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Ranitidine

Also called Zantac®

Key points about ranitidine

Ranitidine is used short term in adults to treat indigestion and reflux.
In Aotearoa New Zealand ranitidine is commonly called Zantac®.
Find out how to take it safely and the possible side effects.

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Ranitidine is used to lower high levels of acid in your stomach which can cause conditions such as indigestion and reflux. It reduces the amount of acid produced in your stomach.

In Aotearoa New Zealand ranitidine is available as tablets (150 mg and 300 mg) that can be bought from your pharmacy without a prescription.

The usual dose of ranitidine is 150 mg, 1 or 2 times a day.

For some people, 150 mg once a day is enough but you may need a higher dose up to the maximum of 300 mg per day.

It’s best to take the lowest effective dose, for the shortest possible time.

Stop taking ranitidine after 14 days. If the symptoms return, or you don’t feel any better after taking ranitidine, talk to your healthcare provider to find out what’s causing your symptoms. There are usually other medicines you can try.

Take it whole: Swallow your tablet whole with a full glass of water. Don’t crush or chew it.
Timing: Take ranitidine as soon as you have symptoms. Ranitidine is usually taken once a day, but some people may need to take it 2 times a day. Follow the directions on the packaging.
Food: Ranitidine can be taken with or without food.
Missed dose: If you forget to take your dose, take it as soon as you remember. But if it’s nearly time for your next dose, just take the next dose at the usual time. Don’t take double the dose.

If any of the following apply to you, it's important to tell your healthcare provider before you start ranitidine:

You're under 12 years of age.
You're pregnant, could be pregnant, planning a pregnancy or breast-feeding.
You have problems with your kidneys.
You're taking any other medicines. This includes any medicines you are taking which you can buy without a prescription, as well as herbal and complementary medicines.

Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

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

The effects of ranitidine tablets are not immediate: It may take half an hour before you start to feel better but the effect will last between 12 to 24 hours.
Other medicines: Ranitidine interacts with some medicines, herbal supplements and rongoā Māori, so check with your healthcare provider before starting ranitidine and before starting any new products.
Indigestion medicines: If you also take indigestion remedies, take them at least 2 hours before or after you take your ranitidine.

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

Side effects	What should I do?
Stomach upset Feeling sick (nausea) Bloated Gas in the tummy Diarrhoea (runny poos) Constipation (hard to poo) Headache Feeling dizzy Feeling drowsy Confusion	These are common when you first start taking ranitidine and usually go way with time. If this medicine makes you dizzy or drowsy, don't drink alcohol and don't drive. Tell your healthcare provider if these continue or bother you.
Worsening stomach problems, such as really bad stomach pain, blood in your stool or black stools, vomiting blood or dark-coloured vomit Signs of liver problems such as dark urine, yellowing of the skin or eyes	Tell your healthcare provider immediately or phone Healthline 0800 611 116.
Signs of an allergic reaction such as skin rash, itches, swelling of the face, lips, mouth and tongue or problems breathing	This is rare. Stop taking ranitidine and phone 111 for an ambulance.