When administered, the effective dose for adults is 15-45 mg / day, mainly 1 time / day before bedtime. Cheap mirtazapine The dose is gradually increased to 30-45 mg / day. The antidepressant effect develops gradually, usually after 2-3 weeks from the start of treatment, however, administration should be continued for another 4-6 months. If no therapeutic effect is observed within 6-8 weeks of treatment, treatment should be discontinued.
Mirtazapine withdrawal is carried out gradually.
Pharmacodynamics and pharmacokinetics
The main component of the drug is the active central presynaptic α2 receptor antagonist, which can increase the noradrenergic and serotonergic transmission to the nervous system.
Serotonergic transmission is enhanced through 5-HT1 receptors, since mirtazapine can block 5-HT2 and 5-HT3 receptors. Also, the drug is able to block H1 receptors, which determines its sedative effect..
Therapeutic doses of Mirtazapine are not characterized by anticholinergic activity or a negative effect on the cardiovascular system.
After oral administration, the drug is rapidly and fully absorbed, with 50% bioavailability. The maximum concentration in the blood plasma is reached within 2 hours.
About 85% of mirtazapine is bound to plasma proteins. Achieving a stable concentration is observed after 3-4 days, then the accumulation passes.
Pharmacokinetic parameters of the drug have a linear dependence on the dose taken. Eating does not affect the pharmacokinetics of the active substance.
Mirtazapine is characterized by an active metabolism with the formation of several metabolites. Excretion of the drug from the body occurs with urine and feces.
Mirtazapine is contraindicated in case of individual intolerance to the substances included in the tablets, as well as during the treatment of children under the age of 18.
The timely adjustment of the dose and constant medical supervision requires the use of medication in the treatment of patients in whom:
- low blood pressure;
- cerebrovascular disorders;
- impaired functioning of the cardiovascular system in the form of angina pectoris or heart attacks;
- mania, drug dependence;
- epilepsy and organic brain damage (tablets can contribute to the occurrence of convulsive conditions).
Particular care is required when taking tablets with patients with diabetes mellitus, glaucoma (in a closed-angle form), difficulty urinating.
The safety of the use of Mirtazapine tablets during treatment of pregnant and lactating patients has not been established.