Cetirizine is a non-drowsy antihistamine designed to effectively relieve the symptoms of allergies, such as hay fever, pet allergies, and skin rashes. It works by blocking the action of histamine, a natural substance in the body that causes allergic reactions. Suitable for adults and children over 6 years old, Cetirizine provides long-lasting relief from symptoms like sneezing, itchy eyes, and runny nose, allowing you to go about your day without discomfort. Available in convenient 10mg tablets or 5mg/5ml oral solution, it’s a reliable choice for managing mild to moderate allergies.
Dr Sarah Thornton MbChB, Coaching Academy diploma with distinction
GP, Medical coach
What is Cetirizine?
Cetirizine hydrochloride is the active ingredient in this medicine, known as an antihistamine, which helps to alleviate the uncomfortable symptoms of allergies. Cetirizine Hydrochloride 10mg Tablets are effective in treating hay fever and other allergic conditions, such as sneezing, a runny or itchy nose, and skin rashes (chronic nettle rash, idiopathic urticaria). This medicine is suitable for adults and children aged 2 years and older. Unlike older antihistamines, cetirizine is a non-drowsy option, allowing you to carry on with your day without feeling sleepy.
What is the active ingredient in Cetirizine?
Each tablet contains 10mg of cetirizine hydrochloride (the active ingredient).
What is Cetirizine used for?
Cetirizine is an antihistamine used to relieve the symptoms of allergies, such as:
Hay Fever (Allergic Rhinitis): Symptoms include sneezing, runny or itchy nose, and itchy or watery eyes.
Skin Allergies (Urticaria): This includes chronic idiopathic urticaria, where the skin develops itchy rashes, hives, or welts.
Other Allergic Reactions: Cetirizine can also be used to alleviate symptoms from reactions to pet dander, dust mites, and certain foods.
Cetirizine is a non-drowsy antihistamine, making it suitable for use during the day, allowing individuals to continue their daily activities without feeling overly sleepy.
How does Cetirizine work?
Cetirizine works by blocking the action of histamine, a chemical in the body that is released during an allergic reaction. When you come into contact with an allergen (like pollen, pet dander, or dust mites), your body releases histamine, which binds to receptors in certain cells, leading to symptoms such as itching, swelling, redness, and a runny nose.
Cetirizine is an antihistamine, which means it prevents histamine from binding to its receptors, thereby reducing or preventing the allergic symptoms from developing. By inhibiting this process, cetirizine helps relieve the discomfort associated with allergies, such as sneezing, runny nose, itchy eyes, and skin rashes. It is effective in managing symptoms of hay fever, urticaria (hives), and other allergic reactions. Additionally, cetirizine is known as a non-drowsy antihistamine, meaning it is less likely to cause drowsiness compared to older antihistamines, allowing for more normal daily activities.
How do you take Cetirizine?
Cetirizine is for oral use and can be taken by both adults and children to relieve symptoms of mild to moderate allergies.
10mg Tablets:
Children aged 6-12 years: Take half a tablet twice a day.
Children and adults over 12 years: Take one tablet daily.
5 mg/5 ml Oral Solution:
Children aged 2-5 years: Take one 5 ml spoonful once a day or one 2.5 ml spoonful twice a day.
Children aged 6-11 years: Take two 5 ml spoonfuls once a day or one 5 ml spoonful twice a day.
Children and adults over 12 years: Take two 5 ml spoonfuls once a day.
For complete instructions on how to use Cetirizine, please refer to the Patient Information Leaflet included in the product packaging for either Cetirizine 10 mg tablets or 5 mg/5 ml oral solution.
If you take more than the recommended dose of Cetirizine, seek medical advice immediately, even if you do not feel any adverse effects.
Some possible side effects include:
Diarrhea
Confusion
Headache
Tiredness or dizziness
Restlessness
Tremors
Who should not take Cetirizine?
Do not take Cetirizine Hydrochloride Tablets:
If you are allergic to cetirizine hydrochloride, any of the ingredients in this medicine, please refer to the patient information leaflet, hydroxyzine, or any piperazine derivatives (closely related active substances in other medicines).
If you have end-stage kidney disease (severe renal failure requiring dialysis).
Warnings and precautions:
If you have kidney problems, consult your doctor for advice. You may need a lower dose, which your doctor will determine.
