Colestyramine

1 medicine

Colestyramine is a bile-acid binder used to lower cholesterol and relieve itching from bile flow problems. Take other medicines and fat-soluble vitamins at least 1 hour before or 4 to 6 hours after it, or it will block their absorption.

Questran

Colestyramine

4g

Questran is a cholesterol medication containing Colestyramine, available as 4g sachets.

from $8.69 / sachet View

Key facts

  • Colestyramine is a bile-acid binder. It is a powder mixed with water or juice and taken before meals; it is not absorbed into the bloodstream itself.
  • Take any other medicines at least 1 hour before, or 4 to 6 hours after, colestyramine. Taken too close together, colestyramine binds to them in the gut and blocks their absorption.
  • It also reduces absorption of the fat-soluble vitamins A, D, E, and K, so long-term use may need vitamin supplementation on the same separated schedule.
  • Seek urgent care for severe or persistent constipation, severe abdominal pain, or black or tarry stools.

What colestyramine treats

Colestyramine lowers high cholesterol, particularly LDL cholesterol, by increasing the removal of cholesterol-derived bile acids from the body. It also relieves itching (pruritus) caused by bile acids building up in the skin when bile flow is partly blocked, such as in some liver and gallbladder conditions. In some settings it is used to bind and remove certain toxins or excess bile acids from the gut.

How colestyramine works

Bile acids, made from cholesterol, are normally released into the gut to help digest fat and are then reabsorbed and recycled. Colestyramine binds to bile acids in the intestine, and the resulting complex is excreted rather than reabsorbed. The liver responds by pulling more cholesterol from the blood to make new bile acids, which lowers blood cholesterol levels.

Before you take it

  • Do not take colestyramine if you have complete bile duct blockage, since bile acids cannot reach the gut for it to bind.
  • Tell your prescriber about all other medicines and supplements you take, including thyroid hormone, blood thinners such as warfarin, and other cholesterol medicines, so timing can be planned around colestyramine.
  • Mix the powder fully in water, juice, or a similar liquid before drinking; do not take the dry powder.
  • Increase fluid and fibre intake where possible, since constipation is common and can be significant.

Side effects

Common effects include constipation, bloating, gas, indigestion, and nausea.

Stop and seek urgent medical care for any of these:

  • Severe or persistent constipation, or inability to pass stool.
  • Severe abdominal pain or distension.
  • Black, tarry, or bloody stools.
  • Unusual bruising or bleeding, which may signal reduced vitamin K absorption.

Safety essentials

  • Separate colestyramine from all other oral medicines and from fat-soluble vitamin supplements by at least 1 hour before or 4 to 6 hours after. This is the single most important rule for using it safely and effectively, since missing this window can cause treatment failure of the other medicine.
  • Long-term use can lower vitamin A, D, E, and K levels; your prescriber may check levels or recommend supplements, taken on the same separated schedule.
  • Report new or worsening constipation early, since severe cases can lead to bowel obstruction.
  • Take colestyramine consistently before meals as directed, since irregular dosing reduces its cholesterol-lowering effect.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.