Questran is a prescription medication that contains the active ingredient cholestyramine, an anion-exchange resin used to lower cholesterol levels. It is supplied as a 4 g sachet of powder that is mixed with water or other fluids before swallowing. In Hong Kong, Questran is approved by the Pharmacy and Poisons Board of the Department of Health and is classified as a prescription-only product.
Cholestyramine works by binding bile acids in the intestine. Bile acids are normally re-absorbed in the ileum and recycled back to the liver, a process that uses cholesterol. By sequestering bile acids, Questran prevents their re-absorption, which forces the liver to convert more cholesterol into new bile acids. This reduces the amount of cholesterol circulating in the bloodstream. The binding action begins shortly after the product reaches the gut and continues as long as the resin is present. Because cholestyramine is not absorbed into the systemic circulation, its effects are limited to the gastrointestinal tract.
Questran is FDA- and EMA-approved for the following indications, which are also recognized by Hong Kong health authorities:
It is typically prescribed to adults who have been evaluated for cardiovascular risk and who need an additional cholesterol-lowering strategy.
Current peer-reviewed literature provides limited evidence for off-label uses of cholestyramine. One small series of case reports suggests that bile-acid sequestrants may help control diarrhea caused by excess bile acids after bariatric surgery, but this is not an approved indication. Any such use should be pursued only under direct supervision of a qualified clinician and after a thorough risk-benefit assessment.
Ideal candidates are adults with documented hypercholesterolemia or cholestatic pruritus who are not allergic to the resin and do not have complete biliary obstruction.
Absolute contraindications
Relative contraindications
Special populations
Because cholestyramine binds substances in the gut, it can reduce the absorption of several medications:
Patients should inform their healthcare provider of all prescription drugs, over-the-counter products, herbal supplements, and vitamins before starting Questran.
This article provides educational information about Questran and is not a substitute for professional medical advice. Treatment decisions, including use for unapproved indications, must be made under the guidance of a qualified healthcare provider. The content is intended for informational purposes and does not constitute medical recommendations. Always consult a physician before starting, stopping, or changing any medication regimen.
Yes, cholestyramine is often used in combination with statins or ezetimibe to achieve additional LDL-cholesterol reduction. However, each medication should be spaced at least four hours apart to avoid interference with absorption.
Increase daily fluid intake, add dietary fiber, and consider a mild stool softener after discussing it with your pharmacist. Persistent constipation warrants a clinical review.
Cholestyramine is classified as Category B, indicating no proven risk in animal studies and limited human data. It may be used if the expected benefit outweighs potential risks, but only under medical supervision.
A measurable reduction in LDL-cholesterol is typically observed within 2-4 weeks of consistent dosing, with maximal effect reached after several months.
Because cholestyramine binds substances in the gut, it can interfere with the absorption of certain oral contrast agents and some laboratory tests that rely on oral administration. Inform the laboratory of your medication use.
Each sachet contains a white, fine powder. The outer packaging is labeled with the brand name, strength (4 g), and a batch number.
A balanced diet low in saturated fat supports cholesterol-lowering goals. No specific dietary restrictions are required, but maintaining adequate calcium and vitamin D intake is advisable because the resin may reduce vitamin absorption.
Cholestyramine is contraindicated in complete biliary obstruction. In patients with non-obstructive gallstones, it may be used cautiously, but clinicians often prefer alternative lipid-lowering strategies.
Follow local waste-disposal guidelines. In Hong Kong, unused medicines can be returned to a pharmacy for safe disposal or placed in a sealed container before discarding with household waste, avoiding water sources.
Cholestyramine is not a controlled substance and does not contain prohibited stimulants. It should not affect standard drug-screening results, but athletes should disclose all medications to their governing bodies.
