Symptoms (when taking the drug in a dose of more than 5 tablets.): signs of intoxication in the form of drowsiness; in children - anxiety, increased irritability, the appearance of signs of anticholinergic action in the form of a delay in urine, dry mouth, constipation.
Treatment: taking the drug should be stopped, peeled, take activated carbon, immediately consult a doctor.
When studying the drug interaction of cetyrizin with pseudoephedrine, cimetidine, ketokonazole, redytromycin, azithromycin, diazepam, glypidine and antipyrin, clinically significant unwanted interactions were not detected.
With simultaneous use with theophylline (400 mg / day), the total clearance of cetyrizin is reduced by 16% (theophylline kinetics does not change).
With simultaneous use with AUC ritonavir, cetyrizin increased by 40%, while the same indicator of the ritonavir slightly changed (−11%).
With simultaneous use with macrolides (azitromycin, red bloodmicin) and ketoconazole, changes to the ECG were not noted.
When using the drug in therapeutic doses, data on the interaction with alcohol were not obtained (at a blood alcohol concentration of 0.5 g / l). Nevertheless, one should refrain from drinking alcohol during therapy with a drug in order to avoid oppression of the central nervous system.
A three-day “laundering” period is recommended before the appointment of allergological samples due to the fact that H1-histamines blockers inhibit the development of skin allergic reactions.
No medicinal interactions of cetyricin with other drugs were noted.
Based on the results of studies of the drug interaction of cetyrizin, in particular studies of the interaction with pseudoephedrine or theophyllin at a dose of 400 mg / day, there were no clinically significant interactions.
The simultaneous use of cetyrizin with alcohol and other drugs that depress the central nervous system can further reduce the concentration and speed of reactions, although cetrizin does not increase the effect of alcohol (at its concentration in the blood of 0.5 g / l).
It is not recommended to combine taking the drug Zinzet with other drugs without a doctor’s consultation. At the same time, taking with broncholithic drugs containing the theophylline as the active substance, an increase in the frequency of side effects of the drug Zincet. Data on the interaction of cetyricine with alcohol has not yet been received. Despite this, the use of alcoholic beverages in the treatment of Zincet is not recommended.
It is not recommended to combine the use of Cetizine with other drugs without a doctor’s consultation. At the same time, with broncholithic drugs containing the theophylline as the active substance, an increase in the frequency of side effects of the Cetizine drug. Data on the interaction of cetyricine with alcohol has not yet been received. Despite this, the use of alcoholic beverages in the treatment of Cetizine is not recommended.
Usually the drug is well tolerated. In some cases, headache, drowsiness, dizziness, excitation, dry mouth are possible; disorders from the gastrointestinal tract: dyspepsia, abdominal pain, meteorism. As an exception, signs of hypersensitivity to the drug (short, swelling, shortness of breath) are possible. In this case, treatment with the drug should be stopped immediately and an urgent appeal to the doctor. It is necessary to inform the doctor about all side (unusual) effects.
Cetirizin is an active substance of the drug Cetizine® - is a metabolite of hydroxysine, belongs to the group of competitive antagonists of histamine and blocks H1histamine receptors.
Cetirisin warns development and facilitates the course of allergic reactions, and has antitudent and anti-exudative effect. Cetirisin affects the early histone-dependent stage of allergic reactions, limits the release of inflammation mediators at a late stage of an allergic reaction, and also reduces the migration of eosinophiles, neutrophils and basophiles, stabilizes the membranes of fat cells. Reduces the permeability of capillaries, prevents the development of tissue edema, relieves the spasm of smooth muscles. Eliminates the skin reaction to the introduction of histamine, specific allergens, as well as cooling (with cold urticaria). Reduces histin-induced bronchocongricia with bronchial asthma of the light current.
Cetirisin does not have an anti-cholinergic and anti-serotonin effect. In therapeutic doses, the drug has virtually no sedative effect. After taking cetyrizin in a single dose of 10 mg, its action develops after 20 minutes (in 50% of patients), after 60 minutes (in 95% of patients) and lasts more than 24 hours. Against the background of course treatment, tolerance for the antihistamine action of cetyrizin does not develop. After the cancellation of therapy, the effect persists up to 3 days.
Cetirisin is a metabolite of hydroxisin, belongs to the group of competitive antagonists of histamine and blocks N1- histamine receptors.
In addition to the antihistamine effect, cetyrizin prevents development and facilitates the course of allergic reactions: at a dose of 10 mg 1 or 2 times a day inhibits the late phase of the aggregation of eosinophiles in the skin and conjunctiva of patients exposed to atopia.
Clinical efficiency and safety. Studies in healthy volunteers have shown that cetirisin in doses of 5 or 10 mg significantly inhibits the reaction in the form of rash and redness to inject histamine into the skin at a high concentration, but a correlation with efficiency has not been established. A 6-week placebo-controlled study involving 186 patients with allergic rhinitis and concomitant bronchial asthma of mild to moderate currents shows that taking cetrizin at a dose of 10 mg 1 time per day reduces the symptoms of rhinitis and does not affect the function of the lungs.
