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Active substance(s): LOSARTAN POTASSIUM

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25mg, 50mg AND 100mg
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 further questions, please ask your
doctor or your pharmacist.
• This medication has been prescribed for you
only. Do not pass it on to others. It may harm
them, even if their symptoms 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.
1. What your medicine is and what it is used for
2. What you need to know before you take your
3. How to take your medicine
4. Possible side effects
5. How to store your medicine
6. Contents of the pack and other information
The name of your medicine is Losartan potassium
25mg, 50mg or 100mg film-coated tablets. Your
medication is referred to as Losartan potassium
tablets or Losartan throughout this leaflet.



Losartan belongs to a group of medicines known as
angiotensin-II receptor antagonists.
Angiotensin II is a chemical in your body, which
tightens your blood vessels making it harder for the
blood to pass through them and causes your blood
pressure to increase.
Losartan blocks this effect, causing the blood vessels
to relax and so lowers your blood pressure.
Your doctor has prescribed Losartan to:
• treat hypertension (high blood pressure) in adults
and in children and adolescents 6-18 years of age
• protect the kidney in hypertensive type 2
diabetic patients with laboratory evidence of
impaired renal function and proteinuria ≥ 0.5mg
per day (a condition in which urine contains an
abnormal amount of protein)

• reduce the risk of stroke in hypertension with
left ventricular hypertrophy (thickening of the
heart muscle)
• treat chronic heart failure when treatment with
ACE inhibitors (angiotensin-converting enzyme
inhibitors - medicines used to lower blood pressure)
is not considered suitable by your doctor

Children and adolescents
Losartan has been studied in children. For more
information, talk to your doctor. Losartan is not
recommended for use in children suffering from
kidney or liver problems, or children under the age of
6 years old, as limited data are available in these
patient groups.


Taking other medicines
Before you start to take Losartan tell your doctor or
pharmacist about any other medication that you are
taking or plan to take, including medicines you have
bought without a prescription, herbal medicines and
natural products.


DO NOT take Losartan if you:
• are allergic (hypersensitive) to Losartan or any of
the other ingredients listed in section 6 of this leaflet
(Contents of the pack and other information)
• are pregnant, think you may be pregnant or you are
planning to become pregnant
• are breast-feeding
• have severe liver disease
If any of the above applies to you, do not take the
tablets. Talk to your doctor first and follow their advice.
Before you take Losartan, tell your doctor if you:
• have a history of angioedema (swelling of the face,
lips, throat and/or tongue) see also section 4,
Possible side effects
• suffer from liver or kidney problems
• have recently suffered from severe vomiting or
diarrhoea leading to an extreme loss of fluid and/or
salt in your body
• receive diuretics (medicines that increase the
amount of water that you pass out through your
kidneys) or are under dietary salt restrictions
leading to an extreme loss of fluid and salt in your
body (see section 3, Special dosage requirements)
• received a kidney transplant recently
• suffer from problems with your heart valves or heart
muscle (e.g. ‘aortic stenosis’ or ‘outflow
• suffer from heart failure, with or without renal
impairment or concomitant severe life-threatening
cardiac arrhythmias. Special caution is necessary
when you are treated with a beta-blocker
• if you suffer from coronary heart disease (caused
by a reduced blood flow in the blood vessels of the
heart) or from cerebrovascular disease (caused by
a reduced blood circulation in the brain)
• suffer from primary hyperaldosteronism (a
syndrome associated with increased secretion of
the hormone aldosterone by the adrenal gland,
caused by an abnormality within the gland)
• have a high level of potassium in your blood

