Losartan

In Aotearoa New Zealand losartan is available as tablets, which come in different strengths: 12.5 mg, 25 mg, 50 mg and 100 mg. Losartan is also available as a combination tablet with hydrochlorothiazide. For more information see losartan plus hydrochlorothiazide. 

• The dose of losartan will be different for different people. Your dose of losartan will depend on what it is being used for. Your doctor will tell you the dose that is right for you.
• Your doctor will usually start you on a low dose and increase the dose depending on how you respond. This allows your body to get used to the medicine and reduces side effects.
• Always take your losartan exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much losartan to take, how often to take it, and any special instructions.

• Timing: Take your dose at about the same time each day. You can take losartan with or without food.
• Stay hydrated and make sure you drink enough water. This is especially important during exercise and hot weather, which can increase your risk of dehydration. If you do not drink enough water you may feel faint, light-headed or sick. 
• Limit alcohol while taking losartan. Having the occasional drink while you are taking losartan is safe. However, regularly drinking excessive amounts increase your chance of side effects and reduce the effects of losartan.
• Missed dose: If you forget to take your dose, take it as soon as you remember that day. But if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.

Here are some things to know when you're taking losartan. Other things may be important as well, so ask your healthcare provider what you should know about.

Other medicines

Losartan interacts with some medications, herbal supplements and rongoā Māori, so check with your doctor or pharmacist before starting losartan and before starting any new products.

Be careful when taking pain relief medicines

Check with your healthcare provider before taking anti-inflammatory pain relief medication such as ibuprofen, while you are taking losartan. This combination can be very harmful to your kidneys and can cause acute kidney injury. You have a higher risk of harming your kidneys if you are taking diuretics (water pills), if you are elderly or if you are dehydrated. Ask your doctor or pharmacist for a safer pain relief options. Read more about NSAIDs and protecting your kidneys.

Have a sick day plan

If you have diarrhoea and/or vomiting from a stomach bug, or have dehydration from other causes, it’s important to let your doctor know. They may advise you to stop taking losartan for a few days and restart when you feel better. The reason for this is that this medicine can increase the level of potassium salts in your blood, particularly if you are dehydrated.

Pregnant or planning a pregnancy

Do not take losartan if you are pregnant, or if there is a chance you could become pregnant. Losartan can cause birth defects and is harmful to unborn babies. Talk to your healthcare provider about alternative blood pressure medicines.

Like all medicines, losartan can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.