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Active substance(s): ATENOLOL / CHLORTHALIDONE

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11 September 2015


Package leaflet: Information for the patient
Read all of this leaflet carefully before you start
taking this medicine because it contains
important information for you.
• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your
doctor or pharmacist.
• This medicine has been prescribed for you only.
Do not pass it on to others. It may harm them,
even if their signs of illness are the same as
• If you get any side effects, talk to your doctor or
pharmacist. This includes any possible side
effects not listed in this leaflet. See section 4.
What is in this leaflet

Pharma code 21

1. What Co-Tenidone is and what it is used for
2. What you need to know before you take
3. How to take Co-Tenidone
4. Possible side effects
5. How to store Co-Tenidone
6. Contents of the pack and other information


What Co-Tenidone is and what it is used

Co-Tenidone is a combination of two drugs.
Atenolol is a beta blocker and chlortalidone is a
diuretic. Beta blockers have an action on the
heart; to slow the pulse rate and reduce the force
of contraction of the heart muscle. Diuretics
increase urine output and so reduce fluid
retention. This combined action leads to a
lowering of your blood pressure.
Co-Tenidone is used to treat people with high
blood pressure.


What you need to know before you take

Do not take Co-Tenidone:
• if you are allergic to the active substances or
any of the other ingredients of this medicine
(listed in section 6)
• if you are pregnant or breast-feeding
• if you have an unusually slow heart beat or low
blood pressure sometimes causing dizziness,
faintness or lightheadness on standing
• if you have a phaeochromocytoma (adrenal
gland tumor) unless adequately controlled by
• if you have metabolic acidosis (acidification of
the blood)
• if you have a second or third degree heart block
(a conduction defect of the heart) or a weak
heart (cardiogenic shock)
• if you have sick-sinus syndrome (slow and
irregular heart beat due to sino-atrial block)
• if you have unstable/uncontrolled heart failure
• if you have severe hardening of the arteries
affecting the circulation in your legs or feet
• if you have severe kidney failure.
Warnings and precautions
Talk to your doctor or pharmacist before taking
• if you have a history of asthma, wheezing or
have other problems with your breathing
• if you have liver or kidney problems
• if you have gout
• if you have first degree heart block, controlled
heart failure or Printzmetal’s angina (chest pain)
or any type of heart disease
• if you have history of allergic reactions
(swelling of the lips, face or neck leading to
severe difficulty in breathing; skin rash or hives)
• if you have diabetes as your low blood sugar
“hypo” warning signs may be less obvious
than usual. Your doctor may want to test your
blood sugar level at the beginning of this
• if you have thyroid problems
• if you are elderly
• if you have a diet low in potassium
• if you suffer from stomach problems.
Tell your doctor or dentist you are taking
Co-Tenidone tablets if you are to have an
operation requiring an anaesthetic.


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Your doctor may test the level of potassium in
your blood if you are taking digoxin or digitoxin,
are on a low potassium diet or if you have any
stomach complaints.
If you take Co-Tenidone for a long time your urine
will be tested regularly for sugar.
Co-Tenidone can affect or be affected by other
medicines you are using, including eye drops for
the treatment of glaucoma.
Other medicines and Co-Tenidone
Tell your doctor or pharmacist if you are taking,
have recently taken or might take any other
Talk to your doctor if you are taking any of the
• insulin or tablets to treat diabetes
• digoxin or digitoxin (used to treat heart
• non-steroidal anti-inflammatory drugs (NSAIDs)
e.g. indometacin or ibuprofen
• sympathomimetic (heart stimulating) drugs
such as dopamine, terbutaline, salmeterol,
salbutamol, ephedrine, adrenaline and
phenylpropranolamine. Ephedrine and
phenylpropranolamine may be present in
medicines for colds and nasal stuffiness
• lithium (use to treat manic depression)
• calcium channel blockers e.g. diltiazem,
verapamil or nifedipine
• medication to treat an irregular heart beat such
as disopyramide, amiodarone
• clonidine (another drug used to treat high
blood pressure)
• baclofen (used for relaxation of muscle)
• anaesthetics (medicines used for temporary
loss of bodily sensation).
Co-Tenidone with food,drink and alcohol
Do not drink alcohol while taking Co-Tenidone.
Pregnancy, breast-feeding and fertility
If you are pregnant or breast-feeding, think you
may be pregnant or are planning to have a baby,
ask your doctor or pharmacist for advice before
taking this medicine.
Driving and using machines
Co-Tenidone may cause dizziness or tiredness, if
affected do not drive or operate machinery.


