How Drug use Develops by Dr. John Anderson

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How Drug use Develops

Understanding Peer Pressure and Other Influences on Substance Abuse in Children

Adolescence is a brief period of optimism separating a period of ignorance from a period of ongoing cynicism. Philip Adams

Paper written by Dr. John Anderson, PhD. Bpharm, M Lit, MAPsS, Brain and Behaviour Clinic.

The transition from childhood to adult life is perhaps one of the most difficult periods we encounter over our life span. Throughout this period of pubertal development young people are at times treated by their elders as a child yet at the same time expected to respond to situations with the responsibility and maturity of an adult. It is during this phase of development the individual experiences the most extensive period of physical, emotional and social development. There is a shift in cognitive development from concrete thinking to a more sophisticated and complex abstract reasoning capability

The mental and physical status of the child at the onset of adolescence may predetermine or a least influence the ease with which the individual moves through this transition period. Factors such as family status (married or divorced), socio-economic status, academic ability, sporting prowess, history of physical or emotional abuse and the ability to maintain healthy peer relationships are but some of the factors that may pre-determine the ease with which young people pass through adolescence. Some teenagers have to cope with parents who are excessively permissive or authoritarian.

Some have to deal with parents and/or teachers who have unrealistically high expectations. Over the last decade there has been a general education policy to encourage young people to strive to stay at school to complete Year 12, oftentimes driven to achieve beyond the students capabilities. For many, the pressure to succeed does little more than destroy their self esteem, lower their frustration tolerance and drive them to escapism.

It is normal that during the adolescent phase of development the individual seeks to separate from the family and begin the process of individuation. In order to achieve this the adolescent must challenge the values espoused by their parents and teachers to determine for themselves the appropriateness of the norms that have been set down by society. It is often a period of egocentric experimentation to determine the me in the individual. Normal adolescent development therefore necessitates a need to take risks to shift from the security of family dependence to the development of an intrepid pathway of interdependent peer relationships.

They become protective of their privacy, preoccupied with self and at this stage the peer group takes priority. It is oftentimes difficult for parents to understand that all adolescent behaviour is purposeful. The behaviour is directed towards the development of an identity outside and independent of the family of origin. For the adolescent it is a phase during which they attempt to become comfortable with body image and sexuality and at the same time develop their own cognitive skills and moral values for social competence.

The ability to formulate appropriate peer relationships and the degree of risk behaviour engaged in to achieve autonomy is often determined by the status of the individuals self-esteem. Adolescents with a healthy self-esteem tend to engage in constructive risk taking behaviour and emerge as self reliant, responsible adults having learnt that there are consequences to the behaviour. Adolescents with healthy self-esteem tend to engage in group activities, sport and outdoor activities. It is easier for them to say no to peer pressure. On the other hand when self-esteem is low, undesirable peer pressure is hard to resist as giving in offers the possibility of belonging or escape. (Wallner, 1988)

Young people with low self-esteem tend to aggregate to similar peers and tend to engage in excessive risk taking behaviour. These young people are less capable of independently handling stressful situations, have greater difficulty in determining their identity and future goal directions. They quite often tend to become followers rather than leaders and find it more difficult to say no to peer pressure. The adolescent is often caught up with the dichotomy of being perceived by others as a unique individual but at the same time needing to be recognised as a reproducible member of the group by way of dress, interests, language and mirroring behaviours. they still strive to be revered within their own peer group.

I am often reminded of one such 16-year-old who presented with Conduct Disorder at our Clinic who during interview suggested that If I cant be good at being good then I want to be good at being bad. Although the objectives of the behaviour are clearly undesirable it highlights the need to be seen as becoming successful at something and a need to belong to a peer group who will readily encourage and demonstrate approval for the negative behaviour. A process of social contagion takes place resulting in the social values this negative peer group replacing their own tentatively formed set of moral values. To behave in a manner not acceptable to the group may lead to rejection.

The increased availability of drugs (both licit and illicit) in conjunction with a general increase in tolerance to drug using behaviour by society has created an attractive milieu for adolescents to engage in risk taking behaviour and at the same time consciously or subconsciously test societal norms. I am constantly reminded of Alice Woods poignant comments to the press in 1995 after the death of her sister Anna, from a single tablet of ecstasy, when she said Young people use drugs because they are FASHIONABLE and AVAILABLE. Many young people experiment with drugs and never use again. Others use intermittently in a regular controlled pattern and rarely suffer few adverse effects. Sadly, too many young people progress to a pattern of abuse that becomes obsessional and is usually associated with physical, academic and psychosocial deterioration.

