PACKAGE LEAFLET VITAMIN C

Transcription

1 PACKAGE LEAFLET VITAMIN C ATC code: A11GA01 PHARMACOTHERAPEUTIC GROUP Vitamins. COMPOSITION Ascorbic acid 100 mg or 500 mg in 1 tablet; 600 mg or 1000 mg in 1 effervescent tablet. ACTION As a redoxy-compound, ascorbic acid is a regulator of the oxidation reduction processes in the organism. It is vital for tissue respiration. Vitamin C takes part in the metabolism of carbohydrates and amino acids, in the synthesis of steroids in the suprarenal cortex and also, in the prothrombin activation. At tissue level, the primary function of ascorbic acid is connected with the synthesis of intracellular substances, including collagen, tooth and bone matrix, intracellular layer of the capillary endothelium. The preparation promotes the metabolism of folic acid, which takes part in many fundamental metabolic processes in the human organism, including that of vitamin B 12. Ascorbic acid interferes with the microsomal drug metabolism. It stimulates the synthesis of specific antimicrobial antitoxines and increases the complement content in serum, which is of importance for the immune processes. In relation to the participation in these processes, Vitamin C plays a role in the normalization of the permeability of marginal membranes, regulation of capillary permeability, inflammatory processes, desensitization, allergy, blood coagulation. 1

2 The preparation improves tissue regeneration, the functions of reticuloendothelium and immune system. Human body can not synthesize vitamin C itself, due to the lack of enzymes to take part in the final stage of its synthesis. The daily needs of Vitamin C to maintain a quantity of 3.5 mg in the body amount to mg daily. Ascorbic acid is absorbed from the intestines to the extent of 80 up to 90%. Maximum plasma concentrations are attained between the 1 st and 4 th hour. It is then distributed in all cells of the body. The concentrations of vitamin C in the leucocytes have been accepted to be representative with respect to tissue distribution. Vitamin C is metabolized to dehydroascorbic acid, oxalates and 2,3-diketogulonic acid, which are excreted in the urine. The quantity of vitamin C increases provided the daily intake excels 100 mg. normally, up to 75 mg daily is excreted with the urine, and up to 400 mg is excreted after administration of 1 g of ascorbic acid. INDICATIONS Upper-respiratory tract infections of viral or microbial origin, exhaustive acute, chronic and infectious diseases; medicamentous and gastrointestinal intoxication; protracted wound and fracture healing; stomatitis, dermatitis; haemorrhagic diathesis connected with increased capillary permeability; hyperthyroidism. Vitamin C deficiency in children, adults, and particularly in alcoholics, smokers, narcomaniacs, in case of inadequate diets, patients suffering from AIDS, cancer, diarrhea, gastric ulcer, gasroectomy, long-lasting stress conditions, patients on hemodialysis, individuals particularly at long-term exposure to low temperatures. 2

3 CONTRAINDICATIONS The relative contraindications include: erythrocyte G6PD-deficiency, hemochromatosis, thalassemia, and sideroblast anaemia, nephrolithiasis. Great care should be taken in case of toxicosis accompanying pregnancy. ADVERSE REACTIONS/SIDE EFFECTS The preparation may cause headache, nausea, vomiting, diarrhea, gripes, skin redness, increased diuresis. High dose vitamin C administration may suppress insulin liberation in pancreas and also, may bring about headache, nausea, vomiting, diarrhea, colics, skin reddening; increased diuresis; back pain. In case of sudden withdrawal of the vitamin, especially after high dose administration, symptoms of deficiency to scurvy may develop hyperkeratosis, petechia, hemorrhagia, gum inflammation, teeth falling, muscular weakness, anaemia. DRUG AND NON-DRUG INTERACTIONS Vitamin C in the microsomal drug metabolism and may alter the metabolism of a number of pharmaceuticals. It may reduce urinary ph, thus diminishing the renal tubular reabsorption of alkaline preparations, which imposes to increase the doses of the latter, especially in case of large-dose intake of the vitamin. Administration of ammonium chloride reduces the plasma levels of vitamin C. In case Vitamin C is used concurrently with atropine or barbiturates, the elimination of the preparations is mutually accelerated. Concomitant administration of Vitamin C with salicylates results in slowed elimination of the latter. Chinidin decreases the level of the vitamin, anticoagulants reduce its effect. Estrogen preparations and all oral contraceptives elevate the plasma levels of ascorbic 3

4 acid. Vitamin C administration should precede or follow that of vitamin B 12 with 2 hours, since the former decomposes the latter. Synergism is observed in case of concomitant administration with gonadotropic hormone preparations and vitamin B 1, whereas antagonism may occur with thyroxin. The preparation also interacts with aminophylline, amphothericine, chloramphenicol, chlorpromasin, erythromycin, tetracycline and prochlorperazin. Vitamin C may reduce the effects of amphetamines and tricyclic antidepressants. WARNINGS AND PRECAUTIONS Smoking reduces the assimilation of Vitamin C (higher plasma levels have been established). High-dose administration in pre-existing renal and urinary calculi should be avoided. Vitamin C may alter the results of the tests for determination of blood glucose, transaminases, LDH, bilirubin, hemorrhages in feces. PREGNANCY AND BREAST-FEEDING Provided pregnancy runs normally, the natural intake of vitamin C with nutrition diet is preferable. Administration of large Vitamin C doses during pregnancy ma give rise to symptoms of deficiency, skin reactions and allergies in the newborn infant. Ascorbic acid is excreted in the breast-milk. For that reason, in case of adequate vitamin C intake by the mother, additional intake by the nursling is not needed. EFFECTS ON ACTIVE ATTENTION, ABILITY TO DRIVE AND OPERATE MACHINES The preparation has not been established to possess any influence. 4

5 DOSAGE AND MODE OF ADMINISTRATION In the treatment of various diseases the doses of ascorbic acid for adults vary from 300 to 1000 mg daily; children 20, 50 mg to 100 mg depending on the age from 1 to 17 years of age. Tablets are taken with water. Deficiency in adults is treated with mg 3 times daily; in children mg, in the course of at least 2 weeks. Effervescent tablets are administered at a dose of 600 or 1000 mg daily. Tablets are dissolved in a cup of water and taken right away. OVERDOSAGE In case of large dose intake, increased tendency to blood coagulation, thrombophlebitis and thrombosis is observed. Administration of high doses may cause restlessness, insomnia, headache, esophagitis, diarrhea. Due to the strong urine acidification, patients with diathesis run a risk of renal and urinary calculi (cysteine, oxalate and urate) formation. PACKAGE Tablets of 100 mg in packs of 40. Tablets of 500 mg in packs of 20. Effervescent tablets of 600 mg in packs of 10. Effervescent tablets of 1000 mg in packs of 10. STORAGE In a dry place, at temperature o C, protected from light. 5