This medicine is used for:

Posology

Adults:

1. Monotherapy: For primary prevention of coronary heart disease and to reduce cholesterol: After initial introduction over a three to four week period, 3 to 6 sachets per day, administered either as a single daily dose or in divided doses up to four times daily, according to dosage requirements and patient acceptability. Dosage may be modified according to response and can be increased to 9 sachets per day if necessary.

Occasional slight gastrointestinal upsets, e.g. constipation, may occur when starting Colestyramine. These usually pass with continued usage of Colestyramine and are minimised by starting therapy gradually.

Combination therapy

The cholesterol-lowering effect of colestyramine on total and LDL-cholesterol is enhanced when it is combined with an HMG-CoA reductase inhibitor (e.g. pravastatin, simvastatin, lovastatin). Enhanced lowering of LDL-cholesterol is also seen with combined nicotinic acid/colestyramine therapy. There is also evidence to support the addition of colestyramine to gemfibrozil therapy in order to further lower LDL-cholesterol in patients with high LDL- cholesterol and triglycerides and low HDL-cholesterol.

2. To relieve pruritus: One or two sachets daily are usually sufficient.

3. To relieve diarrhoea: As for reduction of cholesterol but it may be possible to reduce this dosage. In all patients presenting with diarrhoea induced by bile acid malabsorption, if a response is not seen within 3 days, then alternative therapy should be initiated.

Doses of more than 24 g a day of colestyramine resin may interfere with normal fat absorption.

Paediatric population

Children 6 - 12 years:

The initial dose is determined by the following formula:

Subsequent dosage adjustment may be necessary where clinically indicated.

To minimise potential gastrointestinal side effects, it is desirable to begin all therapy in children with one dose of this medicine daily. The dosage is then increased gradually, every five to seven days to the desired level for effective control.

Children under 6 years:

Colestyramine should not be used in children under 6 years. There are no data to support its use.

Colestyramine should not be used in patients with exudative or bloody diarrhoea.

Elderly:

No dosage adjustment is necessary.

Method of administration

As a precautionary measure, where concurrent drug therapy exists then such drugs should be administered at least one hour before or 4-6 hours after taking this medicine.

Colestyramine should not be taken in its dry form.

Colestyramine should be administered mixed with water or a suitable liquid, such as fruit juice, and stirred to a uniform consistency.

Colestyramine may also be mixed with skimmed milk, thin soups, pulpy fruits with high moisture content, e.g. apple sauce, etc.

The suggested time of administration is mealtime, but this may be modified to avoid interference with absorption of other medications.

Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.

In patients with complete biliary obstruction, since this medicine cannot be effective where bile is not secreted into the intestine.

Before instituting therapy with Colestyramine, diseases contributing to increased blood cholesterol such as hypothyroidism, diabetes mellitus, nephrotic syndrome, dysproteinaemias and obstructive liver disease should be investigated and specifically treated. In addition, prior to instituting therapy with Colestyramine, an attempt should be made to control serum cholesterol by appropriate dietary regimen, weight reduction, and the treatment of any underlying disorder which might be the cause of the hypercholesterolaemia. Serum cholesterol levels should be determined frequently during the first few months of therapy and periodically thereafter. A favourable trend in cholesterol reduction should occur during the first month of Colestyramine therapy. The therapy should be continued to sustain cholesterol reduction. Serum triglyceride levels should be measured periodically to detect whether significant changes have occurred.

Reduction of serum folate concentrations has been reported in children with familial hypercholesterolaemia. Supplementation with folic acid should be considered in these cases.

Since Colestyramine may interfere with the absorption of fat-soluble vitamins, the diet may require supplementation with Vitamins A, D and K during prolonged high dose administration.

Chronic use of this medicine may be associated with increased bleeding tendency due to hypoprothrombinaemia associated with Vitamin K deficiency. This will usually respond promptly to parenteral Vitamin K administration. Recurrences can be prevented by oral administration of Vitamin K.

Since colestyramine may bind other drugs given concurrently, the interval between the administration of colestyramine and other medication should be as great as is feasible. Patients should take other drugs at least one hour before or four to six hours after colestyramine to avoid impeding their absorption.

There is a possibility that prolonged use of colestyramine resin in high doses may produce hyperchloremic acidosis, since it is the chloride form of an anion exchange resin. This is especially true in younger and smaller patients where the relative dosage may be higher as well as in patients with renal impairment.

