ABSTRACT
There are an enormous number of drugs available, both with and without a prescription. To be able to understand how drugs work, therefore, is crucial. Contribution to treatment decisions can only be achieved if the individual health professional understands how drugs work and exert their effects on the body and also what affects the body exerts on the drugs. This chapter looks at the science of pharmacology, which encompasses pharmacodynamics and pharmacokinetics. It also looks at the considerations that need to be made around polypharmacy and drug interactions. It will also look at the process of how drugs are licensed to allow appreciation of this process and know where the information supplied in the BNF about each drug comes from.
