Читать книгу The End of addiction - Dr Volker Hitzeroth - Страница 6

Drug users, their family members and the public at large are generally not well informed about the different types of drugs of abuse. They have difficulty finding their way through the “drug maze”. Most people have based their opinion on emotional and sensational snippets of information that only cause anxiety, and are probably more related to urban legend than scientific evidence. Such snippets of information usually highlight the dangers of drugs, their addiction potential and specific problem behaviours, actions and interactions resulting from drug use. A coherent understanding of the various drugs of abuse and how they work is often lacking.

It is important that anyone who is involved with people addicted to alcohol and drugs in a personal capacity, fami-ly relationship or professional therapeutic setting should understand drugs, their differences and their effects. Getting an overview and becoming informed is critical. If you, a friend or a family member suffered from a physical illness like diabetes, high blood pressure, cancer or epilepsy, you would learn as much as you could about the condition. The same is true for drugs and alcohol-related problems. The initial step to becoming more informed about drugs and alcohol is simply to understand an overview of the drug and alcohol world. Once the bigger picture is understood, it is easier to find your way around the problem. Most people are then ready and able to face the next step.

I am sharing my thoughts on the classification of drugs and alcohol in a way that attempts to cover most drugs of abuse and is easy to understand. Please remember, however, that this is only the starting point in the process of understanding drug use and treatment.

The large number of drugs with their various chemical compositions, different mechanisms of action and numerous clinical effects has led to much confusion. Attempts to classify drugs of abuse are fraught with difficulty.

One simple method to classify drugs would be to group them according to whether or not the substance is legal. Some substances are legal with unrestricted access (for example, caffeine), while others are legal, but have certain restrictions on their availability (alcohol and nicotine, for instance, although legal are not available to those under the age of 18, while certain medications are only available on prescription from a healthcare professional). Finally, many other substances are clearly illegal (for example, cocaine, heroin and amphetamines).

Such a classification system may provide superficial clarity. It is, however, not necessarily always accurate. For instance, the legal boundaries differ from country to country. An example of this is cannabis, which is legally sanctioned in some countries but illegal in others. The same applies to alcohol, which is generally freely for sale to adults in Western countries, but restricted in most Middle Eastern states. Codeine and other medications are readily available at pharmacies in many countries, yet could get you arrested in others because they are highly scheduled and controlled drugs.

A second method of classifying drugs of abuse is to use the chemical composition of the substance as the primary determinant in the classification system. This is a useful classification system for pharmacologists, but tends to be impractical and cumbersome for everyone else. Chemical theories and chemical names are difficult to understand and complex to use in practice for those without a background in chemistry. Does it really matter that ecstasy is classified as 3.4-methylenedioxy-N-methamphetamine (MDMA)? We are probably also not interested to know that it is related to 1-(3.4-methylene-dioxyphenyl)-2-aminopropane (MDA). Both of these drugs are in a very different chemical category to heroin (an opioid agonist) and delta-9-tetrahydrocannabinol (cannabis). Such chemical names and classifications are clearly too confusing for those who do not work with these substances in a laboratory setting.

A third method of classifying drugs could be according to their ingestion route, namely oral, injected, snorted/sniffed nasally, or smoked/inhaled. This, too, is an unsatisfactory classification system. Alcohol is mostly consumed orally by drinking, while other drugs can be ingested by various routes. Although heroin is injected or smoked/inhaled, this is not in the same way that cigarettes are smoked, but rather by inhaling the fumes when heroin is heated in a particular way. This is called “chasing the dragon”, due to the curling of the smoke resembling a dragon’s tail. Cocaine and amphetamines can be injected, smoked and snorted. Various prescription medications are taken orally in tablet or capsule form, but are also often crushed and either snorted or injected.

