From Big Medical Encyclopedia

PYRIDOXINE (Pyridoxinum), vitamin B 6 (Vitaminum B 6 ) — the term which designate three natural forms of vitamin B 6 (so-called vitamer of B 6 ) — Pyridoxolum, piridoksal and pyridoxamine.

The item has paramount value for maintenance of processes of growth, a hemopoiesis and normal functioning of c. N of page at the person and animals. Biol, P.'s activity is connected with its turning into an organism in coenzymatical forms (see. Pyridoxal phosphate ), to-rye as a part of numerous, so-called piridoksalzavisimy, enzymes play extremely important role in processes of a metabolism and their regulation. The important role of P. in exchange is revealed folic acid (see) and regulation of biosynthesis of S-adenozil-methionine — a cofactor of the enzymes catalyzing reactions of methylation.

In medicine as medicine most often use a hydrochloride of a spirit form of vitamin B 6 — Pyridoxolum which represents colourless crystal substance bitterly - acid taste with t ° pl 203 — 206 ° (with decomposition), well water soluble, it is worse alcohol-soluble and acetone, insoluble in ether and chloroform; pH of 1% of water solution 2,5 — 3,5. Pyridoxolum is the basis, t ° pl 160 °; it is similar piridoksalyu and to pyridoxamine it easily reacts with to-tami, forming salts.

All forms P. (see fig.) are rather stable: they do not collapse during the autoclaving in 2 N solution a chamois to - you and rezistentna to oxygen of air, but are very sensitive to effect of light, especially at neutral and alkaline pH values of the environment. Vitamera characteristic absorption spectrums and fluorescence have B6, to-rye depend on ion concentration of H + in the environment.

The majority of microorganisms and plants are capable to synthesize P.; for animals and the person it is an irreplaceable factor of food (see. Vitamins ). An important condition of utilization and P.'s deposition in fabrics — its phosphorylation catalyzed by enzyme liridoksalkinazy (KF 2. 7. 1. 35). An end product of exchange of P. in an organism — biologically inactive 4-piridoksilovy to - that.

In 1976 by Yu. V. Bukin and A. D. Ivanova it was established that individual need of children for P. for normal formation of functions of c. the N of page is defined considerably by activity of a pyridoxal kinase in tissue of the developing brain. Inherited or functional disorders of exchange of P. lead at children to heavy disturbances of activity of c. N of page (see. Enzymopathies ). P.'s transformation into coenzymatical forms is broken at atherosclerosis and some other patol, states, and also at alcoholism.

The daily need for P. at the adult normal makes apprx. 2,0 — 2,5 mg. At P.'s lack of food signs of Wb hypovitaminosis develop. At children B6-gi-povptaminoz it is shown by a growth inhibition, went. - kish. frustration, hyperexcitability, epileptiform spasms, hypochromia macrocytic anemia; at adults — dermatitis, loss of appetite, nausea, vomiting, a depression, sleeplessness.

Meat and an offal, especially a liver, and also fish, eggs, bread from coarse flour, potatoes and carrots are full-fledged sources of P. In the course of culinary processing P.'s maintenance in meat decreases by 20 — 35%; during the smoking and conservation of meat — more than for 50%. In the course of preparation of the condensed or powdered milk of loss of P. reach 30%. P.'s maintenance in milk (in glass balloons on solar to light) in 2 hours can decrease by 50% and more.

For determination of content of P. and its various forms use spektrofotometrichesky, flyuori-metric and mikrobiol, methods. Division of individual vitamer of Wb is made by means of a chromatography and an electrophoresis.

Antitubercular drugs — izonikotinilgidrazid (Ftivazidum) and an antibiotic Cycloserinum belong to number of antagonists, important for medical practice, and P.'s antimetabolites. Nek-ry antimetabolites of P. draw attention of researchers as possible antineoplastic means.

Pyridoxine as drug

Pyridoxine (Pyridoxinum; synonym: Adermin, Beadox, Bedoxin, Pyrivitol, Vitaminum B6 etc.) — the vitamin drug representing a hydrochloride of one of vitamer of B 6 Pyridoxolum.

At intake of P. it is quickly soaked up from a small bowel in blood, and in a liver and some other bodies turns into coenzymatical forms — piridoksal-5' - phosphate and pyridoxyamine-5 '-phosphate. During further biotransformation of P. the metabolite — 4-piridoksilovy to - that which is brought out of an organism through kidneys is formed its inactive in biol, the relation. At P.'s introduction in high doses it can partially be allocated from an organism with urine in not changed look.

Apply The item for prevention and treatment of B6 hypovitaminosis, during the feeding of children dry milk blends, toxicoses of pregnant women in the first half of pregnancy, sideroakhrestichesky and macrocytic anemias and leukopenias of various etiology, diseases of a nervous system (radiculitises, neuritis, neuralgia, posttraumatic tserebropatiya, viral encephalitis, parkinsonism, a hysterical chorea, Littl's disease). Appoint P. also for prevention sea and aeroembolism and as means for prevention and stopping of attacks of disease of Menyer. There are observations testimonial of P.'s efficiency at atherosclerosis and a diabetes mellitus, acute and hron, hepatitises. The item has ability to increase a diuresis. However P.'s use in high doses at severe damages of a liver can work depressing on its function.

In Dermatolum, the practician P. appoint at neurodermatitises, psoriasis, exudative diathesis, seborrhea - on - dobnykh and not seborrheal dermatitis.

The item warns or reduces the by-effects (especially polyneurites) which are observed at prolonged use of Tubazidum, Ftivazidum, Cycloserinum and other antituberculous remedies.

