These are bile sequestering agents:
- Cholestyramine (Questran)
- Colestipol (Colestid)
Bile produced in the liver and stored in the gall bladder is released when you have a fatty meal and it goes down the biliary tree, into the small intestine and emulsifies fat. This allows the fat to go into the blood stream and while it may put some weight on a person, it can also end up in the coronary arteries and build up as plaque. The bile gets reabsorbed from the blood stream and works its way back into the liver and back into the gall bladder so it’s ready for your next meal. Every time it does this cycle, the bile carries fat with it and the fat could end up in the form of lipids and plaque. What we’re trying to do is break this cycle so the bile doesn’t keep bringing fat.
These bile sequestering drugs are taken orally and go in the GI track and bind up the bile acids. The bile cannot be reabsorbed in the blood stream and it goes out with the stool. The fat is also eliminated. Since the drug can’t get absorbed, there’s less side effects. There was a diet-drug called Alli associated with this and the side effect was anal leakage (haha). It also blocks the absorption of fat-soluble vitamins (A,D,E,K) so you can’t take these vitamins at the same time.
Most patients can’t have this product though. It comes in a packet that looks grainy and looks like sand, tastes like sand. When you mix it with apple sauce, you have apple sauce sand. The manufacturer then tried to make a tablet form and people almost choked on it. Then people tried to make a wafer out of it and people said it’s like I’m chewing sand. Most people just can’t tolerate it. The people that can tolerate it though, do great with this drug.
Recap
- Blocks enterohepatic recycling
- Binds bile acids in GI tract, causing elimination
- Interaction – Binds fat soluble medications and vitamins, therefore administer at different times
So, we just reviewed drugs that increase elimination of lipoproteins. Everything else we talk about now are about decreasing production of lipoproteins.