Pharmacokinetics
Intravenous (IV) delivers the drug directly into the blood stream, taking on its full affect. There is 100% absorption, which means all of the drug enters the circulation system. This method takes around 2 minutes to start taking effect. However, there is a downside; initial local concentration is high when injected quickly, meaning there is a lot of drug in one place. To avoid this, some drugs need to be injected slowly (e.g. chemotherapy).