Drug Distribution (Lecture IV)

What are the most important physiochemical properties of a drug that affect drug distribution to a specific tissue?

• pKa

• Lipid solubility

• Molecular weight

How do insoluble drugs appear to be primarily distributed?

Associating with plasma proteins

True or False: Plasma protein binding is unreversible.

FALSE

What plasma protein do drugs primarily bind to?

Albumin

When two highly protein bound drugs are used concurrently, displacement from binding sites can result in increased _______.

free (active) drug

Acidic drugs bind to _____

Albumin

Basic drugs bind to ______ and _____

alpha-1-acid glycoproteins and lipoproteins

Above groups of lysine and carbocylic acid groups of aspartic and glutamic acid attract drugs through _______.

electrostatic forces

What are the 3 pharmacological sanctuaries?

• brain

• Operated

• Eye

What do efflux proteins do?

remove drug from protected sites

• p-glycoprotein

What are the symptoms of ivermectin toxicity?

• depression

• Lethargy

• Seizures

• Blindness

• Coma

What breeds are at the highest risk of ivermectin toxicity?

herding breeds

Volume of Distribution

volume of all tissue that dilutes the drug which determines the dose

Protein Bound drugs are limited to the ____

plasma

Water soluble drugs are in the _____ fluid

extracellular

Lipid soluble drugs are in the ____, ____, and ____ or total body water.

plasma; ECF; ICF