
3. How should you take Arythmol?
Follow your doctor’s directions about when and how to take your tablets and look at the label on the
carton. Your pharmacist will also help if you are not sure. The number of tablets that you will need to
take will be decided by your doctor.
This may be between one Arythmol 150 mg tablet three times a day to one Arythmol 300 mg tablet
three times a day.
You may need a lower dose of Arythmol if you are elderly, if you have problems with your kidneys or
liver, or if you have a low bodyweight.
Swallow your tablets without chewing them. It is best to take them after food with some water. Do not
take with grapefruit juice.
(AN OVERDOSE) you should contact a doctor or go to the nearest hospital casualty department
IMMEDIATELY, taking your tablets with you.
remember, unless it is almost time for your next dose. If it is, do not take the missed dose at all. Never
double up on a dose to make up for the one you have missed.
IF YOU STOP TAKING ARYTHMOL, without your doctor’s advice, your condition may get
worse. It is important that you keep taking these tablets until your doctor tells you to stop. Do NOT
stop just because you feel better.
4. Possible side effects of Arythmol.
As well as benefits, all medicines may sometimes have unwanted effects in some people.
Tell your doctor IMMEDIATELY if you develop any of the following conditions:
• a rash, itching or skin reddening or other signs of an allergic reaction such as difficulty breathing.
Although these are rare, they can be serious.
• yellowing of the skin and/or eyes, as these may be a sign of liver problems
• you start to bruise easily or if you develop a very sore throat with a high fever, as in very rare
cases, treatment may affect the amount of white blood cells and platelets in the blood.
Other side effects with Arythmol may include:
Very Common side effects (occurring in more than 1 in 10 users):


Irregular (slow or fast) heart beat
Heart palpitations (being aware of your heart beat)

Common side effects (occurring in 1 to 10 users in 100):
- Anxiety
- Difficulty sleeping
- Headache
- Alteration of taste or a bitter taste
- Blurred vision
- Abnormal heart rhythm
- Shortness of breath
- Stomach pain
- Feeling or being sick
- Diarrhoea
- Constipation
- Dry mouth
- Liver disorders
- Chest pain
- Feeling tired or weak
- Fever
Uncommon side effects (occurring in 1 to 10 users in 1000):
- Reduction in blood platelets, which increases risk of bleeding or bruising
- Loss of appetite
- Nightmares
- Fainting
- Ataxia (problems with or loss of coordination)
- Low blood pressure
- Vertigo (spinning sensation)
- A tingling or pricking sensation of the skin
- Numbness
- Bloating
- Flatulence (passing wind/gas)
- Redness of skin and itchy skin
- Impotence
The following are side effects with an unknown frequency:
- Severe reduction in the number of white blood cells which makes infections more likely
- Confusion
- Seizures
- Tremor (feeling shaky)
- Rigidity (stiffness)
- Restlessness
- Life threatening irregular heart beat
- Heart problems which can cause shortness of breath or ankle swelling
- A fall in the blood pressure on standing up which may cause dizziness, light headedness or
- Yellowing of the skin or whites of the eyes caused by liver or blood problems
- Retching
- Lupus-like syndrome (an allergic condition which causes joint pain, skin rashes and fever)
A reversible drop in sperm count has occasionally been reported with high doses.

If you experience any other unusual symptoms whilst taking your tablets, tell your doctor or
Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side
effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme
at: By reporting side effects you can help provide more information on
the safety of this medicine.
5. How should you store Arythmol?
Your tablets should be stored in a safe place out of the reach and sight of children. They should be
kept below 30 °C and in their original packaging.
Do NOT use Arythmol after the expiry date printed on the packaging. The date refers to the last day
of that month.
If your doctor decides to stop the treatment, return any leftover tablets to your pharmacist. Only keep
the tablets if your doctor tells you to. Do not dispose of the leftover tablets carelessly (e.g. down the
toilet or in with your general rubbish).
6. Further information about Arythmol.
What Arythmol contains
· The active substance is propafenone hydrochloride. Each tablet contains either 150mg or 300mg of
propafenone hydrochloride.
· The other ingredients are microcrystalline cellulose, maize starch, hypromellose (Type 2910),
sodium croscarmellose, purified water, macrogol 6000, titanium dioxide (E171), macrogol 400 and
magnesium stearate.
What Arythmol looks like and contents of the pack
White to off white film coated tablets. The inscription on the tablets is 150 or 300 on one side.
The tablets are available in two strengths containing either 150mg or 300mg of propafenone
Each pack of Arythmol 150 mg tablets contains 90 tablets.
Each pack of Arythmol 300 mg tablets contains 60 tablets.
Marketing Authorisation Holder: Abbott Laboratories Ltd., Abbott House, Vanwall Business Park,
Vanwall Road, Maidenhead, Berkshire SL6 4XE, United Kingdom
Famar Lyon, 29, avenue Charles de Gaulle, 69230 Saint-Genis-Laval, France

The leaflet was last revised in December 2014.

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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.