Substance Abuse and Substance Dependence
Symptomology and diagnostic criteria
The abuse of psychotropic substances represents a maladaptive pattern of behaviour that is
associated with recurrent failure at work, school or home.
Accompanied by physically hazardous behaviour and may lead to legal problems.
Abusers might continue consumption in spite of mounting social, interpersonal or financial
Substance abuse often evolves into substance dependence.
Substance dependence is characterized by the development of tolerance due to repetitive
exposure to psychotropic substances in shortening intervals so increasing quantities are
needed to produce the desired effects such as euphoria, calmness or relief from anxiety.
Withdrawal symptoms associated with individuals with substance dependence rather than
substance abuse problems.
These symptoms include
• Increasing blood pressure
• Heartbeat rate
• Sweat production
• Psychological disturbances > confusion, hallucinations, irritability and intense anxiety
Individuals with dependence issue may spend a lot of time trying to acquire and use the
They also continue intake in spite of potentially severe physical harm or psychological
problems caused by substance use.
Even after successful detoxification and treatment of withdrawal symptoms, the rates of
relapse are incredibly high across all psychotropic substances.
Millions of people meet the criteria for dependence in developed countries.
Alcohol and nicotine most widespread legal drugs but consumption of illegal drugs such as
cocaine and heroin is also on the rise and poses a huge problem for both medical and legal
In Europe and NA, 5%10% of men and 3%5% women have alcohol dependence.
The typical onset is insidious and manifestation of first withdrawal symptoms occurs in the
third or fourth decade of life.
Environmental Risk Factors • Impoverishment
• Parental alcohol or drug abuse
• Lack of stable attachment figure
• Widespread availability of drugs.
• Early consumption in adolescence.
Reasons for high prevalence of the disorder
• Widespread availability (especially of psychotropic substances)
• Individual differences that contribute to the vulnerability
There are genetic differences amongst populations that help to explain why there is a greater
percentage of the disease in one country but not in another.
For example, slow metabolizing of alcohol leads to an accumulation of acetaldehyde, which
in turn produces an aversive reaction accompanied by nausea and sickness. This could in part
explain the lower prevalence rates of alcoholism in some East Asian peoples because people
get readily sick after drinking small quantities of ethanol.
However, despite evolved genetic differences between human populations in enzymatic
alcohol degradation, and the presence of ethanol containing food throughout human history, it
is the availability of large quantities of ethanol and other psychotropic substances that
explains the high prevalence rates.
Classical conditioning and the linking of the experience of drinking alcohol to other stimuli.
For instance, the experience that alcohol consumption provides positive feelings in certain
circumstances may trigger craving in conditions reminiscent of the original situation.
So later, even the smell of alcohol may activate the VTA and NAc in people with alcohol
dependence, and it is reasonable to assume that sometimes simply the scent of alcoholic