Velaxin tablets user manual
Velaxin belongs to the group of antidepressants.
Form of issue and composition
Velaxin is released in tablets, in dosages of 37.5 mg and 75 mg, 14 tablets per package. Tablets in blister (7 pieces) with the instruction are placed in a cardboard package.
The main active ingredient is venlafaxine hydrochloride.
Auxiliary components: lactose monohydrate, microcrystalline cellulose, sodium starch glycolate, colloidal silicon dioxide anhydrous, magnesium stearate.
Pharmacodynamics. Venlafaxine is an antidepressant. By chemical structure differs from other groups of this class of drugs (tetracyclic, tricyclic, etc.). The therapeutic effect of venlafaxine is due to its ability to potentiate the transmission of nerve impulses to the central nervous system. The active substance and its active metabolite exert a strong inhibitory effect on the reuptake of serotonin and norepinephrine, and a weak inhibitory effect on the reuptake of dopamine. Also, venlafaxine and its metabolite reduce the activity of β-adrenergic receptors both after a single application, and with regular long-term admission.
Venlafaxine does not have an affinity for M-cholinergic receptors, H-cholinergic receptors, H-1 histamine-receptors, and α-1 adrenergic receptors of the brain. Does not suppress MAO activity. Does not affect the phencyclidine, opioid, benzodiazepine receptors.
Pharmacokinetics. Venlafaxine is well absorbed from the digestive tract. The maximum concentration of the active substance in the blood is observed 2.4 hours after the drug administration, the maximum concentration of the active metabolite is 4.3 hours. If the drug is taken with food, the maximum concentration of the substance in the blood plasma is reached by 20-30 minutes faster. The maximum concentration and bioavailability do not change.
Venlafaxine is metabolized in the liver. With blood plasma proteins, 27% of venlafaxine and 30% of the active metabolite are bound. Their half-lives are, respectively, 5 and 11 hours. Active components and inactive metabolites are excreted by the kidneys.
Indications for use
Velaxin is prescribed for treatment and prevention of depressions of various nature.
Velaxin is contraindicated:
- with severe functional disorders of the liver;
- with severe functional disorders of the kidneys;
- with simultaneous treatment with MAO inhibitors;
- at the age of 18 years (the efficacy and safety of Velaxin application for this age group of patients is not proven);
- during pregnancy and breastfeeding;
- with individual intolerance or hypersensitivity to the main or one of the auxiliary components of the drug.
Dosing and Administration
Velaxin tablets are taken whole inside, during the meal. The initial recommended daily dose of the drug is 75 mg (37.5 mg in two divided doses). If after 2-3 weeks of treatment a pronounced therapeutic effect is not observed, the daily dose is increased to 150 mg per day (75 mg twice).
In severe depressive disorders and conditions requiring treatment in the hospital, the initial daily dose of the drug is 150 mg (75 mg in two divided doses), after which every 2-3 days the dose is increased by 75 mg to achieve the desired therapeutic effect. The maximum permissible daily dosage of Velaxin is 375 mg. The daily dose of the drug can gradually decrease after reaching the expected therapeutic effect.
For maintenance treatment and prevention of recurrence of the disease, Velaxin is prescribed in the minimum effective therapeutic dosages used in the treatment of a depressive episode. The duration of maintenance therapy can be 6 months or more.
During treatment with Velaxin, unwanted side effects from various body systems may develop:
- from the nervous system - dizziness, the appearance of unusual dreams, insomnia and nervous excitement, stupor, paresthesia, increased muscle tone and tremor, yawning; infrequent apathy and hallucinations develop; rarely epileptic seizures and manic reactions are noted;
- from the sense organs - visual impairment, disruption of accommodation (the ability to clearly distinguish objects at different distances), mydriasis (dilated pupil), a violation of taste perception;
- from the side of the cardiovascular system - hyperemia of the skin, tachycardia , postural hypotension, arterial hypertension;
- on the part of the hematopoietic system - ecchymosis (hemorrhages in the skin and mucous membranes), thrombocytopenia, lengthening the duration of bleeding;
- on the part of the digestive system and the liver - dry mouth, loss of appetite, nausea and vomiting, constipation, rarely - hepatitis;
- from the side of metabolism - increased serum cholesterol concentration, weight loss, functional liver tests, hyponatremia, insufficient secretion of ADH;
- on the part of the excretory system - dysuria (more often at the beginning of the act of urination), urinary retention;
- on the part of the reproductive system - erectile dysfunction, anorgasmia, decreased libido, menorrhagia;
- from other organs and systems - fatigue, weakness;
- dermatological reactions - increased sweating, photosensitivity;
- allergic reactions - skin rash, erythema multiforme, anaphylactoid reactions.
With prolonged therapy, the incidence and severity of side effects decreases and, as a rule, no withdrawal of the drug is required.
With a decrease in daily dose or after Velaxin cancellation, dizziness and headache, increased fatigue and drowsiness, dry mouth, nausea and vomiting, diarrhea, anorexia, insomnia, anxiety and anxiety, nervous irritability, disorientation, paresthesia, sweating may occur. Such phenomena are usually poorly expressed and do not require special treatment, they pass by themselves. To prevent the development of withdrawal syndrome at the end of treatment, a slow, gradual dose reduction of Velaxin is recommended.
When an overdose of Velaxin is noted: a change in the parameters of the electrocardiogram, ventricular or sinus tachycardia, hypotension, bradycardia, a change in consciousness (lowering the level of wakefulness), convulsive conditions. When doses of Velaxin are exceeded in combination with taking alcoholic beverages and / or using other psychotropic medicines, a lethal outcome is possible.
