Senna

Senna

What it's for

Senna

How it's used (previously Dosage and administration)

Senna

Side effects

Senna

Who it's for

Senna

Interactions

Senna is a type of medicine called a stimulant laxative. It's used to treat constipation (problems pooing).

Senna comes as tablets or a liquid that you swallow. Follow the instructions that come with your medicine.

Side effects of senna include stomach pain, cramps or discomfort, and diarrhoea. More serious side effects are rare.

Senna is suitable for most adults and children aged 12 years and over, but always check before taking it because it's not suitable for everyone.

Taking senna with some medicines, remedies or supplements may cause problems. Always check before taking it.

What senna is for

Senna is used to treat constipation (problems pooing), such as not pooing very often or having poo that's dry and hard.

Senna is a type of medicine called a stimulant laxative. It works by triggering your bowel muscles to push poo out.

How to take senna

Senna comes as tablets or a liquid (syrup) that you swallow.

You take it once a day, usually in the evening before bed. It takes around 8 to 12 hours to work.

When taking senna:

• start with the lowest dose and increase it gradually if this does not work – speak to a doctor or pharmacist if you're not sure how much to take
• swallow tablets whole, with a drink of water
• use the spoon or cup that comes with the liquid medicine to measure the correct dose

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.

Important

See a doctor for advice if you've taken senna for 3 days and your symptoms have not improved or have got worse.

Do not take senna for more than 7 days unless a doctor or pharmacist has advised you to.

If you miss a dose of senna

If you forget to take a dose of senna, skip the dose you missed and take your next dose at the usual time.

Do not take 2 doses to make up for a missed dose.

If you take too much senna

Taking an extra dose of senna is unlikely to cause problems, but it's important to get medical advice if you take too much and feel unwell.

Speak to a pharmacist as soon as possible if:

• you've taken more senna than it says on the packet, leaflet or prescription and have symptoms such as being sick (vomiting), diarrhoea or stomach pain, or you feel dizzy and weak

If you're unable to speak to a pharmacist or you took too much of your medicine on purpose, call NHS 111 for advice.

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Side effects of senna

Like all medicines, senna can cause side effects, although not everyone gets them.

Possible side effects of senna include:

• stomach pain, cramps or discomfort
• diarrhoea
• yellow-brown or red-brown pee – this is harmless and will stop once you stop taking senna

Senna does not usually affect your ability to drive, ride a bike or use machinery.

Speak to a pharmacist or doctor if:

• you have any side effects that bother you or do not go away

They may be able to give you advice about how to reduce any side effects or may suggest reducing your dose.

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Serious side effects

Senna can sometimes cause serious side effects, although most of them are rare.

Possible serious side effects of senna include:

• an allergic reaction (anaphylaxis) – causing symptoms such as a swollen throat or tongue, a raised itchy rash and difficulty breathing
• low potassium in your blood – causing symptoms such as muscle weakness, tiredness, needing to pee a lot and heart rhythm problems (this can happen if you have frequent diarrhoea from taking senna for a long time)
• muscle spasms or swollen joints

Call 999 if:

• you're taking senna and think you might be having anaphylaxis

If you think you're having any other serious side effect, call NHS 111.

Who can and cannot take senna

Most adults and children aged 12 years and over can take senna. Children younger than 12 years can only have senna if it's prescribed by a doctor.

But senna is not suitable for everyone. For example, it may not be suitable if:

• you've had an allergic reaction or serious side effect from senna or another laxative before
• you have a bowel condition such as irritable bowel syndrome, diverticular disease or Crohn's disease, or a blockage in your bowel that is not from constipation
• have kidney or heart problems

Check the packet or leaflet that comes with your medicine to see if it's suitable for you or your child. Speak to a pharmacist or doctor if you're not sure if you can take it.

Breastfeeding and senna

You can take senna while breastfeeding, if your baby is aged 1 month or older.

It's rare for breastfed babies to get any side effects from medicine you're taking, but speak to a healthcare professional if you have any concerns about your baby.

Pregnancy and senna

You can usually take senna if you're pregnant, but it's best to speak to a pharmacist or doctor.

They may suggest making changes to your diet or lifestyle, or trying a different type of laxative first.

Taking senna with other medicines, food and drink

There are some medicines, remedies and supplements that may not mix well with senna.

This includes:

• some types of heart medicine, such as medicines for heart failure or heart rhythm problems
• medicines to make you pee more (diuretics)
• steroids
• anything made with liquorice root, such as supplements or liquorice tea

Before you take senna, check the packet or leaflet that comes with the medicine to see if it's suitable for you. Speak to a pharmacist or doctor if you're not sure if you can take it.

Food, drink and alcohol with senna

You can mostly eat and drink as normal while taking senna, but avoid anything made with liquorice root.