- It's usual to take fexofenadine once a day. Children sometimes take it twice a day.
- Fexofenadine is classed as a non-drowsy antihistamine, but some people still find it makes them feel quite sleepy.
- Common side effects include headaches, feeling sleepy, dry mouth, feeling sick and dizziness.
- Do not drink grapefruit juice, apple juice or orange juice while you're taking fexofenadine. It might make you more likely to get side effects.
- It's best not to drink alcohol while you're taking fexofenadine as it can make you feel sleepy.
- Fexofenadine is also called by the brand name Telfast.
Fexofenadine tablets can be taken by adults under the age of 65 and children aged 6 years and over.
Fexofenadine isn't recommended for people over 65 years old because there isn't much research on the medicine in this age group.
Talk to your pharmacist or doctor if you're over 65 and want to take fexofenadine.
Fexofenadine isn't suitable for some people. Tell your doctor or pharmacist if you:
- have had an allergic reaction to fexofenadine or any other medicines in the past
- have problems with your liver or kidneys
- have, or have ever had, heart problems
- have epilepsy or another health problem that puts you at risk of seizures
- are booked to have an allergy test - taking fexofenadine may affect the results, so you might need to stop taking it a few days before the test
If you or your child have been prescribed fexofenadine, follow your doctor's instructions about how and when to take it.
How much to take
Fexofenadine comes as tablets (30mg, 120mg and 180mg).
How much you take depends on why you're taking it:
- For hay fever - the usual dose for adults and children aged 12 years and over is 120mg once a day. The usual dose for children aged 6 to 11 years is 30mg twice a day. In this case, try to space the doses 10 to 12 hours apart.
- For hives - the usual dose for adults and children aged 12 years and over is 180mg once a day.
How to take it
If you're taking 30mg fexofenadine tablets, you can take them with or without food.
If you're taking 120mg and 180mg fexofenadine tablets, take them before a meal.
Always take your fexofenadine tablets with a drink of water. Swallow them whole - do not chew them.
When to take it
You may only need to take fexofenadine on a day you have symptoms, such as if you have been exposed to something you're allergic to, like animal hair.
Or you may need to take it regularly to prevent symptoms, such as to stop hay fever during spring and summer.
What if I forget to take it?
If you're taking fexofenadine once a day, do not take a double dose to make up for a forgotten dose. Take the next dose at the usual time as prescribed by your doctor.
If you forget doses often, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.
What if I take too much?
Fexofenadine is generally very safe. Taking too much is unlikely to harm you.
If you take an extra dose by mistake, you might get some of the common side effects. If this happens or you're concerned, contact your doctor.
Like all medicines, fexofenadine can cause side effects, although not everyone gets them.
Common side effects
Common side effects of fexofenadine happen in more than 1 in 100 people.
Talk to your doctor or pharmacist if these side effects bother you or don't go away:
- feeling sick (nausea)
- feeling sleepy
- dry mouth
- feeling dizzy
Serious side effects
It's rare to have a serious side effect with fexofenadine. Call a doctor straight away if you get a fast or irregular heartbeat.
Serious allergic reaction
In rare cases, fexofenadine may cause a serious allergic reaction (anaphylaxis).
Call 999 or go to A&E if:
- you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
- you're wheezing
- you get tightness in the chest or throat
- you have trouble breathing or talking
- your mouth, face, lips, tongue or throat start swelling
You could be having a serious allergic reaction and may need immediate treatment in hospital.
These are not all the side effects of fexofenadine. For a full list, see the leaflet inside your medicine packet.
You can report any suspected side effect to the UK safety scheme.
What to do about:
- feeling sick - stick to simple meals and do not eat rich or spicy food
- feeling sleepy - try a different non-drowsy antihistamine. If this doesn't help, talk to your doctor.
- headache - take an everyday painkiller like paracetamol or ibuprofen
- dry mouth - chew sugar-free gum or suck sugar-free sweets
- feeling dizzy - lie down until the dizziness passes, then get up slowly. Move slowly and carefully. Avoid coffee, cigarettes, alcohol and recreational drugs. If the dizziness doesn't get better within a couple of days, speak to your pharmacist or doctor.
Fexofenadine isn't normally recommended during pregnancy.
A similar antihistamine called loratadine is normally used first because there's more information to say that it's safe.
Talk to your doctor about the benefits and possible harms of taking fexofenadine. It'll also depend on how many weeks pregnant you are and the reason you need to take fexofenadine.
For more information about how fexofenadine can affect you and your baby during pregnancy, read this leaflet on the Best Use of Medicines in Pregnancy (BUMPS) website.
Fexofenadine and breastfeeding
There's not a lot of information on the use of fexofenadine during breastfeeding, so it's best not to take it.
But speak to your doctor before taking any antihistamine if your baby was premature, had a low birth weight, or has other health problems.
Tell your doctor if you're:
- trying to get pregnant
Some medicines and fexofenadine interfere with each other and increase the chances of you having side effects.
