Final answer:
Signs of suspected substance abuse include withdrawal symptoms opposite to the drug's effects, like arousal and agitation in those addicted to sedatives, as well as increased tolerance and psychological cravings. Methadone is prescribed to heroin addicts as a substitute to control withdrawal symptoms and reduce relapse risk.
Step-by-step explanation:
The observations and symptoms one might look for in cases of suspected substance abuse include a variety of withdrawal symptoms such as pain, tremors, seizures, and agitation, which can emerge when use is discontinued. These symptoms are typically opposite to the effects the drug has when it is consumed. For example, someone dependent on sedative drugs may experience arousal and agitation upon withdrawal. Tolerance, another key indicator of substance abuse, is when increased amounts of the substance are required to achieve the same effects. Furthermore, the DSM-5 includes psychological dependence, or drug craving, as part of the diagnostic criteria since this craving can occur even when physical dependence has not developed. In the therapeutic context, a person with heroin addiction might be prescribed methadone, a psychoactive drug, to manage withdrawal symptoms and to act as a long-term substitute for heroin. Methadone can reduce the risk of relapse because it satisfies the body's cravings for the drug, without causing the same high, thus allowing the individual to gradually disengage from substance abuse.