The active ingredient cetirizine belongs to the group of antihistamines and is primarily used to treat allergic symptoms such as hay fever. It is usually administered in the form of tablets, but can also be taken as a juice or drops. The most common side effects of cetirizine include headache and dry mouth.
Help for allergic reactions
Cetirizine is an antiallergic drug used to treat allergic skin reactions, atopic dermatitis, hives, and itching. In addition, the active ingredient can also help relieve symptoms of conjunctivitis caused by allergies. Cetirizine is also used to treat allergic asthma and hay fever. The typical symptoms of hay fever, such as itchy eyes and a blocked nose, are caused by histamine, which is released in the body during an allergic reaction. Cetirizine ensures that the action of histamine in the body is inhibited by blocking the binding sites for histamine (H1 receptors).
Side effects of cetirizine
Cetirizine belongs to the so-called second-generation antihistamines, which also include, for example, the active ingredients acrivastine, loratadine, and mizolastine. In contrast to the first-generation antihistamines, these active ingredients do not reach the central nervous system, or only in very small quantities, and thus have hardly any effects there. As a result, side effects such as fatigue occur only rarely – in about one in 100 patients. In addition to fatigue, side effects such as headache, dry mouth and drowsiness can also be triggered by taking cetirizine. Occasionally, nausea, abdominal pain, diarrhea, and dizziness and malaise may also occur. In addition, the use of the active ingredient is also said to cause cardiac arrhythmias in rare cases. Also rather rare can occur side effects such as sleep and movement disorders, difficulty breathing and swallowing, and problems focusing the eyes. In the event of an overdose of the active substance, the aforementioned side effects may be intensified. If in doubt, ask your doctor for advice in case of overdose.
Dosage of cetirizine
In general, adults and children twelve years of age and older can take one tablet of cetirizine (10 milligrams) daily to relieve allergic symptoms. For children between the ages of two and twelve, half a tablet daily is recommended. Depending on their body weight, however, children can also take a whole tablet – spread over the day, for example. In adults, the dose can be increased to 20 milligrams for the treatment of allergy-related asthma-like conditions. However, you should always discuss the exact dosage of cetirizine with your treating doctor or a pharmacist. According to the package leaflet, allergy symptoms are relieved within one hour after taking one tablet. It is best to take the tablet in the evening before going to bed together with a glass of water. In addition to tablets, cetirizine is also available in the form of juice and drops. Juice and drops can be dosed better than tablets and are therefore particularly suitable for children.
Interactions and contraindications
In general, no interactions with other medications are expected when taking cetirizine. However, the active substance should better not be combined with alcohol – even if no interactions have been found so far. If food is taken at the same time, the absorption of the active substance is slowed down but not reduced. It should also be noted that many commercially available cetirizine preparations contain lactose (milk sugar) and are therefore not suitable for people who suffer from lactose intolerance. Cetirizine should not be taken if there is hypersensitivity to the active ingredient. Likewise, the antihistamine should not be used in cases of severe kidney disease or the dosage should be explicitly discussed with a doctor. In children under two years of age, the intake should also be clarified with a doctor. In general, however, cetirizine is not suitable for children under two. Before an allergy test (prick test) is carried out, the active substance should not be taken for three days so as not to falsify the results of the test.
Cetirizine during pregnancy
During pregnancy, cetirizine should only be taken in consultation with the attending physician. Because so far studies are missing, which prove the harmlessness of the antihistamine during pregnancy. For this reason, it is particularly advisable not to use the active substance during the first three months of pregnancy. It is also not advisable to take it during breastfeeding, as the active ingredient can pass into breast milk and negative effects on the infant cannot be ruled out. If cetirizine is used, breastfeeding should be done beforehand.
