Anion exchange resin
Cholestyramine, is a strongly basic quaternary ammonium anion exchange resin, it is used in low-density lipoprotein hyperlipidemia that includesⅡa, Ⅱb hyperlipidemia,it is the strongest cholesterol-lowering drug . After oral administration , it is not absorbed ,in the intestine the containing chlorine ion is exchanged with the bile acid,it can bind stably with bile acids until the feces, it can reduce the absorption of exogenous cholesterol, hinder the enterohepatic circulation of bile acids absorbed into blood ,it can reduce the amount of bile acids in the blood , which prompt blood cholesterol conversion to bile acids, which lowers cholesterol. Cholestyramine has no lowering effect on triglycerides. Because of the powerful cholesterol-lowering effect, the product becomes the choice of drug for type Ⅱa hyperlipoproteinemia. It shall be used in combination with drugs which can reduce blood triglyceride such as clofibrate or nicotinic acid for the treatment of type Ⅱb hyperlipoproteinemia .For hyperlipoproteinemia Ⅲ, Ⅳ, Ⅴ , we should not use cholestyramine. In addition, the product can also be used for the treatment of skin itching caused by atherosclerosis and cirrhosis, cholelithiasis .
Indications
Cholestyramine: it is mainly used for the treatment of type Ⅱa hyperlipoproteinemia, especially in familial hypercholesterolemia.
Also it is used for the treatment of primary biliary cirrhosis, drug-induced cholestatic jaundice itching, hypercholesterolemia, chronic cholecystitis, gallstones,Porphyrin thesaurismosis .
Treatment of Atherosclerosis: 4~5g, 3 times/d. Itching: Start amount of 6~10g/d, maintenance dose of 3g/d,administration for 3 times .
Long-term use can reduce intestinal binding bile salt ,and cause fat malabsorption, long-term use should add vitamin A, D, K and other fat-soluble vitamins and calcium appropriately , gastrointestinal responders may be appropriate with stomach medication.
The above information is edited by the chemicalbook of Tian Ye.
Adverse reactions and precautions
1. Start taking can cause nausea, bloating, diarrhea, constipation and other gastrointestinal side effects, which may disappear when continuing taking . It should be discontinued, if constipation is too long, individual patients can suffer intestinal obstruction.
2. The product is dry powder, and the smell is unpleasant , so it needs to be taken by mixing thoroughly with water and flavors.
3. Long-term large doses, since it can affect the absorption of fat and fat-soluble vitamins, vitamin A, D, K and calcium should be added appropriately .
4. Long-term use of cholestyramine can cause folic acid deficiency, especially in children, so it is necessary to add folic acid daily 5mg.
5. Cholestyramine can combine with cardiac glycosides, double coumarin anticoagulant drugs, hydrochlorothiazide, phenobarbital, thyroxine, phenylbutazone, warfarin and other drugs, which hinders the absorption of these drugs, when it is taken with these drugs ,it needs a certain time interval.
Uses
Lipid-lowering drugs for type Ⅱ hyperlipidemia, atherosclerosis and other diseases.
Chemical Properties
White or almost white, fine powder, hygroscopic.
Uses
Antihyperlipidemic;
ion-exchange resin (bile salts).
Uses
Cholestyramine is used in biological study for current trends in anti-thyroid drug treatment of Graves disease. It is also used in pharmacological activity in treatment of capecitabine-induced enterocolitis.
Uses
Cholestyramine, like colestipol, binds bile acids, which are removed from the organism in
a form bound to the ion-exchange resin. They are used for the same indications.
Definition
A synthetic, strongly basic anion exchange resin that
contains functional quaternary ammonium groups
linked to a styrene-divinylbenzene copolymer.
Indications
Cholestyramine
is a powder that is mixed with water or another fluid before ingesting.
Colestipol (Colestid) is another ion exchange resin that may be substituted
in patients who find cholestyramine too constipating. Like charcoal, ion
exchange resins may bind other orally administered drugs.
brand name
Cholybar (Parke-
Davis); Duolite AP143 Resin (Rohm and Haas); Questran
(Bristol Labs); Questran Light (Bristol Labs).
