Summary of medicine characteristics - ASCORBIC ACID 500 MG TABLETS, VODEXO 500 MG TABLETS
1 NAME OF THE MEDICINAL PRODUCT
Ascorbic Acid 500mg Tablets
Vodexo 500mg Tablets
2 QUALITATIVE AND QUANTITATIVE COMPOSITION
Each tablet contains 500mg ascorbic acid
Excipients with known effect: contains 3.00 mg/tablet lactose monohydrate
For the full list of excipients, see section 6.1.
3 PHARMACEUTICAL FORM
White to off-white uncoated tablets.
Ascorbic Acid 500mg Tablets are 12.5 mm, white to off-white, plain round, biconvex tablets.
4 CLINICAL PARTICULARS
4.1 Therapeutic indications
Vitamin C deficiency
Treatment of scurvy
4.2 Posology and method of administration
Posology
Adults: Therapeutic use – at least 250mg daily in divided doses.
Maximum of 1000mg daily.
Elderly: As for other adults. As the dietary intake of vitamin C may be less in
the elderly, they have greater risk of presenting with vitamin C deficiency.
Method of administration
For oral administration.
4.3 Contraindications
Ascorbic acid should not be given to patients with hyperoxaluria.
Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
4.4 Special warnings and precautions for use
Increased intake of ascorbic acid over a prolonged period may result in increased renal clearance of ascorbic acid, and deficiency may result if the intake is reduced or withdrawn rapidly. (See section 4.8)
Ascorbic acid may interfere with tests and assays for urinary glucose, giving falsenegative results with methods utilising glucose oxidase with indicator (e.g. Labstix, Testape) and false- positive results with neocuproin methods.
Estimation of uric acid by phosphotungstate or uricase with copper reduction and measurement of creatinine in non-deproteinised serum may also be affected.
High doses of ascorbic acid may give false-negative readings in faecal occult blood tests.
This product contains lactose. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.
4.5 Interactions with other medicinal products and other forms of interaction
Ascorbic acid increases the renal excretion of amphetamine. The plasma concentration of ascorbate is decreased by smoking and oral contraceptives.
Ascorbic acid increases the absorption of iron.
Concomitant administration of aspirin and ascorbic acid may interfere with absorption of ascorbic acid. Renal excretion of salicylate is not affected and does not lead to reduced anti-inflammatory effects of aspirin.
Concomitant administration of aluminium-containing antacids may increase urinary aluminium elimination. Concurrent administration of antacids and ascorbic acid is not recommended, especially in patients with renal insufficiency.
Co-administration with amygdalin (a complementary medicine) can cause cyanide toxicity.
Concurrent administration of ascorbic acid with desferrioxamine enhances urinary iron excretion. Cases of cardiomyopathy and congestive heart failure have been reported in patients with idiopathic haemochromatosis and thalassaemias receiving desferrioxamine who were subsequently given ascorbic acid. Ascorbic acid should be used with caution in these patients and cardiac function monitored.
Ascorbic acid may interfere with biochemical determinations of creatinine, uric acid and glucose in samples of blood and urine.
4.6 Fertility, pregnancy and lactation
Pregnancy
For ascorbic acid no clinical data on exposed pregnancies are available. Animal studies do not indicate direct or harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development. Pregnant women should exercise caution.
Breast-feeding
Ascorbic acid is excreted in breast milk. Though again caution should be exercised, no evidence exists suggesting such excretion is hazardous to the infant.
4.7 Effects on ability to drive and use machines
On the basis of the product’s pharmacodynamic profile and reported adverse events, ascorbic acid has no known effect on an individual’s ability to drive or operate machinery.
4.8 Undesirable effects
Nervous system disorders: headache. Vascular disorders: flushing
Gastrointestinal disturbances: nausea, vomiting and stomach cramps. Large doses of ascorbic acid may cause diarrhoea.