If you have difficulty passing urine (such as due to spinal cord issues, prostate problems, or bladder issues), ask your doctor for guidance.
If you have epilepsy or are at risk of convulsions, seek advice from your doctor before taking this medication.
If you are scheduled for allergy testing, consult your doctor about stopping Cetirizine Hydrochloride Tablets a few days before the test, as this medication may affect your results.
Children and Cetirizine Hydrochloride Tablets:
This medicine is not recommended for children under 6 years of age, as this formulation does not allow for appropriate dose adjustment.
Other medicines and Cetirizine Hydrochloride Tablets:
Inform your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines.
Cetirizine Hydrochloride Tablets with food, drink, and alcohol:
Food does not affect the absorption of Cetirizine Hydrochloride Tablets.
No clinically significant interactions have been observed between alcohol (at a blood level of 0.5 g/l, equivalent to one glass of wine) and cetirizine at the recommended doses. However, since there are no data available on the safety of taking higher doses of cetirizine with alcohol, it is recommended to avoid alcohol while taking this medication.
Pregnancy and breast-feeding:
If you are pregnant, breastfeeding, think you may be pregnant, or are planning to have a baby, consult your doctor before taking this medicine.
Cetirizine Hydrochloride Tablets should generally be avoided during pregnancy. Accidental use during pregnancy is unlikely to harm the fetus, but the medication should only be taken if necessary and after medical consultation.
Cetirizine passes into breast milk, and there is a potential risk of side effects in breastfed infants. Therefore, you should not take Cetirizine Hydrochloride Tablets while breastfeeding unless advised by a doctor.
Driving and using machines:
Clinical studies have shown no evidence of impaired attention, alertness, or driving abilities after taking Cetirizine Hydrochloride Tablets at the recommended dose. However, you should carefully monitor how you respond to the medication if you plan to drive, engage in potentially hazardous activities, or operate machinery. It is important not to exceed the recommended dose.
Cetirizine Hydrochloride Tablets contain lactose:
If your doctor has informed you that you have an intolerance to certain sugars, consult your doctor before taking these tablets.
What are the side effects of Cetirizine?
Like all medicines, this one can cause side effects, although not everyone will experience them.
The following side effects are rare or very rare, but you must stop taking the tablets and consult your doctor immediately if you notice them:
Allergic reactions, including severe reactions and angioedema (a serious allergic reaction causing swelling of the face or throat). These reactions can occur soon after taking the medicine or may develop later.
Common side effects (may affect up to 1 in 10 people):
Somnolence (sleepiness)
Dizziness, headache
Diarrhea, nausea, dry mouth
Fatigue
Pharyngitis, cold-like symptoms of the nose (in children only)
Uncommon side effects (may affect up to 1 in 100 people):
Feeling agitated
Paresthesia (abnormal sensations in the skin)
Abdominal pain
Pruritus (itchy skin), rash
Asthenia (extreme fatigue), malaise (general feeling of unwellness)
Rare side effects (may affect up to 1 in 1,000 people):
Depression, hallucinations (seeing or hearing things), aggression, confusion, insomnia
Convulsions
Tachycardia (rapid heartbeat)
Abnormal liver function
Urticaria (hives)
Edema (generalized swelling due to water retention)
Weight gain
Very rare side effects (may affect up to 1 in 10,000 people):
Low blood platelet levels, leading to unusual bleeding or bruising
Side effects with unknown frequency (frequency cannot be estimated from the available data) may include:
Increased appetite
Memory loss or forgetfulness
Vertigo (a sensation of spinning or movement)
Urinary retention (difficulty in completely emptying the bladder)
Pruritus (intense itching) and/or urticaria (hives) upon discontinuation
Hepatitis (inflammation of the liver)
Arthralgia (joint pain), myalgia (muscle pain)
Acute generalized exanthematous pustulosis (a rash with pus-filled blisters)
Suicidal ideation (recurring thoughts of or preoccupation with suicide), nightmares
Reporting of side effects
If you experience any side effects, talk to your doctor, pharmacist, or nurse. This includes any potential side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
By reporting side effects, you can help provide more information on the safety of this medicine.
Does Cetirizine interact with any other medicines?
Betahistine
Cetirizine may reduce the effectiveness of Betahistine. The manufacturer does not provide a specific recommendation for this interaction.