General Description
Cholestyramine (Cuemid,Questran) is the chloride form of a strongly basic anionexchangeresin. It is a styrene copolymer with divinylbenzenewith quaternary ammonium functional groups. After oral ingestion,cholestyramine resin remains in the gastrointestinaltract, where it readily exchanges chloride ions for bile acids inthe small intestine, to be excreted as bile salts in the feces.Cholestyramine resin is also useful in lowering plasma lipids.The reduction in the amounts of reabsorbed bile acids resultsin increased catabolism of cholesterol in bile acids in the liver.The decreased concentration of bile acids returning to theliver lowers the feedback inhibition by bile acids of 7- -hydroxylase, the rate-limiting enzyme in the conversion ofcholesterol to bile acids, increasing the breakdown of hepaticcholesterol. Although biosynthesis of cholesterol is increased,it appears that the rate of catabolism is greater, resulting in anet decrease in plasma cholesterol levels by affecting LDLclearance. The increase of LDL receptors in the liver that occurswhen its content of cholesterol is lowered augments thisbiochemical event.
General Description
White to buff-colored fine powder. Odorless or a slight amine odor. Insoluble in water. A synthetic strongly basic anion exchange resin in which quaternary ammonium groups are attached to a styrene/divinylbenzene copolymer chain.
Air & Water Reactions
Hygroscopic [Merck.] Insoluble in water.
Reactivity Profile
An amine. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.
Hazard
Low toxicity; tumorigen; questionable carcinogen; teratogen.
Health Hazard
SYMPTOMS: Symptoms of exposure to CHOLESTYRAMINE RESIN may include nausea, abdominal discomfort indigestion and constipation. It also causes vitamin K deficiency, rash, mucous membrane irritation, osteoporosis and eosinophilia. Other symptoms include flatulence, vomiting, diarrhea, heartburn, anorexia, steatorrhea, vitamin A and D deficiencies and hyperchloremic acidosis in children.
Fire Hazard
Flash point data for CHOLESTYRAMINE RESIN are not available. CHOLESTYRAMINE RESIN is probably combustible.
Biological Activity
Cholestyramine is a cationic exchange resin polymer. This resin is a bile acid sequestrant th at interchanges chloride anions for bile acids of the small intestine lumen, leading to excretion of bile acids in the feces and reduced levels of serum bile acid. Cholestyramine is used to tre at primary hypercholesterolemia. The resin induces dose-dependent reduction of low-density lipid (LDL) cholesterol. It ameliorates the risk of coronary artery disease.
Pharmacology
Cholestyramine, an anion exchange resin,
is frequently effective, although, as mentioned earlier, its antipruritic effect
seems separate from its ability to normalize bile salt levels.
Clinical Use
Cholestyramine resin is the drug of choice for type IIa hyperlipoproteinemia.When used in conjunction with a controlleddiet, it reduces -lipoproteins. The drug is an insolublepolymer and, thus, probably one of the safest because itis not absorbed from the gastrointestinal tract to cause systemictoxic effects.
Safety Profile
Low toxicity by
ingestion. Questionable human carcinogenproducing colon tumors. An experimental
teratogen. Other experimental reproductive
effects. Toxic effects by ingestion: acidosis
and nosebleeds. When heated to
decomposition it emits acrid smoke and
irritating fumes.
Synthesis
Cholestyramine (20.1.2) is a copolymer of divinylbenzene and styrene,
which undergoes chloromethylation and afterwards is reacted with triethylamine.
Drug interactions
Potentially hazardous interactions with other drugs
Anticoagulants: effect of coumarins and phenindione
may be enhanced or reduced.
Ciclosporin: may interact unpredictably with
ciclosporin. Take ciclosporin at least 1 hour before or
4-6 hours after to prevent problems with absorption.
Leflunomide: avoid concomitant use.
Raloxifene, thyroid hormones, bile acids, valproate,
cardiac glycosides and mycophenolate mofetil:
absorption reduced.
Metabolism
Not applicable as colestyramine resin is not absorbed
from the digestive tract.
