Addiction is a strong mental and physical dependence on, most commonly, a drug or other substance. Some substances that can lead to addiction are alcohol, illegal drugs, some prescription medicines, inhalants (such as spray paint), and nicotine.
A person with an addiction usually has 3 or more of the following signs and symptoms:
Most people with addictions also have strong cravings for the drug or substance.
The tendency to have addiction problems can be passed from parents to their children (inherited). This tendency often is accompanied by mental health problems, such as depression.
WebMD Medical Reference from Healthwise