Ascorbic acid

Pharmacological properties

ascorbic acid (vitamin c) has pronounced reducing properties. It belongs to the group of water-soluble vitamins. participates in redox reactions, regulates carbohydrate metabolism, affects the metabolism of aromatic amino acids, metabolism of thyroxin, the biosynthesis of catecholamines, steroid hormones and insulin, is necessary for blood coagulation, synthesis of collagen and procollagen, regeneration of connective and bone tissue. improves capillary permeability. promotes the absorption of iron in the intestine and is involved in the synthesis of hemoglobin. increases nonspecific resistance of the body, has an antidote property. deficiency of vitamin C in food leads to the development of hypo- and vitamin deficiency c, since this vitamin is not synthesized in the body.

Pharmacokinetics Absorption of ascorbic acid occurs mainly in the small intestine. The absorption process can be disturbed with intestinal dyskinesia, enteritis, achilia, helminthic infestation, giardiasis, as well as the use of alkaline drinks, fresh fruit and vegetable juices. C_maxa drug in plasma after oral administration is achieved after 4 hours. It easily penetrates into white blood cells, platelets, and then into all tissues; deposited in the back of the pituitary gland, adrenal cortex, ocular epithelium, intermediate cells of the seminal glands, ovaries, liver, brain, spleen, pancreas, lungs, kidneys, intestinal wall, heart, muscles, thyroid gland. It is metabolized mainly in the liver, to deoxy-ascorbic acid and subsequently to oxaloacetic and diketogulonic acids. Unchanged ascorbate and metabolites are excreted in urine, feces, and also pass into breast milk. When used in high doses, when the concentration in the blood plasma reaches 1.4 mg / dl, excretion is sharply enhanced, and increased excretion may persist after cessation of use.

Indications

Prevention and treatment of vitamin C deficiency. providing the body’s increased need for vitamin C during the growth period, during pregnancy and lactation; with increased physical and mental stress, with infectious diseases and intoxication, hemorrhagic diathesis, in complex therapy for bleeding (nasal, pulmonary, uterine); with radiation sickness, Addison’s disease, an overdose of anticoagulants, with soft tissue injuries and infected wounds that slowly heal, bone fractures.

Application

Inside after a meal.

Adults and children over the age of 14 years should take 1-2 tablets (50-100 mg) per day for prevention, children 3-14 years old - 1 tablet (50 mg) per day.

Therapeutic doses for children over 14 years of age and for adults are 1-2 tablets (50-100 mg) 3-5 times a day, for children aged 3-7 years - 1-2 tablets (50-100 mg ) 2-3 times a day, at the age of 7-10 years - 2 tablets (100 mg) 2-3 times a day, at the age of 10-14 years - 2-3 tablets (100-150 mg) 2-3 times per day.

Pregnant women and women after childbirth and with low levels of vitamin C in breast milk should take 6 dragees (300 mg) per day for 10-15 days, then for prevention - 2 dragees (100 mg) per day for the entire period of breastfeeding.

The duration of treatment depends on the nature and course of the disease and is determined individually by the doctor.

Contraindications

Hypersensitivity to ascorbic acid or any of the excipients of the drug, thrombosis, tendency to thrombosis, thrombophlebitis, diabetes mellitus, severe kidney disease, urolithiasis (with 1 g / day), intolerance to fructose, glucose-galactose malabsorption syndrome.

Side effects

From the digestive tract: when applying 1 g / day - irritation of the mucous membrane of the digestive tract, heartburn, nausea, vomiting, diarrhea.

On the part of the kidneys and urinary system: damage to the glomerular apparatus of the kidneys, crystalluria, the formation of urate, cystine and / or oxalate calculi in the kidneys and urinary tract.

On the part of the immune system: Quinckes edema, sometimes anaphylactic shock in the presence of sensitization.

On the part of the skin and subcutaneous tissue: skin rash, itching, urticaria, eczema.

From the endocrine system: damage to the insular apparatus of the pancreas (hyperglycemia, glucosuria) and impaired glycogen synthesis up to the development of diabetes mellitus.

From the cardiovascular system: AH, myocardial dystrophy.

