Pharmacology is the branch of medicine and biology that seeks to understand drugs and how they affect the body. It involves the analysis of how drugs interact with the biological function of the body and how these drugs react with each other, their natures, and their properties. All drugs are considered chemicals and when ingested into the body an affect from the drug takes place. According to Doweiko (1999), “A drug is essentially a foreign chemical that is introduced into the individual’s body to bring about a specific desired response. There are many forms of drugs and how these drugs are administered in the body determines the kind of result that will take place. The Central Nervous System, (CNS) plays a major role in how these drugs will affect the body because the chemicals carry out their main effect when latched on to the receptor sites. The way in which the drug is administered or absorbed will determine how quickly or slowly the drug will begin to work and this process varies depending on the drug (Doweiko, 2009). Drugs that hit the lungs quickly will begin to work faster but will also tapper off relatively fast. Drugs that are taken orally such as tablets, pills, and liquid medications will take longer to affect the body and drugs that enter the blood stream will work much faster than those taken orally. Drugs taken orally on an empty stomach also take affect faster (Doweiko, 2009).
Most drugs Distribution then occurs which involves how the chemical moves once it enters the body. This involves both accumulation and drug transport within the body and distribution is affected based on the individual’s age, sex, muscle/adipose tissue ratio, state of hydration, genetic heritage, and health (Doweiko, 2009). Once the drug molecules are distributed they reach circulation and can be carried to the site of action. However, the drug molecule acts as a foreign substance to the body so the way the molecule transports varies depending on how the body