Patient leaflet - Losartan Potassium 25 mg film-coated tablets
1. What Losartan Potassium Tablets is and what it is used for
Losartan belongs to a group of medicines known as angiotensin-II receptor antagonists. Angiotensin-II is a substance produced in the body which binds to receptors in blood vessels, causing them to tighten. This results in an increase in blood pressure. Losartan prevents the binding of angiotensin-II to these receptors, causing the blood vessels to relax which in turn lowers the blood pressure. Losartan slows the decrease of kidney function in patients with high blood pressure and type 2 diabetes.
Losartan Potassium is used
- to treat patients with high blood pressure (hypertension) in adults and in children and adolescents 6-18 years of age.
- to protect the kidney in hypertensive type 2 diabetic patients with laboratory evidence of impaired renal function and proteinuria ≥ 0.5 g per day (a condition in which urine contains an abnormal amount of protein).
- to treat patients with chronic heart failure when therapy with specific medicines called angiotensin-converting-enzyme inhibitors (ACE inhibitors, medicine used to lower high blood pressure) is not considered suitable by your doctor. If your heart failure has been stabilised with an ACE inhibitor you should not be switched to losartan.
in patients with high blood pressure and a thickening of the left ventricle, Losartan
potassium has been shown to decrease the risk of stroke (“LIFE indication”).
2. What you need to know before you take Losartan Potassium Tablets
Do not take Losartan Potassium Tablets:
- if you are allergic to losartan or to any of the other ingredients of this medicine (listed in section 6),
- if your liver function is severely impaired,
- if you are more than 3 months pregnant (It is also better to avoid Losartan Potassium tablets in early pregnancy – see Pregnancy),
- if you have diabetes or impaired kidney function and you are treated with a blood pressure lowering medicine containing aliskiren.
Warnings and precautions:
Talk to your doctor, pharmacist or nurse before taking Losartan Potassium tablets.
You must tell your doctor if you think you are (or might become) pregnant. Losartan Potassium tablet is not recommended in early pregnancy, and must not be taken if you are more than 3 months pregnant, as it may cause serious harm to your baby if used at that stage (see pregnancy section).
It is important to tell your doctor before taking Losartan Potassium Tablets:
- if you have had a history of angioedema (swelling of the face, lips, throat, and/or tongue) (see also section 4 ‘Possible side effects’),
- if you suffer from excessive vomiting or diarrhoea leading to an extreme loss of fluid and/or salt in your body,
- if you receive diuretics (medicines that increase the amount of water that you pass out through your kidneys) or are under dietary salt restriction leading to an extreme loss of fluid and salt in your body (see section 3 ‘Dosage in special patient groups’),
- if you are known to have narrowing or blockage of the blood vessels leading to your kidneys or if you have received a kidney transplant recently,
- if your liver function is impaired (see sections 2 “Do not take Losartan Potassium tablets” and 3 “Dosage in special patient groups”),
- if you 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 ß-blocker concomitantly,
- if you have problems with your heart valves or heart muscle,
- 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),
- if you 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),
if you are taking any of the following medicines used to treat high blood pressure:
- an ACE-inhibitor (for example enalapril, lisinopril, ramipril), in particular if you have diabetes-related kidney problems.
aliskiren
Your doctor may check your kidney function, blood pressure, and the amount of electrolytes (e.g. potassium) in your blood at regular intervals.
See also information under the heading
“Do not take Losartan Potassium Tablets”
normally advise you to stop taking Losartan Potassium Tablets before you become pregnant or as soon as you know you are pregnant and will advise you to take another medicine instead of Losartan Potassium Tablets.
Losartan Potassium Tablets is not
recommended in early pregnancy, and must not be taken when more than 3 months pregnant, as it may cause serious harm to your baby if used after the third month of pregnancy.
Breast-feeding
Tell your doctor if you are breast-feeding or about to start breast-feeding. Lorsartan is not recommended for mothers who are breast feeding, and your doctor may choose another treatment for you if you wish to breast-feed. Especially if your baby is a newborn, or born prematurely.
Ask your doctor or pharmacist for advice before taking this medicine.
