Final answer:
A drug has addictive properties if it increases the level of dopamine in the brain, causing pleasurable experiences leading to psychological and physical dependence. The development of tolerance and whether the drug is an agonist or antagonist to neurotransmitters also contribute to addiction.
Step-by-step explanation:
For a drug to have addictive properties, it typically acts on the brain's reward system, often by increasing the level of dopamine which can create pleasurable experiences that prompt the individual to repeat the use of the substance.
These rewarding experiences can lead to psychological dependence, where the individual may feel a craving for the drug, or physical dependence, where the body shows withdrawal symptoms without the substance.
Factors contributing to addiction include the drug acting as an agonist or antagonist to neurotransmitter systems, the development of tolerance (where more of the drug is required for the same effect), and potentially the drug's legal status and accessibility.
Rehabilitation efforts often focus on psychotherapy, support groups such as AA and NA, and sometimes the use of pharmacotherapies like methadone that can help reduce cravings and withdrawal symptoms.