Allohexal

Allohexal is a medicine that inhibits the production of uric acid.

The substance allopurinol is a structural analogue of the hypoxanthine component. It interferes with the binding of uric acid and has urostatic activity, which acts mainly due to the fact that allopurinol is able to inhibit the enzyme xanthine oxidase. As a result, the oxidation of hypoxanthine is catalyzed with the formation of xanthine, from which uric acid is formed. This allows uric acid values to be lowered and helps dissolve urates. [1]

Indications Allohexal

In pediatrics, it is used for such violations:

• nephropathy of the urate type, which developed during the treatment of leukemia;
• hyperuricemia of the secondary form, which has a different nature;
• congenital enzyme deficiency - for example, Lesch-Nyhan syndrome or congenital deficiency of the APRT component.

In adults, it is used in such cases:

• hyperuricemia (serum uric acid values - 500+ μmol), which cannot be controlled with diet;
• psoriasis;
• diseases associated with an increase in blood levels of uric acid (especially in the case of nephropathy or uric acid urolithiasis, as well as gout);
• secondary type hyperuricemia of a different nature;
• hyperuricemia of the secondary or primary type, which occurs against the background of various hemoblastoses (myeloid leukemia of a chronic nature, leukemia in the active phase and lymphosarcoma);
• radiation or cytostatic procedures for the treatment of neoplasms;
• the use of GCS in large volumes.

Release form

The release of the drug substance is made in the form of tablets - 10 pieces inside the cell pack; in a box - 5 such packs.

Pharmacokinetics

When administered orally, allopurinol is fully and at high speed absorbed into the blood. Gastric absorption is almost not observed. Suitable conditions for absorption are observed in the upper region of the small intestine and duodenum. After taking a standard therapeutic dose of 0.3 g, the plasma Cmax of allopurinol is recorded approximately after 1 hour and is equal to 1-2.6 μg / ml (average value is 1.8 μg / ml).

Metabolic transformations make it possible to obtain the metabolic element oxypurinol, which has a therapeutic effect. It reaches its Cmax values after 3-4 hours (they are 5-11 μg / ml (the average is 8.4 μg / ml)). The rate of formation is determined by the speed and intensity of the pre-systemic metabolic processes of a person.

Allopurinol, together with oxypurinol, almost do not participate in the synthesis with blood protein.

The term plasma half-life of allopurinol is approximately 40 minutes, and oxypurinol is within 17-21 hours. In almost one third of patients, the expected half-life of oxypurinol is 9-16 hours.

80% of the above components are excreted through the kidneys, and another 20% - by the intestines. In individuals with impaired renal function, the half-life of oxypurinol is increased.

Dosing and administration

For the age of 3-6 years, the medication is used in a portion of 5 mg / kg. For persons 6-10 years of age - 10 mg / kg. You need to take the medicine 3 times a day.

For an adult, the daily dosage is selected personally, taking into account the serum indicators of uric acid; often it equals 0.1-0.3 g of drugs per day. If necessary, the serving can be gradually increased by 0.1 g at 1-3 week intervals until the maximum result is obtained.

The size of the maintenance portion is 0.2-0.6 g per day; sometimes it can be increased to 0.6-0.8 g. With daily dosages above 0.3 g, it is required to divide them into 2-4 equal portions for consumption. In the case of an increase in dosage, it is necessary to monitor the serum levels of oxypurinol (they should not be higher than 15 μg / ml).

Persons with impaired renal function.

It is necessary to start therapy with a daily dosage of 0.1 g; it is allowed to increase it only in cases where the effect obtained from the medication is too weak. Dosage selection schemes:

• CC level above 20 ml per minute - 0.1-0.3 g of drugs per day;
• indicator in the range of 10-20 ml per minute - 0.1-0.2 g of allopurinol per day;
• values below 10 ml per minute - 0.1 g of the substance or higher portions, but with the intake after longer breaks (for example, 1-2 + days - taking into account the patient's condition and kidney function).