Driving and using machines:
No studies on the effects on the ability to drive and use machines have been performed. Losartan Potassium Tablet is unlikely to affect your ability to drive or use machines. However, as with many other medicines used to treat high blood pressure, losartan may cause dizziness or drowsiness in some people. If you experience dizziness or drowsiness, you should consult your doctor before attempting such activities.
Important information about some of the ingredients of Losartan Potassium Tablets
This medicine contains lactose.
If you have been told by your doctor that you have an intolerance to some sugars (e.g. lactose), contact your doctor before taking this medicine.
3. How to take Losartan Potassium Tablets
Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure. Your doctor will decide on the appropriate dose of Losartan Potassium Tablets, depending on your condition and whether you are taking other medicines. It is important to continue taking Losartan Potassium Tablets for as long as your doctor prescribes it in order to maintain smooth control of your blood pressure.
Adult patients with High Blood Pressure
- Treatment usually starts with 50 mg losartan (one tablet of Losartan Potassium 50 mg) once a day.
- The maximal blood pressure lowering effect should be reached 3-6 weeks after beginning treatment. In some patients the dose may later be increased to 100 mg losartan (two tablets of Losartan Potassium 50 mg or one tablet of Losartan Potassium) once daily If you have the impression that the effect of losartan is too strong or too weak, please talk to your doctor or pharmacist.
Use in children and adolescents
Children below 6 years of age
Losartan Potassium tablets is not recommended for use in children under 6 years old, as it has not been shown to work in this age group.
Children aged 6 - 18 years old
The recommended starting dose in patients who weigh between 20 and 50kg is 0.7mg of losartan per kg of body weight administered
once a day (up to 25mg of Losartan).
- The doctor may increase the dose if blood pressure is not controlled.
- Other form(s) of this medicine may be more suitable for children; ask your doctor or pharmacist.
Adult patients with high blood pressure and type 2 diabetes
- Treatment usually starts with 50 mg losartan (one tablet of Losartan Potassium 50 mg) once a day.
- The dose may later be increased to 100 mg losartan (two tablets of Losartan Potassium 50 mg or one tablet of Losartan Potassium 100 mg) once daily depending on your blood pressure response.
Losartan 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).
Adult patients with Heart Failure
Treatment usually starts with 12.5 mg losartan (one tablet Losartan Potassium 12.5 mg) once a day. Generally, the dose should be increased weekly step-by-step (i.e., 12.5 mg daily during the first week, 25 mg daily during the second week, 50 mg daily during the third week, 100 mg daily during the fourth week, 150 mg daily during the fifth week) up to the maintenance dose as determined by your physician. A maximum dose of 150 mg losartan (for example, three tablets of Losartan Potassium 50 mg or one tablet each of Losartan Potassium 100 mg and Losartan Potassium 50 mg) once daily may be used.
In the treatment of heart failure, losartan is usually combined with a diuretic (medicine that increases the amount of water that you pass out through your kidneys) and/or digitalis (medicine that helps to make the heart stronger and more efficient) and/or a beta-blocker.
Dosage in special patient groups
The doctor may advise a lower dose, especially when starting treatment in certain patients such as those treated with diuretics in high doses, in patients with liver impairment, or in patients over the age of 75 years. The use of losartan is not recommended in patients with severe hepatic impairment (see section “Do not take Losartan Potassium tablets”).
Administration
The tablets should be swallowed whole with a glass of water. You should try to take your daily dose at about the same time each day. It is important that you continue to take Losartan Potassium Tablets until your doctor tells you otherwise.
If you take more Losartan Potassium Tablets than you should
If you accidentally take too many tablets, or a child swallows some, contact your doctor immediately. Symptoms of overdose are low blood pressure, increased heartbeat, possibly decreased heartbeat.
If you forget to take Losartan Potassium Tablets
If you accidentally miss a daily dose, just take the next dose as normal. Do not take a double dose to make up for a forgotten tablet.
If you stop taking Losartan Potassium Tablets
Do not discontinue the treatment without consulting your doctor even if you feel better. It is important that you take Losartan Potassium Tablets for as long as your doctor prescribes it.
