Tolterodine is a medicine used to treat symptoms of an overactive bladder. These can include:

• a sudden and urgent need to pee (urinary urgency)
• needing to pee more often than usual (urinary frequency)
• wetting yourself if you cannot make it to the loo in time (urinary incontinence)

It's also used to treat bedwetting in children (nocturnal enuresis).

Tolterodine works by relaxing the muscles around your bladder. This means your bladder can hold more liquid and you do not need to pee as often or as urgently.

Tolterodine is only available on prescription.

It comes as standard tablets and slow-release capsules (also called prolonged release or XL). This means the capsules release tolterodine slowly and evenly throughout the day.

• You’ll usually take tolterodine tablets twice a day or slow-release capsules once a day.
• Tolterodine may take at least 4 weeks to reach its full effect. If the symptoms do not improve after 1 to 2 weeks, talk to your doctor.
• Your doctor will check after 2 to 3 months that tolterodine is still working and is the best treatment for you.
• Your doctor will also review every 6 to 12 months whether your treatment is still needed.
• Common side effects of tolterodine include a dry mouth or headache.

Tolterodine can be taken by most adults. It can also be taken by children aged 2 years and over, on the advice of their specialist.

Tolterodine is not suitable for some people. To make sure it's safe for you, tell your doctor or pharmacist before starting tolterodine if you:

• have ever had an allergic reaction to tolterodine or any other medicine
• have kidney or liver problems
• have myasthenia gravis, a condition that causes muscle weakness
• have glaucoma
• are not able to pee or empty your bladder completely (urinary retention)
• have a severe stomach or bowel condition, including a rare complication of ulcerative colitis or Crohn's disease called toxic megacolon
• have problems digesting food, or have severe constipation
• have heart problems, including long QT syndrome, heart failure, irregular or slow heartbeats or cardiomyopathy
• have a hiatus hernia
• have nerve damage that affects blood pressure, heart rate, sweating, pooing, peeing and digestion (autonomic neuropathy)
• have digestive problems such as heartburn and acid reflux
• are pregnant, trying to get pregnant or breastfeeding

Always read the information that comes with your medicine.

Tolterodine capsules release the medicine evenly during the day. This means you do not need to take them as often as the standard tablets.

Swallow the tablets or capsules whole with a drink of water. Do not chew the capsules. You can take the tablets or capsules with or without food.

Dosage for tolterodine tablets

Adults will usually take 2mg in the morning and 2mg in the evening. Leave a gap of 12 hours between doses.

Children will usually take between 1mg and 4mg a day.

If you are giving tolterodine to a child to stop bedwetting, the usual dose is 1mg taken at bedtime. The dose can be increased up to a maximum of 2mg twice a day, depending on response.

If you have kidney or liver disease, or you're affected by side effects, your doctor may reduce your dose to 1mg twice a day.

Dosage for tolterodine slow-release capsules

The usual dose for adults taking slow-release tolterodine capsules is 4mg once a day.

Children will usually take between 1mg and 4mg a day.

If you have kidney or liver disease, or you're affected by side effects, your doctor may reduce your dose to 2mg once a day taken as tablets.

Take the capsule at the same time each day. This will help you to remember to take them.

What if I forget to take it?

If you forget to take a dose, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just skip the missed dose and take your next dose as normal.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you forget doses often, it may help to set an alarm to remind you. You could ask your pharmacist for advice on other ways to remember your medicines.

What if I take too much?

Taking 1 extra dose of tolterodine is unlikely to harm you.

However, you may get more side effects, such as a dry mouth or headache.

The amount of tolterodine that can lead to an overdose varies from person to person, and too much tolterodine can be dangerous.

Like all medicines, tolterodine can cause side effects, but not everyone gets them.

Common side effects

Keep taking tolterodine, but talk to your doctor or pharmacist if these side effects bother you or do not go away, or if you notice any other possible side effects.

Common side effects that may affect up to 1 in 10 people include:

• dry mouth
• headache
• feeling dizzy, sleepy, or a spinning sensation (vertigo)
• diarrhoea or being sick (vomiting)
• constipation
• farting and burping (wind)
• stomach pain
• dry eyes
• blurred vision
• problems or pain when peeing, and not being able to empty your bladder

Serious side effects

Serious side effects are rare.