The results of this study confirm the safety of the use of cetyrin in patients suffering from allergies and bronchial asthma of the mild and medium-lived course.
A placebo-controlled study showed that taking cetrizin at a dose of 60 mg / day for 7 days did not cause a clinically significant extension of the QT interval. Taking cetyrin in the recommended dose showed an improvement in the quality of life of patients with year-round and seasonal allergic rhinitis.
Children. In a 35-day study involving patients aged 5–12 years, there were no signs of immunity to the antihistamine effect of cetyrizin. The normal reaction of the skin to the histamine was restored within 3 days after the abolition of the drug when it was repeatedly used.
A 7-day placebo-controlled study of cetyricine in the form of syrups involving 42 patients aged 6 to 11 months demonstrated the safety of the drug.
Cetirizin was assigned at a dose of 0.25 mg / kg 2 times a day, which approximately corresponded to 4.5 mg per day (dose range ranged from 3.4 to 6.2 mg per day).
The use of children from 6 to 12 months is possible only by appointment of a doctor and under strict medical supervision.
The pharmaceutical parameters of cetyrizin change linearly.
Suction. After taking it inside, the drug is quickly and completely absorbed from the LCD. Eating does not affect the completeness of absorption, although its speed decreases. In adults, after a single medication in therapeutic dose Cmax in blood plasma is 300 ng / ml and is achieved through (1 ± 0.5) h.
Distribution. Cetirisin on (93 ± 0.3)% binds to blood plasma proteins. Vd is 0.5 l / kg. When taking the drug at a dose of 10 mg for 10 days, cetyrizin cumulation is not observed.
Metabolism. In small quantities, it is metabolized in the body by O-dealkylation (unlike other antagonists H1-histamines that are metabolized in the liver using a cytochrome system) with the formation of pharmacologically inactive metabolite.
The conclusion. In adults T1/2 is approximately 10 hours; in children from 6 to 12 years old - 6 hours, from 2 to 6 years old - 5 hours, from 6 months to 2 years old - 3.1 hours. Approximately 2/3 of the accepted dose of the drug is withdrawn by the kidneys unchanged.
In elderly patients and patients with chronic liver diseases with a single medication at a dose of 10 mg T1/2 increases by about 50%, and system clearance is reduced by 40%.
In patients with renal failure of mild severity (Cl creatinine> 40 ml / min), pharmacokinetic parameters are similar to those in patients with normal kidney function.
In patients with moderate renal failure and in patients undergoing hemodialysis (Cl creatinine <7 ml / min), when taking the drug inward at a dose of 10 mg T1/2 lengthens 3 times, and the total clearance is reduced by 70% relative to these indicators in patients with normal kidney function, which requires a corresponding change in the dosing mode.
Cetirisin is practically not removed from the body during hemodialysis.
The pharmaceutical parameters of cetyrizin when used in doses of 5 to 60 mg change linearly.
Suction. Cmax in blood plasma is achieved through (1 ± 0.5) h and is 300 ng / ml.
Various pharmacokinetic parameters, such as Cmax in blood plasma and AUC are homogeneous.
Eating does not affect the completeness of cetyrizin absorption, although its speed decreases. The bioavailability of various dosage forms of cetyrizin (rathering, capsules, tablets) is comparable.
Distribution. Cetirisin on (93 ± 0.3)% binds to blood plasma proteins.
Vd is 0.5 l / kg. Cetirisin does not affect the binding of warfarin with proteins.
Metabolism. Cetirisin is not exposed to extensive primary metabolism.
The conclusion. T1/2 is approximately 10 hours.
When taking the drug in a daily dose of 10 mg for 10 days, cetyrizin cumulation was not observed.
Approximately 2/3 of the accepted dose of the drug is withdrawn with urine in an unchanged form.
Elderly patients. In 16 elderly patients with a single medication in a dose of 10 mg T1/2 was 50% higher, and clearance was 40% lower compared to patients of not old age. The decrease in cetirizin clearance in older patients is probably due to a decrease in the function of the kidneys in this category of patients.
Renal failure. In patients with renal failure of mild severity (Cl creatinine> 40 ml / min), pharmacokinetic parameters are similar to those in healthy volunteers with normal kidney function.
In patients with moderate renal failure and in patients undergoing hemodialysis (Cl creatinine <7 ml / min), when taking the drug inward at a dose of 10 mg T1/2 lengthens 3 times, and the overall clearance is reduced by 70% relative to healthy volunteers with normal kidney function.
For patients with renal failure of moderate or severe degree, a corresponding change in the metering mode is required (see. “Method of application and doses”).
Cetirisin is poorly removed from the body during hemodialysis.
Pediatric failure. In patients with chronic liver diseases (hepatocellular, cholestatic and biliar cirrhosis) with a single medication at a dose of 10 or 20 mg T1/2 increases by about 50%, and clearance is reduced by 40% compared to healthy entities. Correction of the dose is necessary only if the patient with liver failure also has concomitant renal failure.
Children. T1/2 in children from 6 to 12 years old it is 6 hours, from 2 to 6 years old - 5 hours, from 6 months to 2 years old - reduced to 3.1 hours.
