Cholestyramine and colestipol are bile acid sequestrants used to lower LDL cholesterol in conjunction with diet and other lipid-lowering agents. They function by binding bile salts in the intestine and promoting increased cholesterol conversion to bile acids, thereby reducing LDL levels. Common adverse effects include gastrointestinal issues and potential drug interactions, necessitating careful timing when administering other medications.

1. CHOLESTYRAMINE AND COLESTIPOL

2. CONTENTS OF THE PRESENTATION INCLUDE :-
• Introduction
• Structure
• Mechanism of actions
• Adverse effects, Drug interactions, Contraindications
• Marketed preparation examples

3. CHOLESTYRAMINE AND COLESTIPOL
• INTRODUCTION :-
• Cholestyramine and colestipol are two established bile acid sequestrants.(Bile acid
sequestering agents are hypolipidemic agents used to lower LDL cholesterol.)
• They are used in combination with diet modification or other lipid lowering
agents like niacin to treat type IIA and type IIB hyperlipidemias.
• They are formulated in powdered form (oral administration) which should be
mixed with water and taken as slurry.
• They are insoluble in water and have large molecular weight. They are neither
absorbed nor metabolized, they are totally excreted in feces.

4. COLESTIPOL STRUCTURE :- CHOLESTYRAMINE STRUCTURE :-
IUPAC name : N'-[2-[2-(2-aminoethylamino)ethyl
amino]ethyl]ethane-1,2-diamine;2-(chloromethyl)oxirane
IUPAC name : [4-[3-(4-ethylphenyl)butyl]phenyl]-
trimethylazanium

5. MECHANISM OF ACTION :-
• Cholestyramine and colestipol are anion binding resin.
• They have strong affinity for negatively charged bile salts and bile acids in
intestine and hence bind with bile salts and acids.
• The bile acid-resin complex formed is excreted into feces resulting in decrease in
bile acid concentration.
• To maintain the supply of bile acid, the metabolism of endogenous cholesterol to
bile acid is increased in hepatocytes.
• Consequently, intracellular concentration of cholesterol decreases. This result in
increased LDL receptor on liver cells and increased removal of cholesterol
containing LDL particles from circulation. Hence, the ultimate effect is lowering of
LDL-C.

6. * Colesevelam is a newer bile acid sequestrant.

7. ADVERSE EFFECTS :-
- They can cause GI related side effects like nausea, vomiting, constipation and flatulence.
-When used in large doses, they interfere with absorption of fat and fat-soluble vitamins and can
cause steatorrhea.
DRUG INTERACTIONS :-
-They may interfere with absorption of many other drugs like warfarin, thyroid
hormone, tetracyclines, fat soluble vitamins, folic acid and digoxin.
-So other drugs are taken 1-2 hour before or 4-6 hour after taking these agents.
CONTRAINDICATIONS :-
-They may increase triglyceride level, so they are contraindicated in patients with
hypertriglyceridemia.

8. MARKETED PREPARATIONS OF CHOLESTYRAMINE AND COLESTIPOL :-

9. REFERENCE :-
LIPPINCOTT ILLUSTRATED REVIEWS PHARMACOLOGY, 6TH EDITION
GOODMAN AND GILLMAN MANUAL OF PHARMACOLOGY AND THERAPEUTICS.

10. THANK YOU