Dosing and uses of Prevalite, Questran (cholestyramine)
Adult dosage forms and strengths
powder for oral suspension
- 4g resin/5g powder
- 4g resin/5.5g powder
- 4g resin/5.7g powder
- 4g resin/6.4g powder
- 4g resin/9g powder
Hyperlipidemia
4 g PO q12-24hr; not to exceed 24 g/day (4 g q4hr)
Overdose: Symptoms include gastrointestinal (GI) obstruction; treatment is supportive
Dosing Modifications
Renal impairment: Supplemental doses not necessary with peritoneal dialysis (PD) or hemodialysis (HD)
Administration
Always mix with fluids or food
Take before or with meals
Pediatric dosage forms and strengths
powder for oral suspension
- 4g resin/5g powder
- 4g resin/5.5g powder
- 4g resin/5.7g powder
- 4g resin/6.4g powder
- 4g resin/9g powder
Hyperlipidemia
240 mg/kg/day PO divided q8-12hr; generally not to exceed 8 g/day
Prevalite, Questran (cholestyramine) adverse (side) effects
Frequency not defined
Belching
Constipation
Dental erosion
Diarrhea
Duodenal ulcer bleeding
Flatulence
Gallstones
Heartburn
Hypoprothrombinemia
Malabsorption of fat-soluble vitamins
Nausea and vomiting
Pancreatitis
Perianal irritation
Rectal pain
Steatorrhea
Stomach pain
Weight gain or loss
Warnings
Contraindications
Hypersensitivity to bile-sequestering resins
Complete biliary obstruction
Cautions
Use with caution in renal impairment
Volume depletion
Concomitant spironolactone therapy
Secondary causes of hyperlipidemia must be ruled out before therapy is initiated
Not to be used as monotherapy in hypertriglyceridemia
With prolonged use, increased risk of bleeding because of hypoprothrombinemia from vitamin K deficiency
May interfere with fat absorption and decrease absorption of fat-soluble vitamins (A, D, E, K)
May exacerbate preexisting constipation (initiate therapy at lower dosage in patients with history of constipation)
Special care must be taken to avoid constipation in patients with symptomatic coronary heart disease
Always mix with water or fluids; never ingest dry powder
Some formulations contain phenylalanine
Because of large quantities of chloride ion released from resin (which may lead to hyperchloremic acidosis and increase urinary calcium excretion on prolonged use), it may be advisable to reduce chloride intake
Take other drugs at least 1 hour before or 4-6 hours after taking cholestyramine to minimize possible interference with absorption
Pregnancy and lactation
Pregnancy category: C
Lactation: Drug does not enter breast milk; use with caution because of potential vitamin loss in mother
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Prevalite, Questran (cholestyramine)
Mechanism of action
Forms complex with bile acids that is not absorbed through intestine; inhibits enterohepatic reuptake of intestinal bile salts, and this, in turn, increases fecal loss of bile salt-bound LDL and consequently reduces serum cholesterol in patients with primary hypercholesterolemia
Absorption
Not absorbed
Peak effect: 21 days
Metabolism
Not metabolized
Elimination
Excretion: Feces (insoluble complex with bile acids)
