Alcoholism: Can your genes drive you to drink? – Crime Times Vol. 3, no. 1, 1997, pages 1 & 3 & 7 –

Carvey P.M - Drugs Action in the Central Nervous System. Oxford University Press -1998

Jaffe, J.H. – Substance related disorder. In: Kaplan and Saddock’s Comprehensive Textbook of Psychiatry/VI CDROM, 1996, Williams & Wilkins – Baltimore

The National Institute of Drug Abuse (NIDA) definition of drug addiction as "a chronic relapsing disease of the brain, which is expressed in behavioral ways and occur in a social context", expresses the difficulties one meets when trying to treat this condition. The treatment of addict patients comprises pharmacologic agents and psychotherapeutic procedures aimed at helping them to reshape their behaviors.

For the sake of brevity we shall not discuss in this paper the clinical manifestations induced by each drug or drug-group. We shall only present here the general classification used by the DSM-IV for the disturbances related to substances.

According to the present edition of DSM (Diagnostic and Statistic Manual), disturbances related to substances can be divided in two groups:

1. Substance use disorders
1.a Substance dependence
1.b Substance abuse

The active principle of marijuana and hashish, D 9 cannabinol (THC), seems to be accountable for the drugs' central affects. Both forms are prepared from the leaves of a plant, Cannabis sativa.

THC is lipophilic, quickly dissolving through plasmatic membranes and having a heterogenous distribution in the brain.

Hallucinogenic or "psychedelic" drugs have the capacity to induce hallucinations without delusion.

LSD (lysergic acid diethylamide) became the hallucinogenic drug prototype due to its widespread use, as well as, because it represents a similar family of drugs, and because it was amply studied.

The LSD group includes, besides LSD (a lysergic acid derivative), mescaline (phenyl-alkyl-amine), psilocybin (indol-alkyl-amine), as well as related compounds.

The psychostimulants is a group of drugs with differing structures and common actions such as increased motor activity and lessening of sleep necessity. These drugs decrease fatigue, induce euphoria and have sympathomimetic effects (they increase sympathetic nervous system actions). The psychostimulants includes drugs of the amphetamine group and cocaine.

Alcohol is a multiple-action depressor of the Central Nervous System, and the depression caused by it is dose-dependent. Although alcohol is mainly used because of its stimulating action, this action is only apparent and happens only with moderate doses. It results from the depression of inhibitory controlling mechanisms. Under the effect of alcohol the cortex is freed from its integrative role, thus resulting confuse and disorganized thinking, as well as disruption of adequate motor control.

Certain characteristics seem to be common to all abuse-inducing drugs:

The craving is similar to all those that produce dependence, although different drug groups show different physiological and behavioral effects

Environmental factors influence not only the acute effect of the drug but, also the probability of an eventual dependence, as well as relapsing in it.

There is a genetic predisposition to dependence.

Investigations show that some alcoholics begin to drink due to social pressures or in response to stressing situations in their lives. Since the drinking behavior is initiated, its fixation is conditioned by the alcohol-induced psychophysiological reward. Contrariwise other alcoholics seem to be driven to use and abuse alcoholic beverages by an internal compulsion.

Whenever a person uses a drug and the effect it produces is somehow pleasant, this effect gets a rewarding quality for that person. As experimental research by behavioral psychologists has demonstrated, all behaviors that are reinforced by a reward have a tendency to be repeated and learned. Successive repetitions, besides fixing the reward-producing behaviors, also fix all previously indifferent stimuli, sensations, and situations, eventually associated with those behaviors.

Along mankind’s history, several pharmacological agents have been used to induce intoxication, They comprise plant extracts, fermentation products and, more recently, different synthetic substances.

In his book "Phantastica: Narcotic and Stimulating Drugs"(1924), Louis Lewin classified the distinct psychological effects of the different agents. According to him, the agents then known, could be classified as:

But why are the intoxicants (modifiers of nervous function) so sought after? What are the reasons that drive people to use them?

We think that we could assign these reasons to four basic groups:

1. In order to reduce unpleasant anxiety and depression feelings. These feelings are:

Ancient literary and religious texts show that, at all times and places, human beings deliberately used (and abused of) substances fitted to modify the nervous system functions, inducing altered bodily sensations and psychological states.