Description of the active substance:
This information is a reference and it is not enough that the drug has been prescribed by a doctor ..
PHARMACHOLOGIC EFFECT
An antiviral agent. A non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1).
PHARMACOKINETICS
It is subjected to intensive metabolism in the liver with the participation of enzymes of the CYP system. Based on in vitro studies, it is considered that CYP3A4 and CYP2B6 are the main isoenzymes responsible for the metabolism of efavirenz. According to a number of studies, depending on the dose, efavirenz is an inhibitor or inducer of CYP3A4.
Less than 1% is excreted in the urine unchanged.
INDICATIONS
Infections caused by HIV-1 (as part of combination therapy).
DOSING MODE
Used in combination therapy with other antiretroviral drugs (protease inhibitors and / or nucleosides - reverse transcriptase inhibitors).
When ingested for adults and children weighing more than 40 kg, the recommended dose is 600 mg / day.
For children and adolescents (3 to 17 years), depending on the age of the dose is 200-400 mg / day. The recommended dose for children weighing more than 40 kg is 600 mg / day.
The frequency of reception - 1 time / day, regardless of food intake.
SIDE EFFECT
Dermatological reactions: often (especially in children) - maculopapular rash; in isolated cases - a severe rash, accompanied by blisters, wetting peeling and ulcers.
From the digestive system: often - nausea; possible diarrhea.
From the side of the central nervous system: possible dizziness, headache, insomnia, fatigue, reduced concentration of attention.
Allergic reactions: in isolated cases - erythema multiforme, Stevens-Johnson syndrome.
On the part of laboratory indicators: increased activity of ALT, AST, GGT, amylases, increase in the level of total bilirubin, increase in the concentration of glucose in the blood.
CONTRAINDICATIONS
Simultaneous application with terfenadine, astemizole, cisapride, midazolam or trizolam; increased sensitivity to efavirenz.
PREGNANCY AND LACTATION
Adequate and strictly controlled clinical studies of safety of use in pregnancy have not been conducted. The application is only possible in cases where the intended benefit to the mother exceeds the potential risk to the fetus.
During the treatment period, women of childbearing age should use reliable methods of contraception. Since the possible interaction of efavirenz with oral contraceptives is not fully understood, reliable barrier barrier methods should be used in addition to oral contraceptives.
It is not known whether efavirenz is excreted in human milk.
In experimental studies , it has been established that efavirenz has a teratogenic and embryotoxic effect. It is shown that efavirenz is excreted in breast milk in lactating rats.
APPLICATION FOR VIOLATIONS OF THE FUNCTION OF KIDNEYS
Clinical experience with efavirenz in patients with chronic liver disease is limited. Use with caution in patients with severe impaired liver function (because efavirenz is subjected to intensive metabolism in the liver with the participation of enzymes of the CYP system).
During the period of treatment it is recommended to constantly monitor the activity of hepatic transaminases in patients with hepatitis B or C or suspected of these infections in the anamnesis and in patients receiving other drugs that can have hepatotoxic effect. In the case of an acute persistent increase in transaminase activity to a level more than 5 times that of UHN, the benefits of continuing treatment with the risk of a significant hepatotoxic effect should be compared.
APPLICATION FOR CHILDREN
In children under 3 years of age or body weight less than 13 kg, the safety and efficacy of efavirenz have not been studied.
SPECIAL INSTRUCTIONS
When choosing new antiretroviral drugs for combination therapy, the possibility of cross-resistance of the virus should be considered.
With the withdrawal of efavirenz should also consider the possibility of canceling treatment with other antiretroviral drugs to avoid the emergence of resistant viruses.
Clinical experience with efavirenz in patients with chronic liver disease is limited. Use with caution in patients with severe impaired liver function (because efavirenz is subjected to intensive metabolism in the liver with the participation of enzymes of the CYP system).
During the period of treatment it is recommended to constantly monitor the activity of hepatic transaminases in patients with hepatitis B or C or suspected of these infections in the anamnesis and in patients receiving other drugs that can have hepatotoxic effect. In the case of an acute persistent increase in transaminase activity to a level more than 5 times that of UHN, the benefits of continuing treatment with the risk of a significant hepatotoxic effect should be compared.
During the treatment period, the level of cholesterol should be constantly monitored.
In children under 3 years of age or body weight less than 13 kg, the safety and efficacy of efavirenz have not been studied.
DRUG INTERACTION
With simultaneous use of efavirenz with terfenadine, astemizole, cisapride, midazolam or trizolam, competitive drug interaction for the isoenzyme CYP3A4 is observed, which can lead to inhibition of the metabolism of these drugs and create the possibility of serious and / or life-threatening consequences - severe arrhythmias, prolonged sedation or oppression respiration).
Under the influence of efavirenz it is possible to reduce the concentration in the plasma of preparations that are substrates of the isoenzyme CYP3A4.