In particular tell your doctor if you are taking:
• other blood pressure lowering medicines as they
may additionally reduce your blood pressure
• tricyclic antidepressants, antipsychotics, baclofen
or amifostine as these may lower your blood
pressure further
• lithium (used to treat certain types of mental illness)
• non-steroidal anti-inflammatory painkillers (for
example, Ibuprofen, Naproxen or Diclofenac);
COX-2 inhibitors (for example, celecoxib, etoricoxib
or lumiracoxib) or more than 3grams of aspirin a
• high-dose diuretics (tablets to help you lose water)
e.g. amiloride, triamterene, spironolactone
• potassium supplements, potassium sparing agents
or potassium-containing salt substitutes or heparin
Your doctor will decide whether you should take these
medicines with Losartan.
Taking Losartan with food and drink
Losartan can be taken with or without food.
Pregnancy and breast-feeding
You should not take Losartan in the first 12 weeks of
pregnancy, and you must not take it at all after the
13th week, as its use during pregnancy may possibly
be harmful to the baby. If you become pregnant while
taking Losartan, tell your doctor immediately. A switch
to a suitable alternative treatment should be carried
out in advance of a planned pregnancy. You must not
take Losartan if you are breast-feeding. Always ask
your doctor or pharmacist for advice before taking any
Driving and using machines
You should not drive or operate machinery, until you
know how you react to Losartan potassium tablets as
it may cause dizziness or drowsiness. If you
experience dizziness or drowsiness, you should
consult your doctor before attempting to drive or use



You should take the tablets with a drink of water. You
must take your tablets every day exactly as your
doctor has told you. It is important that you take the
tablets for as long as your doctor prescribes them.
Dose for Adults
Hypertension (high blood pressure)
The usual dose of Losartan for most adult patients is
one 50mg tablet once a day to control your blood
pressure over the 24-hour period. The maximal blood
pressure lowering effect should be reached 3-6 weeks
after beginning treatment.
If a 50mg daily dose is ineffective, your doctor may
prescribe a higher dose of 100mg.
Hypertension with left ventricular hypertrophy
(thickening of the heart muscle)
The usual dose of Losartan for most adult patients is
one 50mg tablet taken once a day.
Your doctor may also prescribe a low dose of a
diuretic and/or increase your daily dose of Losartan to
Hypertension and Type-2 diabetes
The usual dose of Losartan for most adult patients is
one 50mg tablet taken once a day. Your doctor may
increase your dose to 100mg based on how your
blood pressure responds to the medicine.
Losartan potassium tablets may be administered with
other blood pressure lowering medicines (e.g.
diuretics, calcium channel blockers, alpha- or
beta-blockers, and centrally acting agents) as well
as with insulin and other commonly used medicines
that decrease the level of glucose in the blood (e.g.
sulfonylureas, glitazones and glucosidase inhibitors).
Heart failure
Treatment usually starts with 12.5mg Losartan once a
day. Generally, the dose should be increased weekly
step-by-step (i.e. 12.5mg daily during the first week,
25mg daily during the second week, 50mg daily
during the third week, 100mg daily during the fourth
week, 150mg daily during the fifth week) up to a
maintenance dose determined by your doctor.
Special Dosage Requirements
Your doctor may prescribe a lower dose of 25mg once
a day if you:
• are over 75 years of age
• have liver problems
• are being treated with high dose diuretics (water
losing tablets)

The use of losartan is not recommended in patients
with severe hepatic impairment.
No dose adjustments are needed for patients with
kidney disease or patients on dialysis.
Children less than 6 years of age
Not recommended, as limited data is available in this
age group.
Hypertension (high blood pressure) in children
aged 6 to 18
For children who can swallow and who weigh:
• between 20 and 50kg: the recommended dose is
25mg once a day (your doctor may increase the
dose up to 50mg once a day)
• 50kg or over: the starting dose is 50mg once a
day (your doctor may increase the dose up to
100mg once a day).
The doctor will adjust the dose according to the weight
of the child and how their blood pressure responds to
the medicine. ALWAYS follow your doctor’s
instructions exactly.
If you take more Losartan potassium tablets than
you should
If you take too many tablets, contact your doctor
immediately or go to the nearest hospital casualty
department. Symptoms of an overdose may be low
blood pressure, fast heart beat or slow heart beat.
If you forget to take your medicine
Try to take Losartan each day as prescribed. If you
miss a dose, just carry on with the next dose as
normal. DO NOT take an extra tablet to make up the
If you stop taking your medicine
Do not stop taking your medicine without talking to
your doctor, even if you feel better. It is important to
continue the course of treatment prescribed to you by
your doctor.