Experimental and intermittent drug use is usually limited to specific situations, and the adolescent ingests sufficient to alter their mood but rarely enough to cause intoxication or overdose. However as indicated in the case of Anna Wood (Donaghy, 1996) sometimes an individual will respond to the drug in an idiosyncratic manner with disastrous results. The use of mood altering drugs usually begins in a social setting in response to intense peer pressure to join in the fun and inferentially belong to the peer group. The ability to say no is usually dependent on the aforementioned factors relating to self-esteem. However, even those adolescents with healthy self-esteem will experiment for the fun factor.

The fun factor as described by Howard and Zibert (1990) suggest that the use of drugs by young people is not necessarily the result of an inability to say no but rather may result from a complex mix of curiosity, boredom and wanting to feel good. For some, after a few often inept and unpleasant attempts to get high, the adolescent who persists will meet with success, likes the feeling, and repeats the experience many times in a range of social settings. (Schwartz et al, 1985). Some drugs such as ecstasy and amphetamines are more commonly introduced experimentally at Rave or Dance parties. Others such as alcohol and cannabis are often first experienced at parties in the home environment.

Excessive drug use is commonly a time-limited behaviour with a decrease in use often occurring after approximately 10 years. Drug use becomes a greater problem when associated with problem behaviours such a truancy, marked aggressiveness, communication problems within the family, runaway behaviour or sexual promiscuity (Sargent, 1987). It becomes of greater concern when it interferes with school performance or participation in other peer group activities that might lead to a sense of increased competency and social effectiveness.

Perhaps the most damaging psychological effect of continued cannabis abuse is the development of Amotivational Syndrome perceived as being the experience of losing interest and motivation to continue to participate in activities in which they were previously competent and enjoyed. There is a spiraling decline in academic performance and an equally dramatic sudden refusal to complete homework or assignments. The resultant consequence of a lack of input leads to a concrete outcome of failure to achieve and an ensuing further decline in self-esteem which in turn gives rise to an internalised justification for escaping reality by smoking more cannabis. And so the cycle continues until a dependent level of use is maintained.

Whilst there is no specific personality type predisposed to substance abuse there have been a number of psychosocial and physical factors identified as contributing risk factors in the development of substance abuse. The adolescent who feels he or she is a misfit, has difficulty with interpersonal relationships, lacks the support of his or her family and looks for acceptance into a peer group which indulges in drug abuse, is at risk. Chassin, Presson, Sherman and McGrew (1988) have suggested that risk factors can be broken into inter-personal and intra-personal risk factors.

They cite a widely replicated set of findings that characterise the typical adolescent at high risk for addictive behaviour. The interpersonal risk factors include peer and parent models for addictive behaviour; peer and parent attitudes that tolerate addictive behaviour; alienation from parents and parent disciplinary practices including lack of monitoring and ineffective discipline. Other factors such as the familys socio-economic status, whether or not a parent has a dependency problem, whether or not the family is intact are also interpersonal significant risk factors.

Intra-personal risk factors reported to contribute to substance abuse include behaviours of, rebellion and non-conformity, aggression and antisocial behaviour, extroversion, attitudinal tolerance for norm-violating behaviour, poor educational achievement and low educational aspirations. Additional intra-personal factors include low self esteem, depression, anxiety and self handicapping tendencies reflected in attempts to protect a fragile self esteem from failure experiences.

More recently an emerging literature from both Europe and the United States reveals a childhood history of Conduct Disorder and Attention Deficit Hyperactivity Disorder in young adults who develop polysubstance abuse. (Gittleman et.al, 1985; Ralph et al., 1989; Hogerman et al., 1993; Biederman et. al., 1995; Schubiner et al., 1995; Coger et al., 1997; Gunning 1997; Whitmore et. al., 1997; Wilens et.al., 197; Milberger et.al., 1997; Durst et. al., 1997; Horner et.al., 1997; Biederman et al., 1997; Riggs et al., 1998 Biederman et. al., 1998 (a),(b); Lambert et. al., 1998; Levin et. al., 1998; Milberger et. al., 1998; Horning et.al., 1998; Troisi et. al., 1998). These disorders are but two of the many factors that have been recognised to predispose adolescents to substance abuse.

Research would therefore seem to support the notion that there are three different types of ADD that may place an adolescent at risk for the development of substance abuse. The first of these is the neurobiological disorder more commonly known as Attention Deficit Hyperactivity Disorder. The second and third types of ADD are psychosocially based and might colloquially be referred to as Absent Dad Disorder and Absent Discipline Disorder. When all three types of ADD are combined in the same individual the possibility of the adolescent developing Substance Abuse Disorder is significantly enhanced.

Adolescents are likely to become exposed to four broad spectrums of drugs. The first of these could be referred to as the depressants. Drugs included in this category would include alcohol, cannabis (although for a few users it may act as a stimulant), inhalants,heroin, and certain prescription drugs. They are referred to as depressants because they slow the physiological functioning of the brain and some time after intoxication produce a mood state of depression. The second cluster of substances that adolescents may become exposed to are the stimulants. Drugs in this category include the amphetamines (speed),nicotine, cocaine and ecstasy (MDMA).

