Drug Interactions between colestipol and FE C Tab Plus

ADJUST DOSING INTERVAL: Concomitant use of some oral medications may reduce the bioavailability of orally administered iron, and vice versa.

Food taken in conjunction with oral iron supplements may reduce the bioavailability of the iron. However, in many patients intolerable gastrointestinal side effects occur necessitating administration with food.

MANAGEMENT: Ideally, iron products should be taken on an empty stomach (i.e., at least 1 hour before or 2 hours after meals), but if this is not possible, administer with meals and monitor the patient more closely for a subtherapeutic effect. Some studies suggest administration of iron with ascorbic acid may enhance bioavailability. In addition, administration of oral iron products and some oral medications should be separated whenever the bioavailability of either agent may be decreased. Consult the product labeling for specific separation times and monitor clinical responses as appropriate.

ADJUST DOSING INTERVAL: Bile acid sequestrants and the phosphate binder, sevelamer, can decrease the absorption of fat-soluble vitamins A, D, E, and K. By binding bile acids, these agents may interfere with normal fat digestion and absorption, thereby preventing the absorption of fat-soluble vitamins. When 8 grams of cholestyramine was administered simultaneously with a normal meal containing 250,000 units of vitamin A acetate in four healthy young adult subjects, plasma vitamin A levels were significantly reduced during a 9-hour postprandial period compared to the values obtained with the control meal. Coadministration with 4 grams of cholestyramine had no significant effect. In a crossover study involving healthy subjects, coadministration of sevelamer with calcitriol resulted in a significant reduction in bioavailability for calcitriol (calcitriol with sevelamer vs calcitriol alone: AUC 137 pg*h/mL vs 318 pg*h/mL and Cmax 40.1 pg/mL vs 49.7 pg/mL, respectively). Chronic use of bile acid sequestrants has been rarely associated with an increased bleeding tendency due to hypoprothrombinemia resulting from vitamin K deficiency. Isolated cases of Vitamin A (including one case of night blindness) and D deficiencies have also been reported with chronic cholestyramine therapy.

MANAGEMENT: When bile acid sequestrants are given for prolonged periods, some manufacturers recommend that concomitant supplementation with water-miscible or parenteral forms of fat-soluble vitamins be considered. If oral vitamin supplements are used with cholestyramine or colestipol, advise patients to take them at least 1 to 2 hours before or 4 to 6 hours after the bile acid sequestrant to minimize the potential impact on their absorption. No recommendations are available for sevelamer, but it may be advisable to follow the same precautions.

The use of bile acid sequestrants is contraindicated in patients with complete biliary obstruction where bile is not secreted into the intestine. These agents adsorb and combine with bile acids in the intestine to form an insoluble complex that is excreted in the feces, resulting in partial removal of bile acids from the enterohepatic circulation. Bile acid sequestrants are ineffective if bile does not reach the intestine.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

The use of bile acid sequestrants may produce or worsen preexisting constipation. Constipation associated with these agents may aggravate hemorrhoids. Therapy with bile acid sequestrants should be administered cautiously in patients with preexisting constipation, hemorrhoids, or symptomatic coronary artery disease. The dosage should be increased very gradually according to manufacturer guidelines to minimize the risk of fecal impaction, and patients should be encouraged to increase fluid and fiber intake. Occasional use of a stool softener may also be indicated. If constipation worsens or develops during therapy, or the desired therapeutic response is not achieved at the maximum recommended daily dosage, combination therapy or an alternative agent should be considered.

Bile acid sequestrants are chloride forms of anion exchange resins and may produce hyperchloremic acidosis with chronic use. Therapy with bile acid sequestrants should be administered cautiously in patients who may be particularly susceptible, including children or smaller patients and patients with renal impairment or volume depletion.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

The use of bile acid sequestrants may produce or worsen preexisting constipation. Constipation associated with these agents may aggravate hemorrhoids. Therapy with bile acid sequestrants should be administered cautiously in patients with preexisting constipation, hemorrhoids, or symptomatic coronary artery disease. The dosage should be increased very gradually according to manufacturer guidelines to minimize the risk of fecal impaction, and patients should be encouraged to increase fluid and fiber intake. Occasional use of a stool softener may also be indicated. If constipation worsens or develops during therapy, or the desired therapeutic response is not achieved at the maximum recommended daily dosage, combination therapy or an alternative agent should be considered.

The use of bile acid sequestrants may produce or worsen preexisting constipation. Constipation associated with these agents may aggravate hemorrhoids. Therapy with bile acid sequestrants should be administered cautiously in patients with preexisting constipation, hemorrhoids, or symptomatic coronary artery disease. The dosage should be increased very gradually according to manufacturer guidelines to minimize the risk of fecal impaction, and patients should be encouraged to increase fluid and fiber intake. Occasional use of a stool softener may also be indicated. If constipation worsens or develops during therapy, or the desired therapeutic response is not achieved at the maximum recommended daily dosage, combination therapy or an alternative agent should be considered.

Questran Light and LoCholest Light (brands of cholestyramine) contain 16.8 mg and 22.4 mg of phenylalanine, respectively, per each dose. Flavored Colestid (brand of colestipol) contains 18.2 mg of phenylalanine per each 7.5-gram dose. WELCHOL (brand name of colesevelam) for Oral Suspension contains 13.5 mg phenylalanine per 1.875 gram dose and 27 mg phenylalanine per 3.75 gram dose. The phenylalanine content should be considered when these products are used in patients who must restrict their intake of phenylalanine (i.e. phenylketonurics). Regular Colestid, Questran and LoCholest do not contain phenylalanine.

Bile acid sequestrants are chloride forms of anion exchange resins and may produce hyperchloremic acidosis with chronic use. Therapy with bile acid sequestrants should be administered cautiously in patients who may be particularly susceptible, including children or smaller patients and patients with renal impairment or volume depletion.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.

Bile acid sequestrants may interfere with the absorption of folic acid and fat soluble vitamins such as A, D, and K. Chronic use of bile acid sequestrants may cause increased bleeding tendency due to hypoprothrombinemia associated with vitamin K deficiency. Anemia may also occur due to reduced serum or red blood cell folate. Supplementation with oral vitamins and/or folate should be considered during prolonged therapy with bile acid sequestrants, particularly in patients with preexisting vitamin and/or folate deficiencies, anemia, or a bleeding diathesis.