Like all medicines Losartan may cause side effects.
They are generally mild and do not normally need
STOP taking Losartan and contact your doctor or
nearest casualty department immediately if you
develop any of these symptoms:

• an allergic or hypersensitivity reaction - symptoms
may include: rash, itching, hives, swelling of the
face, lips, throat or tongue which may cause
difficulty in breathing or swallowing; inflammation of
the blood vessels, causing hard, purple blotches on
the skin
• feeling of increased heart rate (palpitations), severe
chest pain (angina pectoris)
• inflammation of the liver (hepatitis) – may result in
yellowing of the eyes and skin
• anaemia, abnormal bruising or bleeding – may be
caused by a reduction in the number of blood cells
• difficulty in passing water or blood in the urine (may
be a sign of kidney problems)
• inflammation of the pancreas (pancreatitis) – you
may notice severe upper abdominal pain spreading
to the back
• unexplained muscle pain with dark (tea-coloured)
urine (rhabdomyolysis)
• stroke
Other side effects reported with Losartan
potassium tablets
Common (affects 1 to 10 patients in 100):
• feeling dizzy
• low blood pressure
• weakness or feeling very tired
• too little sugar in the blood (hypoglycaemia)
• too much potassium in the blood (hyperkalaemia)
- your doctor will take regular blood samples to
monitor the levels of potassium in your blood
Uncommon (affects 1 to 10 patients in 1,000):
• drowsiness
• headache
• nausea (feeling sick)
• vomiting (being sick)
• sleep disorders
• low blood pressure (due to excessive loss of water
from the body) or a rapid drop in blood pressure symptoms of which may be feeling light-headed or
dizzy, particularly when standing up
• shortness of breath
• severe constipation
• abdominal pain
• localised swelling (oedema)
• diarrhoea
• cough
Rare (affects 1 to 10 patients in 10,000):
• angioedema
• numbness or tingling sensation (paraesthesia)
• inflammation of blood vessels (vasculitis including
Henöch-Schonlein purpura)
• fainting
• very rapid and irregular heartbeat (atrial fibrillation)
• elevated blood alanine aminotransferase (ALT)
levels, usually resolved upon discontinuation of

Not known (cannot be estimated from the available
• migraine
• muscle and joint pains, back pain
• flu-like symptoms
• urinary tract infection
• increased sensitivity to the sun (photosensitivity)
• impotence
• low levels of sodium in the blood (hyponatraemia)
• depression
• generally feeling unwell (malaise)
• ringing, buzzing, roaring, or clicking in the ear

What Losartan looks like and the contents of the
Losartan comes in blister packs containing 28 tablets.
Losartan potassium 25mg tablet is available as a
white, oblong, plain, film-coated tablet.
Losartan potassium 50mg tablet is available as a
white, oblong, score-line, film-coated tablet.
Losartan potassium 100mg tablet is available as a
white, oblong, plain, film-coated tablet.

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.

Manufacturer responsible for batch release
Kent Pharmaceuticals Limited, Repton Road,
Measham, DE12 7DT, U.K.
Kent Pharmaceuticals Limited,
Crowbridge Road, Ashford, Kent, TN24 0GR, U.K.



Do not take the tablets after the expiry date shown on
the carton. The expiry date refers to the last day of
that month.
Do not remove the tablets from the blister pack until
you are ready to take them.
There are no special requirements to store the tablets
at a particular temperature.
Medicines should not be disposed of via wastewater
or household waste. Ask your pharmacist how to
dispose of medicines no longer required. These
measures will help to protect the environment


Marketing authorisation holder
Athlone Pharmaceuticals Limited, Ballymurray,
Co. Roscommon, Ireland.

Kent Pharmaceuticals Limited, Repton Road,
Measham, DE12 7DT, U.K.
Product licence number: PL 30464/0049,
PL 30464/0050 or PL 30464/0051
This leaflet was last revised October 2013.


What Losartan contains
The active ingredient in Losartan potassium tablets is
losartan potassium.
Losartan potassium 25mg film-coated tablets contain
25mg of losartan potassium.
Losartan potassium 50mg film-coated tablets contain
50mg of losartan potassium.
Losartan potassium 100mg film-coated tablets contain
100mg of losartan potassium.
Other ingredients include: microcrystalline cellulose,
sodium stearyl fumarate, croscarmellose sodium,
colloidal anhydrous silica, polyoxyethylene stearate,
hypromellose and titanium dioxide (E171).

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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.