Severity: Moderate
Evidence: Theoretical
Isocarboxazid
When combined with Cetirizine, Isocarboxazid may increase the risk of antimuscarinic side effects. The manufacturer advises against using these medications together.
Severity: Severe
Evidence: Theoretical
Phenelzine
Phenelzine, when taken with Cetirizine, may raise the risk of antimuscarinic side effects. The manufacturer advises avoiding this combination.
Severity: Severe
Evidence: Theoretical
Tranylcypromine
Tranylcypromine, in combination with Cetirizine, may increase the likelihood of antimuscarinic side effects. The manufacturer recommends avoiding this combination.
Severity: Severe
Evidence: Theoretical
Frequently asked questions
What is Cetirizine?
Cetirizine hydrochloride is an active ingredient known as an antihistamine, commonly used to alleviate the symptoms of allergies. This medicine is suitable for use in treating children from the age of 2 years old and is a non-drowsy option, allowing you to manage your allergies without feeling sleepy.
What is Cetirizine used for?
Cetirizine effectively relieves symptoms of allergies triggered by substances like pollen, pet fur, dust mites, insect bites or stings, and laundry detergents. Symptoms that Cetirizine helps reduce include:
Inflammation in your nose and eyes
Sneezing and watery eyes
Itchy skin rashes
How does Cetirizine work?
Cetirizine works by blocking the action of histamine, a chemical produced in the body that causes allergic reactions. As a non-drowsy antihistamine, it typically does not affect the brain as older antihistamines do, allowing you to remain alert. Cetirizine provides relief for around 24 hours and has a half-life of about 10 hours, gradually being eliminated by the kidneys and excreted in urine.
Loratadine vs Cetirizine
Loratadine and Cetirizine are both second-generation, non-drowsy antihistamines. They work similarly to reduce the symptoms of mild to moderate allergic reactions. However, Loratadine may cause nervousness and disturbed sleep in some people, while Cetirizine is more likely to cause drowsiness.
Can you take Cetirizine and Loratadine together?
It is not recommended to take more than one antihistamine within a 24-hour period unless advised by a doctor. If managing your symptoms with Cetirizine alone is not sufficient, consult a pharmacist or doctor for further advice.
Fexofenadine vs Cetirizine
Fexofenadine is another non-drowsy antihistamine used to treat allergies in children and adults over the age of 6 years. Unlike Cetirizine, Fexofenadine is only available by prescription and is typically used when Cetirizine and Loratadine are not effective or tolerated.
Cetirizine and alcohol
Alcohol can interact with antihistamines and increase the likelihood of drowsiness. It is advisable to limit alcohol consumption while taking Cetirizine.
Does Cetirizine make you drowsy?
Cetirizine is classified as a non-drowsy antihistamine, meaning it is less likely to cause drowsiness compared to older antihistamines. However, in some cases, it may cause sleepiness. It is recommended to see how Cetirizine affects you before driving or operating heavy machinery.
Children’s Cetirizine
Cetirizine is available in tablet form for children over six years old and as an oral solution for children over two years old. For dosage instructions, please refer to the product packaging or consult a healthcare professional.
Cetirizine warnings
Before taking Cetirizine, ensure you are aware of all associated warnings and precautions. Do not take Cetirizine if you have liver or kidney problems or are allergic to any of the ingredients. Consult a doctor before use if you suffer from urinary retention or epilepsy or are taking any other medications. Avoid alcohol as it may enhance the effects of drowsiness and dizziness.
Cetirizine and pregnancy
Cetirizine should not be taken during pregnancy or while breastfeeding without consulting a healthcare professional, as it can pass through breast milk and may affect the baby.
Cetirizine hydrochloride dosage
Cetirizine is for oral use only and can be taken by adults and children to treat mild to moderate allergies.
10mg Tablets:
Children 6-12 years: Half a tablet twice a day
Children and adults over 12 years: One tablet daily
5mg/5ml Oral Solution:
Children 2-5 years: One 5ml spoonful once a day or one 2.5ml spoonful twice a day
Children 6-11 years: Two 5ml spoonfuls once a day or one 5ml spoonful twice a day
Children and adults over 12 years: Two 5ml spoonfuls once a day
If you exceed the recommended dose, seek medical advice immediately.