How to take Co-Tenidone

Always take this medicine exactly as your doctor
or pharmacist has told you.Check with your
doctor or pharmacist if you are not sure.
The recommended dose is:
One Co-Tenidone 50 mg/12.5 mg tablet daily. This
may be increased to 100 mg/25 mg daily.
Dosage may be reduced.
Kidney problems
You may be prescribed a lower dose or you may
need to take your medicine less frequently.Please
speak to your doctor before taking this medicine if
you have severe kidney problems.
Children and adolescents < 18 years
Co-Tenidone is not recommended for use in
children and adolescents < 18 years.
If you take more Co-Tenidone than you should
If you (or someone else) take too many tablets all
together, or if you think a child has swallowed any
of the tablets, contact your nearest hospital
casualty department or your doctor immediately.
An overdose is likely to cause low blood pressure
(feeling faint, dizzy, shaky and weak), slow heart
beat, difficulty in breathing and heart failure/
attack. Please take this leaflet, any remaining
tablets and the container with you to the hospital
or doctor so that they know which tablets were
If you forget to take Co-Tenidone
If you forget to take a tablet, take one as soon as
you remember, unless it is nearly time to take the
next one. Do not take a double dose to make up
for a forgotten tablet.


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CO-TENIDONE 50 mg/12.5 mg and
100 mg/25 mg TABLETS





11 September 2015


If you stop taking Co-Tenidone
Do not suddenly stop taking your tablets as side
effects can occur. If your treatment is to be
stopped your doctor will gradually reduce your
If you have any further questions on the use of
this product, ask your doctor or pharmacist.


Possible side effects

Reporting of side effects
If you get any side effects, talk to your doctor or
pharmacist. 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.


How to store Co-Tenidone

Like all medicines, this medicine can cause side
effects, although not everybody gets them.

Keep this medicine out of the sight and reach of

If the following happens, stop taking the tablets
and tell your doctor immediately or go to the
casualty department at your nearest hospital:
• an allergic reaction (swelling of the lips, face or
neck leading to severe difficulty in breathing;
skin rash or hives).
This is a very serious but rare side effect. You may
need urgent medical attention or hospitalisation.

Store in a cool dry place at or below 25°C. Protect
from light.
Do not use this medicine after the expiry date
which is stated on the carton after EXP.The expiry
date refers to the last day of that month.
Do not throw away any medicines via wastewater
or household waste. Ask your pharmacist how to
throw away medicines you no longer use. These
measures will help to protect the environment.

If you have a history of asthma or psoriasis
(patches of flaky, thickened and sore skin) you
may experience a worsening of the symptoms of
these conditions.
Tell your doctor if you experience any of the
Common: may affect up to 1 in 10 people

slow heart beat
cold hands and feet
stomach upset
feeling unwell
high uric acid in blood (this can be detected
from a blood test)
• low blood levels of potassium which can cause
muscle weakness, twitching or abnormal heart
• low blood levels of sodium which can cause
tiredness and confusion, muscle twitching, fits
and coma
• sugar intolerance.


Contents of the pack and other

What Co-Tenidone contains:
• The active substances are atenolol and
Each tablet of Co-Tenidone 50 mg/12.5 mg
contains atenolol 50 mg and chlortalidone
12.5 mg.
Each tablet of Co-Tenidone 100 mg/25 mg
contains atenolol 100 mg and chlortalidone
25 mg.
• The other ingredients are magnesium
carbonate, maize starch, povidone (E1201),
sodium starch glycolate and magnesium
stearate (E572). The tablet coating contains
hypromellose (E464), purified talc (E553b),
polyethylene glycol (E1520), yellow, red and
black iron oxides (E172) and titanium dioxide

What Co-Tenidone looks like and contents of the
• The 50 mg/12.5 mg are brown, film-coated,
round, biconvex tablets, engraved: 3H2.
• sleep disturbances
• The 100 mg/25 mg are brown, film-coated,
• elevated liver function test.
round, biconvex tablets, engraved: 4H2.
• The product comes in packs of 10, 20, 28, 30,
Rare: may affect up to 1 in 1,000 people
56, 60, 100, 250, 500 and 1000 tablets.
• low white blood cell and platelet count in blood
Not all pack sizes may be marketed.
• bleeding underneath the skin
Marketing Authorisation Holder and Manufacturer
• unusual bleeding or unexplained bruising
Marketing Authorisation holder and company
• mood changes
responsible for manufacture: TEVA UK Limited,
• nightmares
Eastbourne, BN22 9AG.
• confusion
• abnormal condition of mind
This leaflet was last revised: August 2015
• seeing and hearing things that are not real
Uncommon: may affect up to 1 in 100 people

abnormal sensation of skin
dry eyes
disturbed vision
heart failure deterioration
heart block
rapid fall of blood pressure when standing up
feeling faint
difficulty in breathing or wheezing
dry mouth
liver disease
inflammation of the pancreas that may cause
intense, persistent pain in the upper abdomen.
Symptoms may include nausea, constipation,
and jaundice
hair loss
skin rash
patchy inflamed skin
inability to develop or maintain an erection of
the penis.

PL 00289/0736 & 0737

Very rare: may affect up to 1 in 10,000 people
• increase in anti-nuclear antibody.
Not known: frequency cannot be estimated from
the available data
• constipation
• Lupus-like syndrome (a disease where the
immune system produces antibodies that
attacks mainly skin and joints)
160 x 323


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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.