Cetrizine is a prominent representative of the latest generation of antihistamines. Its action is characterized by a prolonged antiallergic effect[2].
Cetirizine is the active ingredient of the drug Cetrin®, which belongs to the group of effective second-generation histamine blockers. It is designed to effectively cope with many symptoms of allergic reactions (cough, itchy nose, rash and redness on the skin, lacrimation, photophobia, etc.)[1].
Cetirizine is synthesized as a crystalline white powder, easily soluble in water. Available in tablet form. The cardboard package contains 1 blister with 10 or 7 tablets, which contain 10 mg of active ingredient and a number of excipients (magnesium stearate, lactose monohydrate, titanium dioxide, colloidal silicon dioxide and others).
The drug helps relieve itching of the mucous membranes, reduce redness and lacrimation, cope with nasal congestion, and get rid of rhinorrhea and sneezing [1,2].
Composition and release form
The drug is available in the form of tablets and drops for oral administration.
The tablets have a special soluble coating. Packaged in paper packaging with attached instructions for use.
The drops are a light liquid. Sold in bottles of 10 or 20 ml.
The active ingredient is cetirizine dihydrochloride. Its content in tablets and drops is 10 mg.
Excipients: magnesium stearate, silicon dioxide, lactose in tablets. Also benzoic acid, glycerol, sodium acetate, propylene glycol and pure water in the form of drops.
pharmachologic effect
The medicine belongs to the pharmacological group of antiallergic drugs. The active components of the drug block H1 type histamine receptors, providing a pronounced antiexudative, antipruritic and decongestant effect.
There is a decrease in the permeability of the walls of blood vessels and capillaries, muscle spasms and skin reactions are stopped.
The drug does not exhibit sedative properties and almost does not cause anticholinergic effects.
The therapeutic effect is observed quickly, within an hour after application. Maximum after 4 hours and lasts throughout the day. After discontinuation of the drug, pharmacological activity is recorded for another 3 days. Addiction to Cetirizine does not develop.
Indications for use of cetirizine
Not all cetirizine-based drugs have the same indications for use. The maximum number of indications in Russia is registered for the drug Cetrin ®:
- seasonal and year-round allergic rhinitis;
- allergic conjunctivitis;
- hay fever (hay fever);
- urticaria (including chronic idiopathic);
- itchy allergic dermatoses (atopic dermatitis, neurodermatitis);
- angioedema (Quincke's edema) 2
Contraindications
Do not use an antihistamine in the following cases:
- The period of bearing a child.
- Breast-feeding.
- Children's age up to 6 years.
- Lactose intolerance and poor absorption.
- Kidney failure.
- Individual intolerance to drugs.
- Malalabsorption of glucose and galactose.
Cetirizine should be prescribed with caution to elderly people and those with serious kidney disease. Also for patients undergoing treatment with barbiturates, narcotic analgesics, and benzodiazepines.
special instructions
After taking the medicine, you should not drive a vehicle.
Interaction with Diazepam, Cimetidine and Azithromycin has not been established. Use with Theophylline leads to a decrease in drug clearance. Particular caution should be taken in parallel with medications that have a depressant effect on the central nervous system.
The product enhances the effect of alcohol, so you should avoid taking it. The medication must be taken 3 days before allergy testing.
You can buy it at a pharmacy without a doctor's prescription.
Store at room temperature. Shelf life – 36 months from the date of release.
Side effects
Taking an antihistamine may be accompanied by side effects. More common:
- Stool disorder.
- Excitement, nervousness.
- Asthenia.
- Skin rashes, itching, swelling.
- Parasthesia.
- The following side effects occur less frequently:
- Quincke's edema, urticaria.
- Urinary dysfunction.
- Increased body weight.
- Movement disorders.
- Drowsiness or insomnia.
- Loss of consciousness.
- Depression, aggression.
- Increased heart rate.
- Signs of hepatitis.
Side effects
After administration, the following negative reactions may occur:
- excited state;
- skin rashes;
- diarrhea;
- asthenia.
In rare cases it is possible:
- cardiopalmus;
- hepatitis;
- hives;
- dizziness (up to fainting);
- nervous system disorder;
- disturbed sleep;
- stress.
If you follow the instructions and do not exceed the dosage, then even with prolonged treatment the likelihood of adverse reactions is minimized.
Instructions for use
The dosage and duration of the course of Cetirizine depends on the age of the patient, diagnosis and dosage form of the drug.
The product in the form of drops is used according to the following scheme:
- Children 1-2 years old - 5 drops 2 times a day.
- Children 3-6 years old - 10 drops before bedtime.
- Patients 6-12 years old - no more than 20 drops in the evening.
- Children over 12 years of age and adults - 20 drops once.
For elderly people, the dosage is not changed. In case of kidney disease, dosage adjustment is important. For long-term allergic reactions, the course is 3-6 weeks. In case of short-term effects of allergens on the body, the medicine is used for no more than a week.
Cetirizine tablets are taken orally and should not be chewed. It is recommended to drink before bedtime. Children from 6 to 12 years old are prescribed 10 mg once a day if their weight is more than 30 kg and 5 mg per day if their body weight is up to 30 kg. For patients over 12 years of age, 10 mg per day is indicated.
Cetirizine
Data obtained from clinical studies
Review
The results of clinical studies have demonstrated that the use of cetirizine in recommended doses leads to the development of minor undesirable effects on the DNS, including drowsiness, fatigue, dizziness and headache. In some cases, paradoxical stimulation of the central nervous system has been reported.
Despite the fact that cetirizine is a selective blocker of peripheral H1 receptors and has virtually no anticholinergic effect, isolated cases of difficulty urinating, disturbances of accommodation and dry mouth have been reported.