In people on hemodialysis, 0.3 g of Allohexal is administered at each of the sessions (2-3 times a week).

To prevent the development of hyperuricemia during chemotherapy and radiation therapy of neoplasms, an average of 0.4 g is used per day. It is necessary to start taking it 2-3 days before the start or simultaneously with the antiblastoma treatment; the use of drugs should be continued for several days after the completion of specific therapy.

The tablets should be taken without chewing, with a large amount of liquid after a meal.

The duration of the treatment cycle is determined by the course of the underlying pathology.

• Application for children

The medication is not used in persons under the age of 3 years.

Use Allohexal during pregnancy

It is forbidden to prescribe Allohexal during pregnancy or hepatitis B.

Contraindications

The main contraindications:

• strong sensitivity to allopurinol or other elements of the medication;
• severe hepatic / renal dysfunction.

Side effects Allohexal

At the initial stage of therapy, the development of a reactive gouty attack is possible.

Sometimes there are problems with the functioning of the gastrointestinal tract (vomiting, diarrhea and nausea) or epidermal disorders (urticaria, erythema, or itching).

Occasionally, fatigue, paresis, visual disturbances, weakness, depression and neuropathy occur. In addition, ataxia, cataracts, convulsions, dizziness, paresthesias, headaches, taste disorders and drowsiness are noted.

In people with renal insufficiency (when the dosage of drugs is not reduced), vasculitis with epidermal changes, as well as involvement of the liver and kidneys, may occur. If a patient has vasculitis, therapy should be discontinued immediately.

Among other side signs:

• symptoms of intolerance - epidermal manifestations, fever, arthralgia and chills;
• changes in blood counts (leukocytosis or leukopenia, as well as eosinophilia) and severe bone marrow damage (agranulocytosis, thrombocytopenia, or aplastic anemia), especially in people with kidney failure;
• epidermal lesions - TEH or MEE;
• hepatic dysfunction (a curable increase in transaminase and alkaline phosphatase levels in the blood), stomatitis and hepatitis;
• alopecia;
• peripheral neuritis or myalgia;
• drug-related tubulointerstitial nephritis associated with lymphocytic infiltration;
• hematuria or uremia;
• cholangitis in the active phase;
• xanthogenic stones;
• gynecomastia or erectile dysfunction;
• an increase in blood pressure values, diabetes mellitus or bradycardia.

Overdose

Signs of poisoning: vomiting, dizziness, diarrhea, oliguria and nausea.

Peritoneal and hemodialysis procedures are performed, as well as forced diuresis.

Interactions with other drugs

The therapeutic effect of allopurinol is weakened when used with substances that have a uricosuric effect (probenecid, sulfinpyrazone and benzbromarone), as well as with large portions of salicylates.

Allopurinol is able to potentiate the effects of many medications. For example, due to the fact that allopurinol can slow down the action of xanthine oxidase, the metabolic processes of purine derivatives (mercaptopurine with azathioprine) are slowed down. Because of this, you need to reduce their standard portion by 50-75%. At the same time, large portions of Allohexal inhibit the excretion of probenecid and the metabolism of theophylline.

The use of drugs together with coumarin anticoagulants requires a reduction in the portion of the latter; you also need to regularly monitor the values of blood clotting.

The dosage size of hypoglycemic agents of chlorpropamide should also be reduced.

The medicine can increase the intensity of the negative manifestations of certain drugs.

Combination with captopril increases the likelihood of developing epidermal symptoms, especially in chronic renal failure.

Administration in combination with cytostatics increases the frequency of changes in blood readings, which is why it is necessary to often take a blood test.

Taking with amoxicillin or ampicillin increases the likelihood of allergy symptoms.

Storage conditions

Allohexal must be stored in a place closed from the penetration of small children. Temperature values - no more than 25 ° С.

Shelf life

Allohexal can be used within a 5-year term from the date of manufacture of the therapeutic substance.

Analogs

The analogues of the medication are the drugs Febux and Allopurinol.