Check with your pharmacist or doctor if you're taking:
- midodrine, a medicine used to treat low blood pressure
- ketoconazole, a medicine to treat fungal infections
- erythromycin, an antibiotic
- ritonavir or lopinavir, medicines used to treat HIV infection
- rifampicin, an antibiotic
- indigestion remedies containing aluminium or magnesium - leave about 2 hours between the times that you take fexofenadine and your indigestion remedy
- any medicine that makes you drowsy, gives you a dry mouth, or makes it difficult for you to pee (taking fexofenadine might make these side effects worse)
Mixing fexofenadine with herbal remedies and supplements
There might be a problem taking some herbal remedies and supplements alongside fexofenadine, especially ones that cause sleepiness, a dry mouth, or make it difficult to pee.
Ask your pharmacist for advice.
Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.
How does fexofenadine work?
Fexofenadine is a medicine called an antihistamine.
When you come into contact with something you're allergic to, such as pollen, animal hair or fur, house dust, or insect bites and stings, your body produces a chemical called histamine.
Usually histamine is a useful substance, but in an allergic reaction it causes unpleasant symptoms including itchy, watery eyes, a running or blocked nose, sneezing and skin rashes.
Fexofenadine blocks the effects of histamine and reduces these symptoms.
When will I feel better?
You should start to feel better within an hour or two.
How long should I take fexofenadine for?
It depends on why you're taking fexofenadine.
You may only need to take it as a one-off dose or for a day or two - for example, if you have a reaction to an insect bite.
You may need to take fexofenadine for longer if you're taking it to prevent symptoms - for example, to stop hay fever when the pollen count is high.
Talk to your doctor or pharmacist if you're unsure how long you need to take fexofenadine for.
Is it safe to take fexofenadine for a long time?
Fexofenadine is unlikely to do you any harm if you take it for a long time. But it's best to take fexofenadine only for as long as you need to.
Can I drink alcohol with it?
It's best not to drink alcohol while you're taking fexofenadine as it can make you feel sleepy.
Is there any food or drink I need to avoid?
Do not drink grapefruit juice, orange juice or apple juice while taking fexofenadine. It might make you more likely to have side effects.
Can I drive or ride a bike with it?
Fexofenadine is classed as a non-drowsy antihistamine, but it's still possible to feel sleepy after taking it.
If you're taking fexofenadine for the first time, see how it makes you feel before driving, cycling, or using heavy machinery or tools.
Does fexofenadine cause weight gain?
Fexofenadine isn't known to cause weight gain.
What's the difference between fexofenadine and other antihistamines?
Fexofenadine is known as a non-drowsy antihistamine. That's because it's less likely to make you feel sleepy than so-called sedating antihistamines, such as Piriton (chlorphenamine).
Most people prefer to take a non-drowsy antihistamine instead of a sedating one.
An exception is when you want the medicine to make you sleepy - for example, if you have itchy skin that's keeping you awake.
What's the difference between fexofenadine and other non-drowsy antihistamines?
But fexofenadine seems to be less likely to make you feel sleepy than other non-drowsy antihistamines.
If one non-drowsy antihistamine hasn't worked for you, it's worth trying another one.
Why is fexofenadine only available on prescription?
For a medicine to become available to buy without a prescription, it has to be shown to be safe enough to use without the need to see a doctor.
Unlike some other antihistamines, fexofenadine hasn't been through this process yet.
Can I take it with painkillers?
Can I take more than 1 antihistamine together?
Sometimes doctors recommend that people with a severe itchy skin rash take 2 different antihistamines together for a few days.
As well as taking a non-drowsy antihistamine during the day (such as fexofenadine, cetirizine or loratadine), your doctor may suggest that you take a sedating antihistamine at night time if the itch is making it difficult to sleep.
Do not take 2 antihistamines together unless your doctor advises you to.
Can I take fexofenadine with other hay fever treatments?
Yes, it's fine to take fexofenadine together with other hay fever treatments - for example, steroid nasal sprays (such as Beconase, Rhinacort Aqua and Flixonase Nasules) or eye drops.
Can I take fexofenadine at higher doses than on the packet?
Your doctor might suggest you or your child take a higher dose of fexofenadine (up to 4 times the usual dose) for a severe itchy skin rash or swelling underneath the skin (angioedema).
Taking high doses of fexofenadine isn't suitable for everyone. Speak to your doctor if you don't think fexofenadine is working for you.
Will it affect my fertility?
There's no firm evidence to suggest that taking fexofenadine will reduce fertility in either men or women.
But speak to a pharmacist or your doctor before taking it if you're trying to get pregnant.
Will it affect my contraception?
Can lifestyle changes relieve hay fever?
It'll help if you don't spend too much time outside if the pollen count is high.
Tips for when you're outside
- Do not cut grass or walk on grass.
- Wear wraparound sunglasses to stop pollen getting into your eyes.
- Put Vaseline around your nostrils to help trap pollen.
- Shower and change your clothes after you have been outside to wash off pollen.
Tips for when you're inside
- Keep windows and doors shut as much as possible.
- Vacuum regularly and dust with a damp cloth.
- Do not keep fresh flowers in the house.
- Do not smoke or be around smoke as it makes hay fever symptoms worse.