If you have any further questions on the use of this medicine, ask your doctor, pharmacist or nurse.
4. Possible side effects
Like all medicines, this medicine can cause side effects, although not everybody gets them. If you experience the following, stop taking losartan tablets and tell your doctor immediately or go to the casualty department of your nearest hospital:
A severe allergic reaction (rash, itching, swelling of the face, lips, mouth or throat that may cause difficulty in swallowing or breathing).
This is a serious but rare side effect, which affects more than 1 out of 10,000 patients but fewer than 1 out of 1,000 patients. You may need urgent medical attention or hospitalisation.
The following side effects have been reported with Losartan Potassium Tablets:
Common (may affect up to 1 in 10 people):
- dizziness,
- low blood pressure, (especially after excessive loss of water from the body within blood vessels e.g. in patients with severe heart failure or under treatment with high dose diuretics),
- dose-related orthostatic effects such as lowering of blood pressure appearing when rising from a lying or sitting position.
- debility,
- fatigue,
- too little sugar in the blood (hypoglycaemia),
too much potassium in the blood
(hyperkalaemia).
- changes in kidney function including kidney failure,
- reduced number of red blood cells (anaemia),
- increase in blood urea, serum creatinine and serum potassium in patients with heart failure.
Uncommon (may affect up to 1 in 100 people):
- somnolence,
- headache,
- sleep disorders,
- feeling of increased heart rate (palpitations),
- severe chest pain (angina pectoris),
- shortness of breath (dyspnoea),
- abdominal pain,
- obstipation,
- diarrhoea,
- nausea,
- vomiting,
- hives (urticaria),
- itching (pruritus),
- rash,
- localised swelling (oedema),
- cough.
Rare (may affect up to 1 in 1000 people):
- hypersensitivity
- angioedema
- inflammation of blood vessels (vasculitis including Henoch-Schönlein purpura),
numbness or tingling sensation
(paraesthesia),
- fainting (syncope),
- very rapid and irregular heartbeat (atrial fibrillation),
35 mm
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50 mg / 100 mg
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50 mg / 100 mg
- brain attack (stroke),
- inflammation of the liver (hepatitis),
- elevated blood alanine aminotransferase (ALT) levels, usually resolved upon discontinuation of treatment
- intestinal angioedema: a swelling in the gut presenting with symptoms like abdominal pain, nausea, vomiting and diarrhoea.
Not known (frequency cannot be estimated from the available data):
- reduced number of thrombocytes,
- migraine,
- liver function abnormalities,
- muscle and joint pain,
- flu-like symptoms,
- back pain and urinary tract infection,
increased sensitivity to the sun
(photosensitivity),
- unexplained muscle pain with dark (tea-coloured) urine (rhabdomyolysis),
- impotence,
- inflammation of the pancreas (pancreatitis),
low levels of sodium in the blood
(hyponatraemia),
- depression,
- generally feeling unwell (malaise),
- ringing, buzzing, roaring, or clicking in the ears (tinnitus),
- disturbed taste (dysgeusia).
Side effects in children are similar to those seen in adults.
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 Website:
www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
By reporting side effects you can help provide more information on the safety of this medicine.
5. How to store Losartan Potassium Tablets
- Keep this medicine out of the sight and reach of children
- Do not use this medicine after the expiry date, which is stated on the carton (EXP). The expiry date refers to the last day of that month.
- Do not store above 25°C. Store in the original package in order to protect from moisture.
- 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 protect the environment.
6. Contents of the pack and other information
What Losartan Potassium Tablets contains:
The active substance is losartan potassium. For 25mg: Each film-coated tablet contains 25 mg of losartan potassium, equivalent to 22.9mg of losartan.
For 50mg: Each film-coated tablet contains 50 mg of losartan potassium, equivalent to 45.8mg of losartan.
For 100mg: Each film-coated tablet contains 100 mg of losartan potassium, equivalent to 91.7mg of losartan.
The other ingredients are:
Core tablet: Lactose, pregelatinised maize starch, povidone K-90 (E1201), colloidal anhydrous silica (E551), talc (E553b),
magnesium stearate (E572).