Skin and subcutaneous tissue disorders: redness of skin.
Renal and urinary disorders: Patients known to be at risk of hyperoxaluria should not ingest ascorbic acid doses exceeding 1g daily as there may be increased urinary oxalate excretion. However, such risk has not been demonstrated in normal, nonhyper oxaluric individuals.
Increased intake of ascorbic acid over a prolonged period may result in increased renal clearance of ascorbic acid, and deficiency may result if the intake is reduced or withdrawn rapidly. Doses of more than 600mg daily have a diuretic effect.
Ascorbic acid has been implicated in precipitating haemolytic anaemia in certain individuals deficient of glucose-6-phosphate dehydrogenase.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
4.9 Overdose
Symptoms
At doses of over 3gm per day unabsorbed ascorbic acid is mainly excreted unmetabolised in the faeces. Absorbed ascorbic acid additional to the body’s needs is rapidly eliminated. Large doses of ascorbic acid may cause diarrhoea and the formation of renal oxalate calculi. Symptomatic treatment may be required.
Ascorbic acid may cause acidosis or haemolytic anaemia in certain individuals with a deficiency of glucose 6-phosphate dyhydrogenase. Renal failure can occur with massive ascorbic acid overdosage.
Management
Gastric lavage may be given if ingestion is recent otherwise general supportive measures should be employed as required
5.1 Pharmacodynamic properties
ATC Code of Ascorbic Acid : A11G A01
Ascorbic acid, coupled with dehydroascorbic acid to which it is reversibly oxidised, has a variety of functions in cellular oxidation processes. Ascorbic acid is required in several important hydroxylations, including the conversion of proline to hydroxyproline (and thus in collagen formation e.g. for intercellular substances and during wound healing); the formation of the neurotransmitters 5-hydroxytryptamine from tryptophan and noradrenaline from dopamine, and the biosynthesis of carnatine from lysine and methionine. Ascorbic acid appears to have an important role in metal ion metabolism, including the gastrointestinal absorption of iron and its transport between plasma and storage organs. There is evidence that ascorbic acid is required for normal leucocyte functions and that it participates in the detoxification of numerous foreign substances by the hepatic microsomal system. Deficiency of ascorbic acid leads to scurvy, which may be manifested by weakness, fatigue, dyspnoea, aching bones, perifollicular hyperkeratoses, petechia and ecchymosis, swelling and bleeding of the gums, hypochromic anaemia and other haematopoietic disorders, together with reduced residence to infections and impaired would healing.
5.2 Pharmacokinetic properties
Ascorbic acid is well absorbed from the gastro-intestinal tract, and is widely distributed to all tissues. Body stores of ascorbic acid normally are about 1.5g. The concentration is higher in leucocytes and platelets than in erythrocytes and plasma. Ascorbic acid additional to the body’s needs, generally amounts above 200mg daily, is rapidly eliminated; unmetabolised ascorbic acid and its inactive metabolic products are chiefly excreted in the urine. The amount of ascorbic acid excreted unchanged in the urine is dose-dependent and may be accompanied by mild diuresis.
5.3 Preclinical safety data
6 PHARMACEUTICAL PARTICULARS
6.2 Incompatibilities
None known
6.3 Shelf life
36 months
6.4 Special precautions for storage
Do not store above 25°C. Store in the original package to protect from light and moisture.
6.5 Nature and contents of container
Blister strips of 14 tablets each consisting of 250 |im white PVC, a 90 g/m2 PVDC layer and 20 |im hard temper aluminium foil, contained in a carton. Total pack size of 28 tablets per carton.
6.6 Special precautions for disposal
6.6 Special precautions for disposalAlways close the cap securely after use.
7 MARKETING AUTHORISATION HOLDER
Athlone Pharmaceuticals Limited
Ballymurray
Co. Roscommon
Ireland
8 MARKETING AUTHORISATION NUMBER(S)
PL 30464/0057