What is cholestyramine, and how does it work (mechanism of action)?
Cholestyramine is an oral medication that
reduces the levels of cholesterol in the blood and improves the itching
associated with liver disease. Cholesterol that is ingested or manufactured in
the body is eliminated primarily by conversion to bile acids in the liver and
excretion into the intestine with bile. The bile enters the intestine, and most
of the bile acids are reabsorbed from the intestine. These reabsorbed bile acids
are removed from the blood by the liver and excreted again into bile. Thus, bile
acids re-circulate in the body. Cholestyramine binds to bile acids in the
intestine. This prevents their absorption, and the cholestyramine/bile acid
complexes are eliminated in the stool. As a result, the body loses bile acids.
To compensate for this loss, the liver increases the conversion of cholesterol
to bile acids. The conversion of cholesterol to bile acids reduces the
cholesterol in the body, and the levels of cholesterol drop in the blood.
One of
the most troubling symptoms in patients with liver and biliary disease is
itching. The itching is believed in some cases to be the result of accumulation
of bile acids in the skin due to the inability of the liver or bile ducts to
eliminate bile acids normally. By binding bile acids in the intestines and
preventing their absorption, cholestyramine hastens the elimination of bile
acids from the body and skin, and the itching improves. Cholestyramine also
binds some drugs in the intestine, preventing their absorption and hastening
their elimination. Therefore, cholestyramine is useful in some situations in
which there has been an overdose of drugs. The FDA approved cholestyramine in
August 1973.
What brand names are available for cholestyramine?
Prevalite, Questran, Questran Light
Is cholestyramine available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for cholestyramine?
Yes
What are the uses for cholestyramine?
Cholestyramine is used for reducing cholesterol levels
in the blood, to relieve the itching of liver and biliary disease, and to treat
overdoses of digoxin
(Lanoxin), or thyroid hormone. Cholestyramine also is recommended for
the rapid elimination of leflunomide (Arava).
What are the side effects of cholestyramine?
The most common side effects of cholestyramine are:
- constipation,
- abdominal pain,
- bloating,
- vomiting,
- diarrhea,
- belching,
- gallstones,
- weight loss, and
- excessive passage of gas (flatulence).
Other side effects include:
- discolored tooth,
- gastric ulcer, and
- gastrointestinal bleeding.
Long-term
use of cholestyramine may cause a deficiency of vitamin A, D, E, and K.
Constipation can be an important side effect of cholestyramine, perhaps because
the presence of free bile acids in the intestine helps determine the amount of
water in stool, and cholestyramine binds the free bile acids. It is recommended
that additional fluids be drunk when taking cholestyramine; however, it is not
known for certain if this prevents constipation, and more aggressive treatment
with fiber, stool softeners or even laxatives such as milk of magnesia may be
necessary.
What is the dosage for cholestyramine?
The usual dose for reducing cholesterol is 4 to 8 grams once
or twice a day. The maximum dose is 24 grams per day. Powder should be mixed
with 60 to 180 ml (2 to 6 fl oz) of water, noncarbonated beverage, pulpy fruits
or soup.
Which drugs or supplements interact with cholestyramine?
Cholestyramine decreases the absorption of
warfarin (Coumadin,
Jantoven), thyroid hormones (levothyroxine
sodium [Synthroid, Levoxyl, Liotrix], digoxin (Lanoxin),
and thiazide diuretics (Hydrodiuril, Oretic, Dyazide, Maxide). Therefore, these
drugs should be administered 1 hour before or 4-6 hours after the administration
of cholestyramine. Cholestyramine decreases the conversion of leflunomide (Arava)
to its active form and reduces the absorption of vitamin A, D, E and K.
Latest Cholesterol News
- COVID Antiviral Pill Approval
- Are Diet Drinks Any Better?
- Diabetes Ups Alzheimer’s Risk
- Key Protein in TBI Patients
- Breastfeeding Helps Postpartum Depression
More Health News »
Trending on MedicineNet
- Breast Cancer Warning Signs
- CMT Disease
- Main Cause of Graves’ Disease
- RSV in Adults
- Ehlers-Danlos Syndrome
Is cholestyramine safe to take if I’m pregnant or breastfeeding?
Use of cholestyramine in
pregnant women has not been
adequately evaluated. Since cholestyramine is not absorbed into the bloodstream,
the risk of adverse effects on the fetus probably is low.
Cholestyramine decreases the intestinal absorption of
vitamins A, D, E and K by the mother. This could lead to a decrease in the
concentration of these vitamins in the
mother’s milk and potentially cause vitamin deficiency in the infant.
What else should I know about cholestyramine?
What preparations of cholestyramine are available?
Powder (Resin): 4 grams (Packet or Scoopful)
How should I keep cholestyramine stored?
Cholestyramine should be stored at room temperature, 15 C – 30 C (59 F – 86 F)