Treatment of poisoning with Velaxin is symptomatic. At the same time, continuous monitoring of vital functions (circulation, heart, respiration) is carried out. Sorbents are used to reduce the absorption of matter. There is a threat of aspiration, so induce vomiting is not recommended. The active substance and its metabolites are not withdrawn during dialysis. There are no specific antidotes to venlafaxine.
During the appointment and use of Velaxin, it is important to consider the following points:
- with depressive disorders it is important to consider the possibility of a suicide attempt, therefore, in order to reduce the risk of overdose, the drug is prescribed in minimal effective dosages, and the patient is under constant medical supervision;
- in patients with affective disorders, hypomanic or manic conditions may develop, so patients with manic conditions should be under constant medical supervision during treatment;
- when epileptic seizure develops during treatment with Velaxin, treatment should be interrupted;
- in some patients, when taking Velaxin, a dose-dependent increase in blood pressure is noted, therefore, a constant control of blood pressure is required, especially with increasing doses;
- the drug is used cautiously in patients with tachyarrhythmia, since it can cause an increase in the heart rate (when taking high doses - especially);
- in elderly patients, dizziness and imbalance are possible;
- it is necessary to take into account the content of lactose in tablets when administered to patients with lactose intolerance;
- during the treatment you can not drink alcohol;
- in patients with cirrhosis of the liver, the concentration of the active substance and metabolites in the blood increases, the rate of their excretion decreases;
- with mild hepatic insufficiency, the doses are not corrected;
- with moderate hepatic insufficiency, the recommended dosage of the drug is reduced by 50%;
- with severe hepatic insufficiency, Velaxin should not be prescribed (reliable data on the safety of treatment of such patients with Velaxin are not available);
- with mild renal failure, there is no need for correction of the doses of the drug;
- with moderate renal failure, the half-life of the active substance is reduced, so the dosage of the drug for such patients should be reduced by 25-50% (with the prescribed daily dose taken once);
- with severe renal failure, Velaxin is not recommended (reliable data on the safety of the drug for severe kidney disorders are absent);
- the drug is not prescribed during hemodialysis;
- Velaxin can be administered after the end of the hemodialysis session at a dosage of 50% less than the usual recommended daily dose;
- with caution the drug is prescribed for elderly patients because of the high probability of disrupting the kidneys (it is recommended to use the lowest effective therapeutic dose, and if necessary, the patient should be under constant monitoring by the doctors);
- At the end of the treatment course, the dosage of Velaxin is reduced gradually, which makes it possible to eliminate the risks caused by drug withdrawal (the time of reduction of the drug doses is determined individually, taking into account the dosing regimen used, the duration of treatment and the patient's response to reduced doses);
- with simultaneous conduct of electroconvulsive therapy, caution is required (clinical experience with Velaxin is not available under such conditions);
- the drug affects the nervous system, so during the treatment it is impossible to drive vehicles and other mechanisms.
Velaxin is administered with caution in the following diseases and conditions:
- recently suffered myocardial infarction;
- unstable angina ;
- arterial hypertension;
- convulsions ;
- angle-closure glaucoma;
- increased intraocular pressure;
- manic states;
- epileptic seizures in the anamnesis;
- increased tendency to bleeding and hemorrhage from the skin and mucous membranes;
- low body weight.
- the simultaneous administration of Velaxin with MAO inhibitors is contraindicated;
- the time interval between the onset of admission of Velaxin and the end of treatment with MAO inhibitors should be at least 14 days (the exception is the administration of the reversible MAO inhibitor of moclobemide - in this case, the interruption between the administration of funds may be 24 hours);
- MAO inhibitors can be taken at least 7 days after the end of the reception of Velaxin;
- with the simultaneous use of Velaxin and haloperidol, the concentration of haloperidol in the blood and its therapeutic effect increase;
- in combination with diazepam, the pharmacokinetics of both drugs does not change;
- in combination with clozapine, its concentration in the blood increases, and the side effects (eg epileptic seizures) are increased;
- with simultaneous administration with risperidone, the pharmacokinetics of both drugs does not change;
- in combination with alcohol, psychomotor reactions are enhanced;
- in combination with cimetidine metabolism of Velaxin is slightly reduced (more pronounced in elderly people and patients with hepatic impairment);
- when applied simultaneously with warfarin, the anticoagulant effect of the latter increases;
- Velaxin does not interact with hypoglycemic agents and antihypertensive drugs (ACE inhibitors, beta-adrenoblockers, diuretics);
- in combination with indinavir, Velaxin reduces its maximum concentration in the blood.
Pregnancy and lactemia
There is no reliable data on the safety of Velaxin for pregnant women. Therefore, the drug is prescribed during pregnancy only in those situations where the expected benefit for the mother exceeds the potential risks to the fetus.
If the drug was taken by a pregnant woman shortly before the birth, the newborn can develop withdrawal syndrome.
Venlafaxine and its metabolites are excreted in breast milk, so if necessary, breastfeeding should be discontinued (there is no data on the safety of the drug for infants).
The structural analogues of Velaxin containing the same active substance include preparations: Epevelon, Venlaksor, Velafax, Efektin.
Terms and conditions of storage
Velaxin is stored in a place protected from moisture and sunlight, inaccessible to children. Shelf life is 5 years. Do not use the tablet after the expiry date indicated on the package.
Velaxin tablets 75mg - 850-1050 rub.
Velaxin tablets 37.5 mg - 670-850 rub.