How does the volume of distribution (Vd) differ among various drugs, and what does a low Vd indicate about a drug's clearance in cases of poisoning?

The volume of distribution (Vd) varies among drugs, indicating how extensively they are distributed in the body. A low Vd suggests that a drug is primarily contained within the bloodstream, which can facilitate its clearance through procedures like haemodialysis in cases of poisoning.

The volume of distribution (Vd) is a measure of how a drug disperses throughout the body's fluid compartments. Drugs with a low Vd, such as heparin, are mostly confined to the bloodstream, making them more amenable to removal via haemodialysis in poisoning situations. In contrast, drugs with a high Vd are more widely distributed in tissues, complicating their clearance from the body.