Cetirizine 10 mg is an effective antihistamine used to relieve allergy symptoms like sneezing, runny nose, and itchy skin caused by allergic rhinitis and urticaria. It works by blocking histamine, the chemical responsible for allergic reactions, helping reduce discomfort quickly. Taken once daily as prescribed, it provides long-lasting relief without causing significant drowsiness. However, alcohol should be avoided as it may enhance drowsiness. 

While cetirizine is generally well-tolerated, some users may experience mild side effects like dizziness, fatigue, or headache. Patients with liver or kidney disease should consult a doctor before use, as dosage adjustments may be necessary. Store the medicine at room temperature, away from moisture and sunlight. In case of an overdose, seek medical attention immediately. 

Cetirizine 10 mg is an oral medicine belonging to the class of antihistamine medicines. It is used for following indications: 

1. To treat seasonal, and year-round allergic rhinitis 
2. To treat skin conditions identified by itchy, raised, red welts or swelling (Chronic urticaria) 

1. Take cetirizine exactly as prescribed by your doctor, regularly at the same time each day. 
2. Do not stop taking cetirizine without your doctor’s approval, even if you feel better. 
3. If you forget to take the medicine, take it as soon as you remember, unless it’s almost time for the next one, then just skip it. 

More Common

1. Fatigue 
2. Vomiting 
3. Headache 
4. Sleepiness 
5. Dizziness 
6. Constipation 
7. Tiredness 

Less Common

1. Breathing, troubled 
2. Back, leg, or stomach pain 
3. Blurred vision 
4. Bloody, cloudy, or dark urine, sudden decrease in amount of urine 
5. Black, tarry stools, diarrhea, light-colored stools 
6. Confusion 
7. Dizziness, feeling faint, or lightheaded 
8. Fever or chills 
9. Increased blood pressure 
10. Rapid weight gain 
11. Skin rash or hives 
12. Swelling of face, mouth, throat, fingers, glands, feet, and/or lower legs 
13. Stillbirth 
14. Twitching, twisting, or uncontrolled repetitive movements of the face 
15. Sudden sweating 
16. Vomiting blood, bleeding gums, nosebleeds, unusual bleeding or bruising 
17. Pale or yellow eyes or skin 
18. Unusual tiredness or weakness 

Cetirizine works by inhibiting the release of a chemical called histamine, which is responsible for allergic reactions (itching, sneezing) and inflammation.  

1- Pregnancy and Breastfeeding

This medicine is not found in breast milk; therefore, it is considered safe. It also does not cause harm to the fetus and can be used during pregnancy.

2- Liver Disease

Patients with liver disease should not take a dose exceeding 5 mg per day.

3- Renal Disease

Doctors should not prescribe more than 5 mg of cetirizine per day to patients with renal disease.

Avoid taking cetirizine 10 mg with the following medicines, as it may increase or decrease the desired effect, or in worse cases, it could be fatal: 

Cetirizine does not interact with any food products, but alcohol should be avoided before and after taking Cetirizine, as it can increase or decrease it’s effect. 

1. The medicine should be stored at room temperature  
2. Keep away from sunlight and moisture  
3. Keep away from the reach of children 

IUPAC (International Union of Pure and Applied Chemistry)/ Chemical name- 

2-[4-[(4-chlorophenyl)-phenylmethyl]piperazin-1-yl]ethoxy]acetic acid. 

Daily Dose

Take cetirizine exactly as your doctor recommends. The dose may change based on your condition and how well you respond. Do not take more than prescribed without consulting your doctor.

Missed Dose

If you forget to take your medicine, take the medication soon as you remember. If it’s nearly time for your next dose, skip the missed one and continue with your regular schedule. Always consult the doctor before making any changes to your dosage.

Overdose

Cetirizine should not be taken in doses exceeding 4 g per day. Symptoms of overdose include dilated pupils, increased heart rate, elevated body temperature, and hallucinations. If you know someone who is taking cetirizine and exhibits these symptoms, rush them to the hospital immediately.

1- Will cetirizine make you sleepy?

Yes, cetirizine can cause sleepiness, as drowsiness is one of its common side effects. However, compared to older antihistamines, Allegra (fexofenadine) is less likely to cause drowsiness. So, if you’re concerned about feeling sleepy, Allegra might be a better option for you.

2- Can cetirizine and paracetamol be taken together?

Yes, cetirizine can be taken with paracetamol, but you should only take this combination under the guidance of a doctor, as the appropriate dosage will be determined by them.

3- Can cetirizine be used for skin allergies?

Yes, cetirizine is often prescribed for skin allergies, such as idiopathic urticaria.

4- Can cetirizine be given to dogs?

Yes, cetirizine can be used in dogs to treat skin allergies, but it’s important to consult a veterinarian before giving it to your pet to ensure the correct dosage and safety.

1. NHS. Cetirizine: side effects, dosage, and usage [Internet]. London: National Health Service (NHS); 2023 [cited 2025 Jan 9]. Available from. 
2. PetMD. Cetirizine for dogs: uses, dosage, and side effects [Internet]. PetMD; 2023 [cited 2025 Jan 9]. Available from. 
3. Naqvi A, Patel P, Gerriets V. Cetirizine. [Updated 2024 May 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from. 
4. Mayo Clinic. Cetirizine and pseudoephedrine (oral route): description and uses [Internet]. Rochester (MN): Mayo Clinic; 2023 [cited 2025 Jan 9]. Available from.