From the blood system and lymphatic system: thrombocytosis, hyperprothrombinemia, thrombosis, erythrocytopenia, neutrophilic leukocytosis; in patients with deficiency of glucose-6-phosphate dehydrogenase, blood cells can cause erythrocyte hemolysis, hemolytic anemia (in patients with deficiency of glucose-6-phosphate dehydrogenase).

From the nervous system: increased irritability, sleep disturbance, headache, sensation of fever, fatigue.

From the side of metabolism: metabolic imbalance of zinc, copper.

special instructions

When using the drug in high doses and for a long time, it is necessary to control the function of the kidneys and the level of hell, as well as the function of the pancreas. it should be used with caution in patients with a history of kidney disease.

With urolithiasis, the daily dose of ascorbic acid should not exceed 1 g.

Do not prescribe the drug in high doses to patients with increased blood coagulation.

Since ascorbic acid increases iron absorption, its use in high doses can be dangerous for patients with hemochromatosis, thalassemia, polycythemia, leukemia and sideroblastic anemia. Patients with a high iron content in the body should use the drug in minimal doses.

The simultaneous use of the drug with alkaline drink reduces the absorption of ascorbic acid, so you should not drink it with alkaline mineral water. Also, the absorption of ascorbic acid can be impaired with intestinal dyskinesia, enteritis and achilia.

It is used with caution for treatment in patients with glucose-6-phosphate dehydrogenase deficiency.

Ascorbic acid as a reducing agent can affect the results of various laboratory studies, for example, in determining the blood glucose, bilirubin, transaminase activity, LDH.

Since ascorbic acid has a mild stimulating effect, it is not recommended to use the drug at the end of the day. In connection with the stimulating effect of ascorbic acid on the formation of corticosteroid hormones, the use of the drug in high doses requires monitoring of renal function and blood pressure.

Use during pregnancy or lactation. The drug can be used during pregnancy or breastfeeding in accordance with the dosage recommendations and doctors prescription. Carefully adhere to the recommended doses and do not exceed them.

Children. The drug is used in children over the age of 3 years.

The ability to influence the speed of reactions when driving vehicles or working with other mechanisms. Does not affect.

Interactions

Oral ascorbic acid increases the absorption of penicillin, tetracycline, iron; promotes the absorption of aluminum in the intestine, which should be considered with simultaneous treatment with antacids containing aluminum.

The combined use of vitamin C and deferoxamine increases tissue toxicity of iron, especially in the heart muscle, which can lead to decompensation of the circulatory system. Vitamin C can be used only 2 hours after injection of deferoxamine.

Long-term use in high doses by persons using disulfiramine inhibits the disulfiram / alcohol reaction.

High doses of the drug reduce the effectiveness of tricyclic antidepressants, antipsychotics - phenothiazine derivatives, tubular reabsorption of amphetamine, disrupt the excretion of mexiletine by the kidneys, affect the absorption of vitamin B₁₂.

Ascorbic acid increases the overall clearance of ethyl alcohol.

The drug reduces the toxicity of sulfonamide drugs, as well as the effectiveness of heparin and indirect anticoagulants.

Vitamin C enhances the excretion of oxalates in the urine, thus increasing the risk of formation of oxalate stones in the urine, and increases the risk of crystalluria during treatment with salicylates.

Medicines of the quinoline series, calcium chloride, salicylates, corticosteroids with prolonged use reduce the depot of ascorbic acid in the body.

The absorption of ascorbic acid is reduced with the simultaneous use of oral contraceptives, the use of fruit or vegetable juices, alkaline drink.

Overdose

Ascorbic acid is well tolerated. it is a water-soluble vitamin, its excessive amount is excreted in the urine.

Symptoms With prolonged use of vitamin C in high doses, inhibition of the function of the insular apparatus of the pancreas is possible, which requires monitoring the state of the latter. An overdose can lead to a change in renal excretion of ascorbic and uric acids during urinary acetylation with the risk of precipitation of oxalate calculi.

The use of the drug in high doses can lead to vomiting, nausea or diarrhea, which disappear after its withdrawal.

Treatment. Symptomatic Therapy

Storage conditions

In the original packaging at a temperature not exceeding 25 ° C.