Cholestyramine
QUESTRAN
What it isBile acid sequestrant; hyperlipidemia, bile acid diarrhea, and drug washout.
Why this oneIt is not absorbed at all, so it is usable in pregnancy, and it is the agent for bile acid diarrhea and for washing out leflunomide.
What limits itIt binds other drugs in the gut — dose everything else one hour before or four hours after. Constipation and poor palatability.
FDA-approved for
- hyperlipidemia (~1973)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Primary hypercholesterolemia | Adults | 4 g (1 packet/scoopful) QD–BID | 8–16 g/day divided BID | 24 g/day |
Titration Increase dose gradually with lipid reassessment at intervals of not less than 4 weeks
Renal Undefined
Hepatic Undefined
Instructions
- Never take in dry form; always mix with 2–6 oz water or non-carbonated fluid
- Preferred timing at mealtime
- May interfere with absorption of other drugs/fat-soluble vitamins — separate dosing of other medications
- May be given in 1–6 doses per day
Contraindications
- Complete biliary obstruction (bile not secreted into intestine)
Cautions
- Chronic use may cause fat-soluble vitamin (A, D, K) deficiency; hypoprothrombinemia/bleeding
- Hyperchloremic acidosis (esp. children); constipation may aggravate hemorrhoids
- May interfere with absorption of concomitant oral drugs
Adverse reactions
- Constipation (most common; dose- and age-related)
- Abdominal discomfort/pain, flatulence, nausea, vomiting, diarrhea, steatorrhea
- Bleeding tendency from vitamin K deficiency; vitamin A/D deficiency
- Rash, skin/tongue/perianal irritation; rare intestinal obstruction in children
Pregnancy Category C; not absorbed systemically but may impair fat-soluble vitamin absorption — prenatal supplementation may be inadequate
Lactation Undefined
NO BOXED WARNINGS
Principal riskBinds other drugs in the gut; constipation
Cost, est. cash$5–$150/month
Generic entry1988
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityLocal irritation, sensitization or administration-site injury; negligible systemic toxicity at usual use.
Mechanism of action: Cholestyramine ballicule
