ASCORBIC ACID TABLETS BP 500 MG - summary of medicine characteristics

1 NAME OF THE MEDICINAL PRODUCT

Ascorbic Acid Tablets BP 500 mg

2 QUALITATIVE AND QUANTITATIVE COMPOSITION

Each tablet contains 500.0 mg of ascorbic acid.

For excipients, see 6.1.

3 PHARMACEUTICAL FORM

Tablet.

Ascorbic Acid Tablets BP 500 mg are presented as white to off-white normal convex tablets

4 CLINICAL PARTICULARS

4.1 Therapeutic indications

Prevention and treatment of scurvy.

4.2 Posology and method of administration

Adults and children over 6 years:

Prophylactic: 25 – 75 mg daily.

Note: this unit dosage form is unsuitable for prophylactic use.

Therapeutic: not less than 250 mg daily in divided doses.

Children under 6 years:

This unit dosage form is unsuitable for children under 6 years.

Elderly:

Dosage same as for adults.

Route of administration

Oral.

4.3 Contraindications

Hypersensitivity to ascorbic acid or to any of the excipients.

Hyperoxaluria.

4.4 Special warnings and precautions for use

Excessive use of chewable ascorbic acid tablets may cause breakdown of enamel and increased incidence of caries.

Increased intake of ascorbic acid over a prolonged period may result in an increase in renal clearance of ascorbic acid and deficiency may result if it is withdrawn rapidly. Large doses are associated with the formation of renal calcium oxalate calculi.

The administration of therapeutic doses of ascorbic acid may interfere with Clinistix test for glucosuria giving a false negative result.

4.5 Interaction with other medicinal products and other forms of interaction

Concurrent use of ascorbic acid with barbiturates or primidone may increase the urinary excretion of ascorbic acid.

Concurrent use with cellulose sodium phosphate may result in metabolism of ascorbic acid to oxalate.

Concurrent use of desferrioxamine with ascorbic acid enhances tissue iron toxicity especially in the heart.  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

haemochromotosis and thalassaemias  receiving  desferrioxamine  who were

subsequently given ascorbic acid. Ascorbic acid should be used with caution in these patients and cardiac function monitored.

Concurrent use of disulfiram with ascorbic acid especially with chronic use or in high doses may interfere with the disulfiram-alcohol interaction.

Marked acidification of urine resulting from use of large doses of ascorbic acid may accelerate the renal excretion of mexiletine if administered concurrently.

Concomitant administration of aspirin and ascorbic acid may interfere with absorption of ascorbic acid. Concurrent use of salicylates with ascorbic acid may increase the urinary excretion of ascorbic acid. However, 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.

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

Ascorbic acid crosses the placental barrier and is excreted in breast milk. Studies in animals and humans have not been conducted. Problems have not been documented with the intake of normal daily requirements during pregnancy and lactation. However, ingestion of large quantities during pregnancy may result in increased requirements and scurvy in the neonate. Ascorbic acid in doses greater than 1 g should not be administered during pregnancy as the effect of large doses on the foetus is not known.

No problems are anticipated with the administration of ascorbic acid tablets during lactation.

4.7 Effects on ability to drive and use machines None.

4.8 Undesirable effects

Ascorbic acid is usually well tolerated. High doses (greater than 1 g per day) may result in diarrhoea. Other effects are flushing or redness of the skin, headache, mild increase in urination with doses greater than 600 mg per day, nausea, vomiting, stomach cramps and occasionally back pain. Ascorbic acid may cause haemolytic anaemia in certain individuals with a deficiency of glucose-6-phosphate dehydrogenase.

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.

4.9 Overdose

Adverse effects are not normally expected from an acute overdose of the watersoluble vitamin.

Ascorbic acid may cause acidosis or haemolytic anaemia in certain individuals with a deficiency of glucose 6-phosphate dehydrogenase. Renal failure can occur with massive ascorbic acid overdosage.

Gastric lavage may be given if ingestion is recent otherwise general supportive measures should be employed as required.

5 PHARMACOLOGICAL PROPERTIES

5.1 Pharmacodynamic properties

Pharmacotherapeutic group: Vitamins – Ascorbic acid (vitamin C), plain

ATC code: A11GA

Ascorbic acid is a water-soluble vitamin essential for the synthesis of collagen and intercellular material. It is involved in some oxidation-reduction reactions. It is also involved in metabolism of phenylalanine, tyrosine, folic acid and iron; utilisation of carbohydrate; synthesis of lipids and proteins; and preservation of blood vessel integrity.

5.2 Pharmacokinetic properties

Ascorbic acid is readily absorbed from the gastro-intestinal tract mainly the jejunum. Large quantities limit the absorption. Binding to plasma proteins is low approximately 25%. It is widely distributed in the body tissues. Biotransformation occurs in the liver.

The amount of ascorbic acid in the body in health is about 1.5 g. The concentration is higher in leucocytes and platelets than in erythrocytes and plasma. In deficiency states the concentration in leucocytes decline later and at a slower rate than the concentration in plasma.

It is reversibly oxidised to dehydroascorbic; some is metabolised to ascorbate-2-sulphate, which is inactive, and oxalic acid which is excreted in the urine. Ascorbic acid in excess of the body’s need is also rapidly eliminated in the urine. Ascorbic acid crosses the placental barrier and is distributed into breast milk. It is removed by haemodialysis.

5.3 Preclinical safety data

There are no pre-clinical data of relevance to the prescriber which are additional to that already included in other sections of the SPC.

6 PHARMACEUTICAL PARTICULARS

6.1 List of excipients

Lactose

Magnesium stearate Thixin R

Sodium starch glycollate Microcrystalline cellulose Colloidal silicon dioxide

6.2 Incompatibilities

None.

6.3 Shelf life

Plastic containers:

Blister packs:

36 months (3 years), as packaged for sale

24 months (2 years), as packaged for sale

6.4 Special precautions for storage

Keep out of the reach of children.

Protect from heat, light and moisture.

6.5 Nature and contents of container

1. Opaque plastic containers (securitainers) fitted with plastic caps with a packaging inclusion of a silica gel desiccant pack.

Pack sizes are 28, 30, 42, 50, 56, 60, 84, 90, 100, 112, 250, 500 or 1000 tablets.

2. Opaque plastic containers composed of either high density polypropylene or high density polyethylene with a tamper evident or child resistant tamper evident closure composed of high density polyethylene with a packaging inclusion of standard polyether foam or polyethylene or polypropylene made filler and a silica gel desiccant pack.

Pack sizes are 28, 30, 42, 50, 56, 60, 84, 90, 100, 112, 250, 500 or 1000 tablets.

3. Blister packs of aluminium/opaque PVC packed in printed boxboard cartons.

Pack sizes are 28, 30, 56, 60, 84, 90 or 112 tablets.

Not all pack sizes may be marketed.

6.6 Special precautions for disposal

No special instructions for use/handling.

7 MARKETING AUTHORISATION HOLDER

Crescent Pharma Ltd

Units 3 & 4, Quidhampton Business Units

Polhampton Lane

Overton

Hampshire

RG25 3ED

8 MARKETING AUTHORISATION NUMBER(S)

PL 20416/0192

9 DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATION

12 January 2004