Coating materials: Hyprolose (E463), hypromellose (E464), polyethylene glycol 400, titanium dioxide (E171), talc (E553b).
What Losartan Potassium Tablets looks like and content of the pack:
Losartan Potassium Tablets 25mg: White to off white, round, biconvex, film coated tablets with breakline on one side and “25” debossing on other side.
The break line is only to facilitate breaking for ease of swallowing and not to divide into equal doses
Losartan Potassium Tablets 50mg: White to off white, round, biconvex, film coated tablets with breakline on one side and “50” debossing on other side.
The break line is only to facilitate breaking for ease of swallowing and not to divide into equal doses
Losartan Potassium Tablets 100mg: White to off white, round, biconvex, film coated tablets plain on one side and “100” debossing on other side.
Losartan Potassium Tablets are packed in clear 250µ polyvinyl chloride (PVC) film coated with 90-gsm polyvinylidene chloride (PVdC) and plain 25µ aluminium blister foil and HDPE bottle pack.
Pack sizes:
Blister pack: 21, 28, 30, 90 or 98 tablets HDPE bottle pack for 50mg & 100mg: 250’s, 500’s and 1000’s (for hospital use only)
Not all pack sizes may be marketed
Marketing Authorisation Holder:
Accord Healthcare Limited
Sage House,
319, Pinner Road,
North Harrow,
Middlesex, HA1 4HF,
United Kingdom
Manufacturer:
Accord Healthcare Limited
Sage House,
319, Pinner Road,
North Harrow,
Middlesex, HA1 4HF,
United Kingdom
Accord Healthcare Polska Sp.z o.o., ul. Lutomierska 50,95-200 Pabianice, Poland
This leaflet was last revised in January 2026.
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- if you are taking other medications that may increase serum potassium (see section 2 “Other medicines and Losartan Potassium Tablets”)
- if you experience abdominal pain, nausea, vomiting or diarrhoea after taking Losartan Potassium Tablets. Your doctor will decide on further treatment. Do not stop taking Losartan Potassium Tablets on your own.
Children and adolescents
Losartan Potassium Tablets have been studied in children. For more information, talk to your doctor.
Losartan Potassium Tablets is not
recommended for use in children suffering from kidney or liver problems, as limited data are available in these patient groups. Losartan Potassium Tablets is not recommended for use in children under 6 years old, as it has not been shown to work in this age group.
Other medicines and Losartan Potassium Tablets:
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines.
Tell your doctor if you are taking potassium supplements, potassium-containing salt substitutes, potassium-sparing medicines such as certain diuretics (amiloride, triamteren, spironolactone), or other medicines that may increase serum potassium (e.g., heparin, trimethoprim-containing medicines), as the combination with Losartan Potassium Tablets is not advisable.
Take particular care if you are taking the following medicines while under treatment with Losartan Potassium:
- other blood pressure lowering medicines as they may additionally reduce your blood pressure. Blood pressure may also be lowered by one of the following drugs/ class of drugs: tricyclic antidepressants, antipsychotics, baclofen, amifostine,
- non-steroidal anti-inflammatory drugs such as indomethacin, including cox-2-inhibitors (medicines that reduce inflammation, and can be used to help relieve pain) as they may reduce the blood pressure lowering effect of losartan.
If your kidney function is impaired, the concomitant use of these medicines may lead to a worsening of the kidney function.
Lithium containing medicines should not be taken in combination with losartan without close supervision by your doctor. Special precautionary measures (e.g. blood tests) may be appropriate.
Your doctor may need to change your dose and/ or to take other precautions:
If you are taking an ACE-inhibitor or aliskiren (see also information under the headings “Do not take Losartan Potassium Tablets” and “Warnings and precautions”.
Losartan Potassium Tablets with food and drink:
Losartan Potassium Tablets may be taken with or without food.
Grapefruit juice should be avoided while taking Losartan Potassium Tablets
Pregnancy and breast-feeding:
Pregnancy
You must tell your doctor if you think you are (or might become) pregnant. Your doctor will