Cetirizine is a commonly used antihistamine in Australia, widely prescribed to relieve allergy symptoms such as hay fever, allergic rhinitis, and chronic hives. While cetirizine is generally well tolerated, like all medications, it can cause side effects. Understanding these potential effects helps users take the medicine safely and know when to seek medical advice.
Common Side Effects of Cetirizine
The most frequently reported side effects of cetirizine include:
- Drowsiness or fatigue: Although cetirizine is a second-generation antihistamine and less sedating than older antihistamines, some people may still feel sleepy or tired.
- Headache: Mild to moderate headaches are commonly reported.
- Dry mouth: A sensation of dryness in the mouth can occur.
- Gastrointestinal symptoms: These include nausea, stomach pain, vomiting, and diarrhea.
- Sore throat or cough: Some users experience throat irritation or coughing.
- Nosebleeds: Occasionally reported but less common.
- Irritability or trouble sleeping: Particularly in children, cetirizine may cause restlessness or difficulty falling asleep.
These side effects are usually mild and tend to improve as your body adjusts to the medication.
Less Common and Rare Side Effects
While uncommon, some users may experience:
- Dizziness or lightheadedness
- Increased sweating
- Altered taste or numbness/tingling sensations
- Skin reactions: Mild rash or itching
Rare but serious side effects include:
- Severe allergic reactions (anaphylaxis): Symptoms such as swelling of the face, lips, tongue, or throat, difficulty breathing, hives, or severe rash require immediate emergency care.
- Breathing difficulties: Cetirizine may rarely cause bronchospasm (tightening of the airways).
- Rapid heartbeat or swelling (edema): These are very rare but should prompt urgent medical attention.
When to Seek Medical Help
Stop taking cetirizine and seek immediate medical assistance if you experience:
- Swelling of the face, lips, tongue, or throat
- Difficulty breathing or wheezing
- Severe rash or hives
- Unexplained bruising or bleeding
- Persistent dizziness or fainting
For mild side effects that bother you or do not improve, consult your healthcare provider for advice.
Tips to Manage Side Effects
- Taking cetirizine in the evening may reduce daytime drowsiness.
- Stay hydrated and chew sugar-free gum to alleviate dry mouth.
- Rest and avoid driving or operating machinery if you feel dizzy or sleepy.
- Report any unusual or persistent symptoms to your doctor or pharmacist.
Summary
Cetirizine is a well-tolerated antihistamine widely used in Australia to manage allergy symptoms. Common side effects include drowsiness, headache, dry mouth, and mild gastrointestinal upset, which usually improve over time. Serious side effects are rare but require urgent medical attention. Always follow your healthcare provider’s instructions and report any concerning symptoms promptly.