Liver dysfunction has been reported, accompanied by increased levels of liver enzymes and bilirubin. In most cases, adverse events resolved after discontinuation of cetirizine dihydrochloride.
List of unwanted side reactions
Data from double-blind, controlled clinical trials comparing cetirizine with placebo or other antihistamines given at recommended doses (10 mg once daily for cetirizine) in more than 3200 patients are available on which to conduct a reliable analysis safety data.
According to the results of the pooled analysis, in placebo-controlled studies with the use of cetirizine at a dose of 10 mg, the following adverse reactions were identified with a frequency of 1.0% or higher:
Adverse reactions (WHO terminology) | Cetirizine 10 mg (n = 3260) | Placebo (n = 3061) |
General violations and violations in injection site Fatigue | 1,63% | 0,95% |
Nervous system disorders | 1,10% | 0,98% |
Dizziness | ||
Headache | 7,42% | 8,07% |
Gastrointestinal disorders Abdominal pain | 0,98% | 1,08% |
Dry mouth | 2,09% | 0,82% |
Nausea | 1,07% | 1,14% |
Mental disorders Drowsiness | 9,63% | 5,00% |
Respiratory, thoracic and mediastinal disorders Pharyngitis | 1,29% | 1,34% |
Although the incidence of somnolence in the cetirizine group was higher than that in the placebo group, most cases were mild or moderate in severity. When objectively assessed in other studies, it was confirmed that the use of cetirizine at the recommended daily dose in healthy young volunteers does not affect their daily activities.
Children
In placebo-controlled studies, the following adverse reactions were observed with an incidence of 1% or greater in children aged 6 months to 12 years:
Adverse reactions (WHO terminology) | Cetirizine (n = 1656) | Placebo (n =1294) |
Gastrointestinal disorders Diarrhea | 1,0% | 0,6% |
Mental disorders Drowsiness | 1,8% | 1,4% |
Respiratory, thoracic and mediastinal disorders Rhinitis | 1,4% | 1,1% |
General disorders and disorders at the injection site Fatigue | 1,0% | 0,3% |
Post-registration experience
In addition to the adverse events identified during clinical trials and described above, the following adverse reactions were observed during post-registration use of the drug.
Adverse events are presented below by MedDRA organ system class and incidence, based on data from post-marketing use of the drug.
The incidence of the adverse reactions listed below was determined according to the following (World Health Organization classification): very common (> 10%), common (> 1%, < 10%), uncommon (> 0.1%, < 1%) , rare (> 0.01%, < 0.1%), very rare (< 0.01%), frequency unknown (cannot be estimated using available data).
— Blood and lymphatic system disorders: very rare -
thrombocytopenia.
— Immune system disorders: rarely -
allergic reactions;
very rarely
- anaphylactic shock.
— Metabolic and nutritional disorders: frequency unknown
- increased appetite.
— Mental disorders: uncommon -
excitation;
rarely -
aggression, confusion, depression, hallucinations, sleep disturbance;
very rarely -
tic;
frequency unknown -
suicidal thoughts, sleep disturbances (including nightmares).
— Nervous system disorders: uncommon
- paresthesia;
rarely -
convulsions;
very rarely -
taste perversion, dyskinesia, dystonia, fainting, tremor;
frequency unknown -
memory impairment, including amnesia, deafness.
— Visual disturbances: very rarely -
disturbance of accommodation, blurred vision, nystagmus;
frequency unknown -
vasculitis.
— Hearing and labyrinthine disorders: frequency unknown -
vertigo.
-
Cardiac disorders : rarely -
tachycardia.
— Gastrointestinal disorders: uncommon -
diarrhea.
— Disorders of the liver and biliary tract: rarely -
liver failure with changes in liver function tests (increased activity of transaminases, alkaline phosphatase, gamma-glutamyltransferase and bilirubin).
— Skin and subcutaneous tissue disorders: uncommon
- rash, itching;
rarely -
urticaria;
very rarely -
angioedema, persistent drug erythema.
— Renal and urinary tract disorders: very rare -
dysuria, enuresis;
frequency unknown -
urinary retention.
— Musculoskeletal and connective tissue disorders: frequency unknown -
arthralgia.
— General disorders and administration site disorders: uncommon
- asthenia, malaise;
rarely -
peripheral edema.
Research: rare
- increase in body weight.
Description of selected adverse reactions
Cases of pruritus (including intense pruritus) and/or urticaria have been reported following discontinuation of cetirizine.
Adverse Reaction Alert
A system for reporting suspected adverse reactions after registration of a medicinal product is of great importance.
This allows continuous monitoring of the benefit/risk ratio of the drug.
How many days should you take Cetirizine?
The duration of antihistamine therapy directly depends on the diagnosis. On average, the medicine is prescribed for 1 week. The maximum duration is a month.
According to external factors and the patient’s well-being, course correction is possible.
Can I take it during pregnancy?
There have been no clinical trials on the use of the drug during pregnancy. Therefore, bearing a child is an absolute contraindication to the use of the drug.
Use during pregnancy
The instructions for the drug say that Cetirizine should not be taken while pregnant. This is due to the fact that no studies have been conducted on pregnant women. Animal studies have not shown any adverse reactions to the fetus. There is also no information on the effects of the drug during lactation, so you should avoid taking it during breastfeeding.
A few studies indicate that taking the drug in the 1st trimester has no effect on the number of congenital defects, the frequency of miscarriages and the premature birth of a baby. The weight of the newborn also did not differ from normal values.
If a pregnant woman experiences allergic reactions, then, taking into account the possible risks, it is better to give preference to Fencarol, cetirizine, which should be avoided in the first trimester.