According to CNN, around half of injection heroin users began abusing prescription opioid drugs first. Heroin is a lot more affordable and effective than well known prescription drugs like OxyContin and Vicodin.
Once addicted it is next to impossible for an addict to quit abusing the drug on their own accord "cold turkey" so to speak. The reason for this, is the powerful Heroin withdrawal symptoms addicts go through when the drug begins leaving their system.