The third group are the hallucinogens which include lysergic acid diethylamide (LSD), phencyclidine (PCP or Angel dust), mescaline (peyote), and magic mushrooms which contain psilocyn and psilocybin which are chemically related to LSD. As the categorical name suggests these drugs produce hallucinatory experiences which are most frequently visual or tactile in nature. They also exacerbate anxiety and depression. Use of these drugs might stimulate rapid onset of drug induced psychosis. Less frequently some young adolescents are caught up in steroid abuse which directly effects levels of testosterone producing increased aggression, anger/hostility and usually precipitates lengthy periods of depression.

The legal drugs (alcohol and tobacco) are most often the first drugs adolescents tend to experiment with. In todays society it is seen by many that binge drinking in young adolescent males is somehow perceived as a rite of passage. Binge drinking refers to the behaviour of intentionally drinking to such excess that the individual will pass out. Cannabis is usually the first of the illicit drugs with which adolescents tend to experiment. Estimates in the 1995 National Drug Survey indicate that 41% of young people in the 14-19 age group had used cannabis in the previous 12 months and that about 10% of adolescents in this age group had used cannabis on a once a week or more basis. These estimates would suggest that on average there would be approximately two adolescents in each classroom from year 8 to year 12 were frequent users of cannabis.

Table 1
Cannabis sativa

1) 61 Different Cannabinoids

2) Delta-9-Tetrahydrocannabinol THC
  Leaf content 1-14% skunk 30%
  Hashish content 8-14%
  Hashish Oil up to 60%

3) Cannabis is LIPOPHYLIC (Fat Soluble) Poorly Excreted

4) Cannabidiol CBD

5) Cannabinol CBN

6) CBD and CBN interfere with reproductive and immune systems
  chromosome formatin
  spermatogenisis
  LH Prostoglandins Prolactin

7) Contains more carcinogens than tobacco > 50%

8) Adverse effects on Cardiovascular and Respiratory Systems

9) Behavioural Changes
  Depersonalisation
  Increased Anxiety
  Increased Depression
  Slowing of Reaction Times
  Short Term Memory
  Amotivational Syndrome
  Temporal Disorientation
  Changes in perception
  Alteration to Spatial Representation

There are many names for varieties, strengths and forms of the cannabis plant. Marijuana is the most common name but it is also frequently referred to as dope, grass or pot. Cannabis, originally native to central Asia, is a common weed and now grows extensively in many parts of the world. There are many forms and parts of the plant used, often mixed with tobacco, in a cigarette form known as a joint or through a water pipe referred to as a cone, bong or billie (see Table 1). The most common form used by young people today is a hydroponically grown hybrid sometimes referred to as skunk or madweed.

The psychoactive chemical delta-9 tetrahydrocannabinol (THC), is but one of over 60 cannabinoids found in the plant. It is the psychoactive properties of THC that creates the stone or euphoric effect when cannabis is smoked. Unlike all of the other illicit substances as well as nicotine and alcohol, cannabis and its active principles are fat soluble (lipophylic) and are therefore very slowly excreted from the body. THC has what is called a half life of eight days, which means that 50% concentration of it is still present in the body eight days after its initial use. After consumption of one joint (which is approximately equivalent to 5 cones) aberrant, subtle but significant brain dysfunction can be detected eight to twelve weeks later.

Similar brain dysfunction can be detected in long term regular users of cannabis three to five years after complete abstinence. The lipophylic properties of the cannabinoids in cannabis permits strong binding to proteins and fat cells concentrated in the brain, liver and reproductive systems. It is this property of cannabis that sustains both acute and long term effects on brain function (problems with short term memory, concentration, temporal disorientation, changes in perception and mood swings). In addition it produces serious inhibition of liver function metabolism and suppresses the immune system. Because it is slowly excreted it can also have significant effects on hormonal balance of the reproductive system. No other illicit drug has these lipophylic properties.

Marijuana contains up to 50 to 70% more carcinogens than tobacco. The tars and other active principles contained in the plant produces similar harmful effects on both the respiratory and cardiac systems as with tobacco. Natural cannabinoids such as cannabidol (CBD) and cannabinol (CBN) and cannabichromene are not psychoactive but are biologically active. They affect DNA, RNA and protein synthesis. Both CBD and CBN have been implicated in producing a carcinogenic effect in non-lymphoblastic leukemia and tongue, throat and oesophogeal cancer.

Consumption of large amounts of cannabis even for a short period can produce drug induced psychosis. The NSW Health Minister reported to parliament last year (1998) that the number of presentations to NSW psychiatric units of cannabis related drug induced psychosis had risen from 15% in 1993 to 26% in 1997. Whilst a transient drug induced psychotic experience may last from hours to months or even years there is strong evidence to indicate that even small amounts of cannabis can act as a catalyst to precipitate the onset of chronic schizophrenia in those individuals who are predisposed.

