How to Give GTN Orally

All the blood that is absorbed from the gastrointestinal tract gets taken to the liver. And so this is what we call the first pass. It has to first pass the liver. The liver can modify the drug to not allow it to get into the blood. So a good example for this drug, or an example of a drug, is GTN. You give GTN orally. But as it hits the liver, the liver knocks off a lot of it. Its first pass is very poor, which means it doesn't getting into the blood very well. Therefore, its bioavailability is very low. Yeah. Oh, this is kind of for the oral ingestion method. There's one final point