ABSTRACT
Introducing Pharmacology is mostly devoted to explaining the effect drugs have on the body; in other words, their pharmacodynamic activity. This chapter explains the effect the body has on drugs, following their journey through the body – how they are absorbed, distributed, metabolised and finally eliminated. These factors are important because they all have an effect on the concentration of a drug in the body and that is key to ensuring its efficacy and also to ensuring that the potential for unwanted side-effects are minimised. This chapter will help you understand how factors such as disease and age can affect metabolism and elimination. It explores the different ways that drugs may cause side-effects and how some drugs may interact with other drugs (and some foods). The factors that determine the correct dosage of drugs are discussed and finally we consider the effects that age, pregnancy and ethnicity can have on drug metabolism.