Item. appoint inside after food, and also enter subcutaneously, intramusculary or intravenously. Parenterally P. apply for the purpose of obtaining bystry effect or at impossibility of intake (e.g., at vomiting or disturbance of processes of absorption of P. in intestines).

For prevention of Vb-gipovita-minoza P. appoint the adult 0,002 — 0,005 g a day, to children — depending on age. Daily to lay down. the dose (inside or parenterally) makes 0,05 — 0,1 g on 1 — 2 reception. The course of treatment proceeds 1 — 2 month depending on disease severity and from efficiency of treatment.

At P.'s anemias appoint inside on 0,1 g daily or 0,1 2 intramusculary 2 times a week. Reasonablly during oral administration of P. to treat (parenterally) cyanocobalamine (see), folic to - that, Riboflavinum (see).

For the prevention of neuritis at reception of Tubazidum, Ftivazidum or other derivatives of hydrazide isonicotinic to - you P. is appointed as the proofreader of by-effects on 0,005 — 0,01 g a day.

However P. with these pharmaceuticals forms inactive connections therefore the interval between reception of these drugs and rat anti-acrodynia factor shall be not less than 5 — 6 hour.

At P.'s parkinsonism enter on 2 ml 5% of solution intramusculary; on a course of treatment — 20 — 25 injections. If necessary the course of treatment is repeated in 2 — 3 months.

In some cases at P.'s use there can be allergic reactions. Due to the possible increase in gastric acidity it is necessary to appoint with care P. the patient with a peptic ulcer of a stomach and duodenum, and also with a serious illness of a liver and the patient with a myocardial infarction. It is impossible to appoint P. together with left Don, and also to mix in one syringe P. with antituberculous remedies, cyanocobalamine and thiamin.

Forms of release: tablets on 0,002; 0,005 and 0,01 g; ampoules on 1 ml of 1% and 5% of solution. Store in banks of orange glass in the cool, protected from light place.

As medicine use as well a coenzymatical form of vitamin B 6 — pyridoxal phosphate. It is applied at the same diseases, as P., and also at states at which resistance to the Item is observed.

Among derivative P. in medical practice apply his disulfide homolog Pyriditolum. Chemical modification of a molecule P. led to the fact that Pyriditolum lost B 6 - vitamin activity, but gained psychotropic properties, it exerts the normalizing impact on separate reactions of metabolism of cells of a brain.

Pyriditolum is shown at the block and superficial depressions irrespective of nosological accessory (presenile and senile syndromes, maniac-depressive psychosis, an alarming and depressive syndrome, the erased polymorphic sub depressions, the loony stenopodobny and hypochiondrial frustration) which are combined with vascular insufficiency and other organic changes of c. N of page; at schizophrenia and a psychoorganic syndrome, at asthenic states, an adynamia, neurosis-like disorders of organic genesis, a vegetoangiodistoniya, migraines, at traumatic and vascular encephalopathy, the residual phenomena after the postponed neuroinfections, cerebral atherosclerosis, effects of disturbance of cerebral circulation; as the proofreader of antipsychotic therapy for improvement of portability of some psychotropic drugs, stopping of «medicinal» parkinsonism and other neurologic symptomatology.

To children Pyriditolum is recommended to appoint at a delay of mental development, tserebroasteniche-sky frustration, mental retardation, encephalopathies.

Appoint Pyriditolum inside in 15 — 30 min. after food; it is recommended to accept it 2 — 3 times a day, the last reception — not later 17th hour. A single dose for adults from 0,1 g to 0,3 g; daily — from 0,2 g to 0,6 g. At selection of an optimum therapeutic dose individual portability of drug is considered. It is desirable to appoint in the first 10 days the adult Pyriditolum in a dose of 0,3 — 0,4 g a day, and then depending on effect and portability of drug to raise or reduce a dosage. A course of treatment of 1 — 3 month, in some cases — 6 — 8 months. If necessary recommend repeated courses in 1 — 6 month.

To children depending on age drug is appointed in a daily dose: from 1 year to 3 years — 0,05 — 0,1 g, from 4 to 10 years — 0,1 — 0,15 g, from 11 to 14 years — 0,2 — 0,3 g. In the first 10 days Pyriditolum is recommended to be accepted only in the morning and in the afternoon and in smaller doses. Then morning and day doses are increased and add the third reception. Duration of a course of treatment for children of 2 weeks up to 3 months, most often appoint a two-month course of treatment. In 3 — 6 months repeated courses are possible.

Contraindications: the expressed psychomotor excitement, epilepsy, conditions of the increased risk concerning development of a tetany.

Form of release: tablets, coated, on 0,05; 0,1; 0,2 g.

Bibliography: Vitamins, under the editorship of M. I. Smirnov, e. 214, M., 1974; E f-remov V. V. K to a question of security with Riboflavinum and rat anti-acrodynia factor and of need in them of the person, Vopr, pitas., No. 4, page 3, 1979; Clinical pharmacology, under the editorship of V. V. Zakusov, page 353, M., 1978; Molecular bases of pathology, under the editorship of V. N. Orekhovich, page 268, M., 1966; Chemistry and biology of the pyridoxaleft catalysis, under the editorship of A. E. Braunstein, etc., page 432, M., 1968; Experimental vitaminology, under the editorship of Yu. M. Ostrovsky, page 385, Minsk, 1979; In and-kin Y. V., Draudin-Krylen-ko V. A. a. K o r y t n y k W. Potentiating action of 4-vinylpyridoxal on inhi-l) ition of serine transhydroxymethylase by D-cyeloserine and its dimer, Biochem. Pharmacol., v. 28, p. 1669, 1979.

Yu. V. Bukin; V. M. Avakumov (pharm.).