There is considerable debate as to whether or not cannabis is a gateway drug to heroin abuse. Whilst this may be of some intellectual interest it is a debate that distracts from the real issues of how we can best help people who have become dependent on cannabis. It is a debate that will never be resolved by scientific endeavour as ethics approval would never be given to allow young people to be filled up with cannabis and then wait to see if they all turn to heroin.

However what can be said from clinical experience is that very few heroin users have reached that level in the chain of polysubstance abuse without having used cannabis for quite some time. It is also of interest that we have noted at our clinic that patients who have detoxed from heroin tend to increase their use of (or return to their use of) cannabis. There is an emerging picture that rehab. heroin clients seem to be attracted to using cocaine after detox. This is a trend that will have to be monitored.

In a normal brain there are two chemical messenger neurotransmitters (dopamine and noradrenaline) that constantly interchange through an enzyme called tyrosine hydroxylase to maintain a homeostatic balance. When there is too much dopamine it converts to noradrenaline and vice versa. Both dopamine and noradrenaline belong to a group of neurotransmitters called catacholamines. Dopamine is a cortical inhibitor (brake) and in addition to regulating the speed of electrical conduction along neural pathways, it is one of the primary transmitters (in conjunction with naturally occurring opiate endorphins) responsible for achieving the feeling of reward.

Noradrenaline, on the other hand, amongst other things regulates arousal and modulates emotions of anxiety,irritability, aggression and paranoia. Ingestion of cannabis leads to an increase in dopamine activation and this is part of the process contributing to the feeling of well being when the user is stoned. The level of dopamine increases and excess is converted to noradrenaline. As the stone wears off and dopamine starts to deplete the excess noradrenaline attempts to convert back to dopamine. However the THC (being fat soluble) remains in the receptor site and blocks the conversion back to dopamine.

The brain does not allow an excess level of noradrenaline to persist and in order to deplete the noradrenaline the increased level arousal is manifested as an emotional response of increased anxiety, irritability and sometimes aggressive behaviour. The manifestation of the predictable behavioural response utilises the excess noradrenaline and provides a means of returning to homeostasis. The discomfort of anxiety or frustration is an undesirable state so the user (preferring a feeling of reward) pulls another cone which in turn starts the cycle again.

Young people who enter adolescence with a neurobiologically based disorder of Attention Deficit Hyperactivity Disorder, do so with reduced levels of dopamine and noradrenaline as a function of the disorder. Such a neurochemical disturbance is manifested in behaviours of poor impulse control, inability to focus attention, short term memory problems and are physiologically hypo-aroused. They experience rapid mood swings and often experience low self esteem as a function of their inability to achieve their potential and constantly being in trouble at school for their disruptive behaviour and inability to complete tasks required of them. Again, as a function of their disorder they often seek to engage in high risk behaviour. It would seem little wonder that such an individual with these hidden handicaps, in addition to having experience the normal adolescent developmental processes, is going to be very attracted to the cannabis dealer.

The problem for these young people is compounded by the fact that at least in the initial stages, smoking cannabis will increase their abnormally low level of both dopamine and noradrenaline and they will experience a sense of normality. The cannabis smoking ADHD adolescent will feel calmer, think clearer, will be less impulsive, less hyperactive and will not have to behave in a manner to overcome the physiological hypo-aroused state ie., the ADHD individual has self medicated. If it were not for the lipophyic properties of cannabis, his improved feeling of reward could be maintained.

However because it is lipophylic and because of its long term side effects on brain and liver, in addition to its addictive nature, it does not take too long for the benefits to disappear. Unfortunately, by this time he is most likely hooked on the pathway to polysubstance abuse in order to seek out the feeling of reward. It is therefore not surprising that Gittleman et al., (1985) report their findings of ADHD adolescents tending to start smoking cannabis on a regular basis about two years earlier than Conduct Disordered or Depressed adolescents.

There is an urgent need to indentify young children who are predisposed to a difficult adolescent phase of development and put in place early intervention programs to limit the harm of risk taking behaviour. Whilst drug education programs informing adolescents of the health risks related to substance abuse are important, such programs only go part of the way. Adolescents are resistant to any notion that something harmful will happen to themself (after all they are invincible).

There is a need to develop programs to encourage and develop in parents and students alike as well as all members of the school community to become aware of their positive assets and actively develop protective factors to minimise the risk of the adolescent turning to substance abuse. Schools need to encourage peer support groups to develop a peer milieu that does not accept their fellow students using drugs. Such a change needs to be driven by the peer group rather than being seen to be a directive from the teaching staff.

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