Tell your doctor straight away if you have:

• stomach pain (especially after meals), feeling sick or being sick, a persistent urge to poo, not being able to poo or you have runny poos – these are all signs of faecal impaction, where large, hardened poo gets stuck and you cannot push it out
• difficulty fully emptying your bladder, or difficulty in starting to pee – these are signs of urinary retention, where pee builds up in your bladder because you're unable to pee
• high temperature or chills, burning sensation when peeing, pain in your back or side, or bloody or cloudy pee – these can be signs of a severe urinary tract infection (UTI)
• swollen ankles or legs (oedema) – where fluid builds up in your legs

What to do about:

• dry mouth – try chewing sugar-free gum or having sugar-free sweets. Having a dry mouth can cause tooth decay or a fungal infection. It also might stop medicine that you put under your tongue from dissolving properly, such as medicine for angina.
• headache – make sure you rest and drink plenty of fluids. Avoid alcohol. Ask your pharmacist to recommend a painkiller. Talk to your doctor if your headache is severe or lasts longer than 1 or 2 days.
• feeling dizzy, sleepy or a spinning sensation – do not drive, cycle, use tools, or operate machinery. Avoid drinking alcohol, as this may make your symptoms worse. Talk to your doctor if the dizziness or sleepiness bothers you.
• diarrhoea or being sick – drink lots of water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having strong-smelling pee. Do not take any other medicines without speaking to a pharmacist or doctor, if the effects last more than 1 or 2 days.
• constipation – eat more high-fibre foods, such as fresh fruit and vegetables and cereals, and drink plenty of water. Try to exercise more regularly, for example, by going for a daily walk or run. If this does not help, talk to a pharmacist or doctor. Watch this short video about how to treat constipation.
• farting and burping – eat less foods that cause wind, like lentils, peas, beans and onions. It might also help to eat smaller and more frequent meals, eat and drink slowly, and exercise regularly. Ask your pharmacist about remedies you can buy to help with trapped wind.
• stomach pain – try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Try putting a heat pad or a covered hot water bottle on your stomach to help. If you are in a lot of sudden severe pain, speak to your pharmacist or doctor.
• dry eyes – ask your pharmacist or optician to recommend some eye drops. If you wear contact lenses and these become uncomfortable, you might have to wear glasses instead while you're taking this medicine.
• blurred vision – do not drive or ride a bike until you can see clearly again. Do not take your next dose of tolterodine if your vision is still blurred. Speak to your doctor or pharmacist if your vision has not returned to normal a day after taking your last dose.
• problems or pain when peeing – try to relax when you pee. Do not try to force the flow of urine. If it does not happen, try again later. Talk to a doctor urgently if you cannot pee at all

Tolterodine is not usually recommended in pregnancy because there's not enough information available to say it's safe for you and your baby.

If you're trying to get pregnant or you're already pregnant, talk to your doctor about whether taking tolterodine is right for you.

Tolterodine and breastfeeding

Tolterodine is not usually recommended while breastfeeding. However, some breastfeeding mothers may still need it.

It is not known how much tolterodine gets into breast milk, but this is likely to be small.

If your doctor says it's OK for you to keep taking tolterodine, monitor your baby for possible side effects, such as constipation, peeing less and colic.

Talk to your doctor, midwife, or health visitor if you have any concerns about your baby while you're breastfeeding, including if you do not think your baby is putting on enough weight.

For more information about treating bladder problems (urinary incontinence) during pregnancy, read this leaflet on the Best Use of Medicines in Pregnancy (BUMPs) website.

Some medicines and tolterodine can affect each other. This can increase the chance of side effects.

Tell your doctor if you're taking:

• antibiotics like erythromycin or clarithromycin
• ketoconazole or itraconazole, which are used to treat fungal infections
• medicines used to treat HIV
• metoclopramide, used to increase how quickly you digest food
• amiodarone, sotalol, quinidine or procainamide, which are used to treat irregular heartbeats
• other medicines that work in a similar way to tolterodine, such as amantadine

Mixing tolterodine with herbal remedies and supplements

There might be a problem using herbal remedies and supplements while taking tolterodine.

Some herbal medicines can make you feel sleepy, cause a dry mouth, or make it difficult to pee. Their effect is similar to tolterodine. This can increase your risk of getting side effects or make your side effects worse.