Colestyramine may produce or aggravate pre-existing constipation or related conditions, such as haemorrhoids. In patients with constipation, the dosage of colestyramine should be decreased, since it may produce impaction. In patients presenting with clinically symptomatic coronary artery disease, where straining of the stool is to be avoided, the dosage of this medicine should be titrated to avert constipation.

This medicine contains 3.79 g sucrose in each sachet. This should be taken into account in patients with diabetes mellitus.

Patients with rare hereditary problems of fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.

This medicine contains 97.5 mg propylene glycol (as alginate) in each sachet.

If the patient is less than 5 years old, co-administration with any substrate for alcohol dehydrogenase such as ethanol may induce adverse effects. For propylene glycol doses exceeding 50 mg/kg/day, medical monitoring is required in patients with impaired renal or hepatic function.

Colestyramine may delay or reduce the absorption of certain drugs (such as digitalis, tetracycline, chlorothiazide, warfarin and thyroxine). The discontinuation of Colestyramine could pose a hazard to health if a potentially toxic drug such as digitalis has been titrated to a maintenance level while the patient was taking this medicine. The response to concomitant medication should be closely monitored and appropriate adjustments made if necessary.

Colestyramine may interfere with the pharmacokinetics of drugs that undergo enterohepatic recirculation. Colestyramine in combination with spironolactone may increase the potential for the development of hyperchloraemic acidosis.

Patients should take other drugs at least one hour before or 4-6 hours after taking this medicine to minimise possible interference with their absorption.

Tabulated list of Colestyramine drug-drug interactions:

The safety of colestyramine in pregnancy and lactation has not been established and the possibility of interference with absorption of fat-soluble vitamins should be considered.

This medicine has no or negligible influence on the ability to drive and use machines.

Frequency categories are defined according to the following convention: very common (≥ 1/10), common (≥ 1/100 to < 1/10), uncommon (≥ 1/1,000 to < 1/100), rare (≥ 1/10,000 to < 1/1,000), very rare (< 1/10,000), not known (cannot be estimated from the available data).

The most common adverse reaction is constipation. Predisposing factors for most of these complaints when this medicine is used as a cholesterol lowering agent are: high dose and increased age (more than 60 years old). Most instances of constipation are mild, transient and controlled with conventional therapy. Some patients require a temporary decrease in dosage or discontinuation of therapy.

Tabulated list of adverse reactions:

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.

One case of medication error experienced heartburn and nausea after taking colestyramine 27 g three times a day for a week. The potential problem in overdosage would be obstruction of the gastrointestinal tract.

The location of such potential obstruction, the degree of obstruction, and the presence or absence of normal gut motility would determine treatment.

Pharmacotherapeutic group: Bile acid sequestrants, ATC code: C10AC01.

Colestyramine resin absorbs and combines with the bile acids in the intestine to form an insoluble complex which is excreted in the faeces. This results in a continuous, though partial, removal of bile acids from the enterohepatic circulation by preventing their reabsorption. The increased faecal loss of bile acids leads to an increased oxidation of cholesterol to bile acids and a decrease in serum cholesterol levels and low-density lipoprotein serum levels.

Colestyramine is hydrophilic but it is not soluble in water, nor is it hydrolysed by digestive enzymes.

In addition to the bile acids, cholestyramine can also bind other substances (e.g. certain drugs, fat-soluble vitamins) and interfere with their absorption and/or enterohepatic circulation.

In patients with partial biliary obstruction, the reduction of serum bile acid levels reduces excess bile acids deposited in the dermal tissue with resultant decrease in pruritus.

Colestyramine is not absorbed from the digestive tract.

In studies conducted in rats in which colestyramine was used as a tool to investigate the role of various intestinal factors, such as fat, bile salts and microbial flora, in the development of intestinal tumours induced by potent carcinogens, the incidence of such tumours was observed to be greater in colestyramine-treated rats than in control rats. The relevance of laboratory observation from studies in rats to the clinical use of this medicine is not known. A long-term study in humans does not reveal any significant difference between patients treated with cholestyramine and those treated with placebo with respect to the incidence of cancer.

Acacia

Citric acid anhydrous

Orange juice flavour

Polysorbate 80

Propylene glycolalginate

Sucrose

Not applicable.

3 years.

Do not store above 30° C.

Original packs containing 50 or 60 laminate sachets composed of paper, polyethylene and aluminium.

Not all pack sizes may be marketed.

No special instructions.

Any unused medicinal product or waste material should be disposed of in accordance with local requirements.