Cetirizine

What is Cetirizine?

Cetirizine is an antihistamine which treats symptoms caused by allergies. It can be used to treat the effects of hayfever, insect bites or stings, conjunctivitis, eczema and hives. The medicine is taken as a tablet to deal with an allergic reaction. 

How does Cetirizine work?

Histamines are a chemical produced by your body when you come into contact with something you are allergic to. Histamine is what causes your symptoms, otherwise known as an allergic reaction, for example a blocked or runny nose, sneezing, itchy eyes or skin. Cetirizine is an antihistamine which prevents the histamine chemical from taking effect  in order to calm your symptoms. 

How long does Cetirizine take to work?

Cetirizine should start to work an hour after taking it.

Active ingredients

Cetirizine hydrochloride is the active ingredient in this antihistamine treatment.

Inactive ingredients

The other ingredients in Cetirizine are: lactose, microcrystalline cellulose, maize starch, colloidal anhydrous silica, magnesium stearate, talc, hypromellose, titanium dioxide (E171), macrogol4000 and sodium citrate.

Please Note: Different brands of generic Cetirizine may contain different inactive ingredients.

How to take Cetirizine

Always follow the instructions given by your doctor on how to take it. Swallow tablets whole with water or juice. If you are using the liquid version, use the measuring spoon to ensure you take the correct amount. For hay fever you may need to take Cetirizine everyday to prevent symptoms from occurring, otherwise you might only need it when you’ve been exposed to an allergy.

Cetirizine dosage

Cetirizine tablets come as a 10mg dose. A 5mg dose is available in liquid form which may be more suitable for children.

Cetirizine side effects

Common side effects that are associated with taking Cetrizine are: 

• Drowsiness
• Headaches
• Nausea
• Stomach pain
• Dry mouth
• Blocked or runny nose like you have the cold
• Agitation
• A tingling feeling in your hands and feet
• Diarrhoea 
• A rash or itchy skin 

If you experience any severe side effects, or the symptoms of an allergic reaction (e.g. hives, itching, breathing difficulties, swelling) you should seek immediate medical attention.

Contraindications

Cetirizine can usually be taken by adults and children over the age of six. However you shouldn’t take Cetirizine if:

• You are allergic to cetirizine or have experienced an allergic reaction to medicines in the past
• You are allergic to peanuts, soya, E218 or E216
• You have an intolerance to lactose or sorbitol
• You have kidney or liver failure
• You suffer from epilepsy or fits 
• You have difficulty urinating 
• You have a scheduled allergy test as Cetirizine can interfere with the results  

Drug interactions

If you are taking any other medications you should inform your doctor or pharmacist before you start Cetirizine. In particular the following medicines may interact with it: 

• Midodrine- which is taken for high blood pressure
• Ritonavir- which is a treatment for HIV
• Other medicines which have a drowsy effect or cause urination problems, including herbal remedies  

Is Cetirizine non-drowsy?

Cetirizine is a non-drowsy treatment so taking it shouldn’t make you feel tired or sleepy. In rare cases, some people may experience drowsiness as a side effect of Cetirizine. If so, you should avoid driving or operating machinery and you should speak to your doctor about alternative treatments?

Cetirizine and alcohol

It’s recommended to avoid alcohol while taking Cetirizine as it can cause you to become drowsy and feel tired. 

Cetirizine and pregnancy

Cetrizine is fine to take while you are pregnant but Loratadine is usually recommended instead as this similar medicine is proven to be safe to use during pregnancy. 

Can I drive after taking Cetirizine?

You should wait and see how Cetirizine affects you before driving. While it’s a non-drowsy treatment it can still cause drowsiness in some people.

Will Cetirizine affect my fertility?

Antihistamine medicines will not have an effect on your fertility. If you are trying to get pregnant then consult your doctor before taking Cetirizine. 

Will Cetirizine interfere with my contraception?

Your contraception will not be affected by Cetirizine. This includes all methods of hormonal contraception. However, you should always inform the prescribing doctor of any other medications you are taking. 

Can I take Cetirizine with pain killers?

Cetirizine can be taken alongside painkillers like Paracetamol and Ibuprofen. If you are taking prescription pain killers, you should check with your doctor before taking both medications together. 

How to cope with Cetirizine side effects

Avoiding excess alcohol and drinking enough water can help to manage headaches and a dry mouth. Check with a pharmacist to find a painkiller that’s suitable to take alongside Cetirizine. Sit still or lie down if you experience dizziness and avoid driving or operating machinery until this passes. For a sore throat or a runny nose, Aspirin and Ibuprofen can relieve these symptoms but Aspirin should not be used for anybody under 16. If Cetirizine makes you agitated then take it at night before bed.

How to avoid hay fever

Hay fever can be impossible to avoid at times but staying indoors on days which have a high pollen count will help. Other things you can do include avoiding cutting grass or walking on it, wearing sunglasses to protect your eyes from pollen and wash and change your clothes after being outside. Avoid having flowers inside your home and keep the windows closed. 

Prescription vs over the counter Cetirizine

Cetrizine is available on prescription in and it can also be purchased over the counter in reduced strengths. If you choose to get it on prescription then your doctor will be able to recommended the most suitable dose for your symptoms. This is particularly important for children as they need to calculate the right dose for them to take. 

Cetirizine vs other antihistamines

Cetirizine may be preferred to other traditional antihistamines as it is non-drowsy. This means it’s less likely to make you feel drowsy after taking it which may be more suitable to manage your day to day activities. Loratadine is another non-drowsy antihistamine medicine which has no drowsy effect at all but it may cause difficulty sleeping and can induce nervousness so it may not suit someone with anxiety problems.

Can I take Cetirizine with other antihistamines?

You should always take Cetirizine as instructed by your doctor or pharmacist. They may advise you that you will benefit from taking more than one antihistamine to keep your symptoms under control. You should only do this if your doctor has prescribed it. 

Are there any other uses for Cetirizine?

Cetirizine can also be used to relieve eczema, conjunctivitis, hives and insect bites or stings. 

Is long term use of Cetirizine safe?

You should only take Cetirizine when you have symptoms. Long term use is safe but if you are using it all the time then speak to your doctor so that they can assess your symptoms and suggest the most appropriate treatment.

Can Cetirizine be used for any other allergies?

Cetirizine is mainly used for hayfever but if you suffer from eczema, conjunctivitis or hives then the antihistamine will provide relief. It can also be used to treat itching caused by an insect bite or sting. 

Can Cetirizine be used for a cold?

Cetirizine is for treating the symptoms produced by an allergy. Even if this is similar to the symptoms of a cold, this medication is not suitable for treating the cold virus. 

Will Cetirizine help me sleep?

Cetirizine is non-drowsy so it won’t necessarily make you feel sleepy. However, if your symptoms are preventing you from being able to fall asleep, such as a blocked nose, then Cetirizine will help to relieve this and allow you to breathe with ease.

Is Cetirizine addictive?

Cetirizine is not known to be addictive. 

Sources

• Patient Information Leaflet
• NHS > Cetirizine
• MedicineNet > What are Cetirizine and Loratadine?