Description overdue on 28.01.2012

Antirheumatic drugs.   Arava has marked immunosuppressive activity, also has anti-inflammatory and anti-proliferative effect. Active ingredient - leflunomide . The mechanism of action of leflunomide is associated with inhibition of the enzyme degidroorotatdegidrogenazy. The studies have shown that the active metabolite of leflunomide that forms in metabolism in the body, selectively interacts with this enzyme, which is accompanied by inhibition of the proliferation of T-lymphocytes. This mechanism of action provides immunosuppressive effect . T-lymphocytes trigger a chain of reactions that underlie the pathogenesis rheumatoid arthritis And because depression cellular immunity   positive effect on the course of the disease in its acute stage .  This is not the only effect of leflunomide .  In addition to inhibition of T cell proliferation Arava reduces susceptibility to tissue receptors Interleukin-2 .  The last factor is the trigger for the start of the inflammatory response in tissues and organs, so that the decrease in sensitivity to the mediator has anti-inflammatory effect .  Arava take into orally without food (the latter does not affect bioavailability) .  In the intestine, it absorbed 90% of active ingredient leflunomide .  Leflunomide is rapidly metabolized in the liver to produce the active form, which affects the cellular part of the immune response .  Half-life time - up to two weeks .  The effect of receiving leflunomide occurs within four - six weeks after starting the drug tends to be cumulated in organs and tissues, and therefore the action is maintained for a long period of time - up to six months .

Indications:

Arava (leflunomide) is used to treat patients with rheumatoid arthritis in the active phase. There is also evidence of the possibility of the use of the drug in psoriatic arthritis (also in the active form).

Contraindications:

Arava is contraindicated in the presence of hypersensitivity to the active substance. It should appoint leflunomide in violation of the liver, severe immune deficiency (including AIDS). Contra-indications Arava will also be significant violations of hematopoiesis, expressed anemia , Thrombocytopenia or leukopenia . Arava should not be prescribed for severe infectious diseases. Renal failure   both moderate and severe, it is a relative contraindication to leflunomide (due to lack of experience in the application). Decreasing the amount of protein in the blood may be a contraindication for the purpose of leflunomide. Arava is not intended to and during pregnancy. You can not assign leflunomide while breast-feeding.

Side effect:

Cardiovascular system : While taking leflunomide may increase blood pressure, in very rare cases may be connected inflammation of blood vessels ( vasculitis ). Digestive tract   may react to the drug with diarrhea, vomiting or nausea, loss of appetite. Often there is a violation of the liver, which can be fixed to improve the activity of specific enzymes transaminases . It is also possible to increase the level of bilirubin in the blood plasma. Much less often while taking leflunomide develops hepatitis, which may be accompanied by hepatic insufficiency . In the worst case can occur in the liver rhabdomyolysis.   He suffers when receiving Arabia musculoskeletal system In particular, ligaments (the most common complication - an inflammation of the tendons, tendovaginitis ). As leflunomide has an impact on all actively proliferating tissues, with its reception may occur hair loss and change in the state of the skin (dry skin, eczema symptoms) may develop polymorphic exudative erythema   and Lyell's syndrome. Also an allergic reaction to medication may appear in the form of anaphylactic shock. Hematopoietic system   can react to receiving leflunomide leukopenia, a decrease in the level of red blood cells, low thrombocytopenia. In more severe cases may develop agranulocytosis . Leflunomide in combination with other immunosuppressive agents increases the risk of infections, malignancies, diseases of the hematopoietic system.

Mode of application:

Arava available in tablets that contain 10 mg, 20 mg or 100 mg of leflunomide. The drug is only possible with the direct participation of a doctor who has experience in the use of such drugs in the treatment of rheumatoid arthritis. Typically, therapy is started with a shock starting dose of 100 mg per day, which is administered for three days. Then move on to maintenance dosage of 10 or 20 mg per day. Take once regardless of the meal, washed down with a drug with plenty of water.

Special instructions:

As leflunomide has a property to accumulate in tissues and organs, and, among other things, it has a long half-life, after stopping Arava you need to perform the procedure of "laundering". For this purpose, the patient is prescribed kolestiramin at a dose of 8 g three times a day for 11 days, or you can use as an alternative means Activated carbon   It must take the following scheme: 50 g of pulverized powder four times a day for the same eleven days .  As may develop serious complications from the liver, receiving leflunomide should be accompanied by constant supervision of liver enzymes, and other indicators of liver parenchyma .  Men who receive leflunomide should be aware of its possible toxic effect on the sperm, and therefore there is the need for a proven means of contraception .  Children under 18 years Arava drug is not prescribed .  Women of childbearing age before the start of therapy with leflunomide must be tested for pregnancy gynecologist and warned of the possible consequences .  If a woman expresses a desire to have a child at the end of the course receive leflunomide, it must go through the procedure of washing, after which will be determined by the level of drug in the blood plasma .  After he drops to the level of 0, 02 mg per liter is necessary to wait for another month and a half, and only then we can think of conception .  Ideally, after treatment with leflunomide from conception to abstain for a further two years .  When receiving leflunomide possible overdose .  Treatment involves taking the same drugs that are used to launder - activated charcoal and cholestyramine .  Kolestiramin taken orally for 8 g 3 times during the day .  Activated carbon - or oral gavage 50 grams for six hours every day .

Drug Interactions:

Since leflunomide exerts a toxic effect on the liver, this effect may be increased when applying other hepatotoxic (including alcoholic beverages) and immunosuppressive agents. The same gain toxic effect   It may occur if intake of these medicines start without the above procedure "laundering". In rheumatoid arthritis, no cases of the interaction between leflunomide and cytostatic drug Methotrexate Which is also included in the treatment regimen of the disease. Leflunomide should be carefully used with drugs such as phenytoin, tolbutamide, warfarin, as leflunomide inhibits the enzyme responsible for the metabolism of these drugs. Leflunomide does not reduce the effectiveness of oral contraceptives .