II. Indications
- Hyperlipidemia adjunctive management (rare use)
- Cholestyramine is also used off-label (not FDA approved)
III. Contraindications
- Absolute
- Serum Triglycerides >500 mg/dl (bile acid resins increase Triglycerides)
- Bowel Obstruction
- Complete biliary obstruction
- Relative
- Triglycerides >200 to 300 mg/dl
IV. Mechanism
- Binds bile salts
- Results in insoluble complexes that are excreted in the stool
- Reflex in-vivo response
- LDL receptors are increased
- Additional bile acids are generated via Cholesterol oxidation
- Effects
- LDL Cholesterol decreased (15-30%)
- HDL Cholesterol increased (3-5%)
- Triglycerides increased (10 to 15%)
V. Medications
- Cholestyramine (Questran)
- Colestipol (Colestid)
-
Colesevelam (Welchol)
- Most expensive agent of the class
- May be preferred agent of class
- Lower adverse effect profile (see above)
- May be taken concurrently with Statin
- Lowers A1C by 0.5%
- Zieve (2007) Clin Ther 29(1):74-83 [PubMed]
VI. Drug Interactions
- Each binding resin has specific guidelines for timing other medications to reduce interactions
- Most stringent guidelines are to avoid medications 2 hours before or 4 hours after binding resin
- Take with water or orange juice before meals
- Binding resins may also interfere with other lipid lowering agents (e.g. Statins, Ezetimibe)
- Colesevelam appears to have less effect on other lipid lowering agent levels
- Binding resins interfere with fat soluble Vitamin Absorption
- Take Vitamins 2 hours before or 4 hours after Resin
- Colesevelam does not appear to significantly affect Vitamin Absorption
VII. Efficacy
- Lowers cardiovascular mortality by 30%
- Reduces Myocardial Infarction risk
VIII. Adverse Effects
- Gastrointestinal (GI)
- Methods to reduce adverse GI side effects
- Use moderate doses: 8-10 g per day
- Increase Dietary Fiber or supplement with Psyllium
- Colesevelam may have less GI intolerance
IX. Safety
- Bile acid resins are not absorbed, but may affect Vitamin Absorption in pregnancy
- Pregnancy Category C (for Cholestyramine) and Category B for Colestipol and Colesevelam
- Considered Safe in Lactation (not found in Breast Milk)
X. References
- (2022) Non-StatinLipid Lowering Agents, Presc Lett, Resource #380202
- (2022) Med Lett Drugs Ther 64(1659): 145-52
- (2000) Med Lett Drugs Ther 42:102-4 [PubMed]