After years of studying medicine, specialising in psychiatry and subsequently working within the substance use field, I have developed a classification system that I find practical and easy to understand. I use this system to teach substance users, their families and medical students about drugs of abuse. The classification system is related to the terms used by drug users themselves. These terms are “uppers”, “downers” and “psychedelics”. These three categories lend themselves to a simple approach to the classification of drugs. All drugs of abuse can now be classified into five large groups, namely:

1 Uppers, also generally known as stimulants.

2 Downers, also generally known as depressants, sedatives or hypnotics.

3 Psychedelics, often referred to as hallucinogens or psychomimetics.

4 Other drugs of abuse that don’t fit neatly into any of the above three categories.

5 Drugs that overlap categories.

Over the years I have encountered other texts that use a similar classification system. This system is therefore a hybrid of my own ideas, as well as the broadly accepted categories of various drugs of abuse. Some academics may argue that many drugs of abuse should be in a different category. Their reasons are varied, but are mostly based on the chemical composition or clinical effects of a substance. They are not necessarily wrong. Such different opinions simply illustrate the difficulty in trying to explain a complex situation in a simple manner. It is for this reason that I have added the fifth category for drugs which could overlap the first three categories. This fifth group of drugs could be included in more than one category due to their different chemical composition or different clinical effects.

Uppers or stimulants

Most central nervous system stimulants influence a brain chemical called dopamine.

Classic stimulants

The classic stimulants include amphetamine and cocaine. Common names for amphetamines include methamphetamine, crystalmethamphetamine, crystal meth, speed, tik or ice. Common names used to refer to cocaine include coke, crack, candy, rock, snow and flake. The smokable forms of amphetamine (tik, ice) and cocaine (crack) are highly concentrated and refined and hence also highly addictive.

Other stimulants

Other stimulants include cathinone (khat, cat), ecstasy (XTC, E, Adam, X, MDMA), PMA (doctor death), caffeine (coffee), nicotine (cigarettes, tobacco) and certain medications that are only available at pharmacies with a prescription from a doctor. Such medications include ephedrine and pseudoephedrine containing products and methylphenidate (Ritalin). Over-the-counter medications include certain anti-obesity, and cold and flu products.

Downers or depressants

Most central nervous system depressants affect a chemical in the brain called GABA or the opioid system.

Classic depressants

Classic central nervous system depressants include alcohol (ethanol), opiates (heroin) and opioids (synthetic prescription medications). Common names for heroin include smack, brown sugar, Thai white, China white, horse or H. Other classic central nervous system depressants include sedatives and hypnotic medication, such as the benzodiazepine group and an older group of medication called barbiturates.

Other depressants

Other depressant substances include GHB (gamma hydroxybutyrate or liquid ecstacy); Zopiclone and Zolpidem, which are commonly prescribed sleeping medications; and Methaqualone (mandrax, star, flowers, boggel, Mandies, ludes, Q, vitamin Q, Quaalude). Other medications in this group include meprobamate and chloral hydrate.

Opiates and opioids

Opiates and opioids are terms derived from the word opium, which refers to the poppy plant, also known as Papaver somniferum. Opiates are substances that are either derived or synthesised from the natural opium compound or its various chemical components. Examples include heroin, morphine and codeine. Routine drug screening tests usually detect opiates.

Opioids include all substances that bind on one or more of the opioid receptors in the brain. They resemble opiates, but are not necessarily directly or indirectly derived from the natural poppy plant. They are thus synthetic substances with opiate-like properties. Examples include pethidine and methadone. Routine urine drug screening tests usually require a specific request to detect opioids. Opioids therefore encompass the opiates. These two terms are, however, often used interchangeably.

Hallucinogens or psychedelics

Most hallucinogens affect a brain chemical called serotonin. They can also affect the cholinergic and the cannabinoid brain systems.

Classic hallucinogens

The classic hallucinogens are LSD (lysergic acid diethylamide, candy, blotter, microdots or acid), MDA (Eve, love drug), mescaline (peyote cactus) and psilocybin (magic mushrooms, shrooms).

Other hallucinogens

Other chemical substances that could be classified under the hallucinogens include PCP (phencyclidine, angel dust), ketamine (Special K, K or kitcat) and cannabis (weed, dagga, dope, hashish, grass, Durban poison, Malawi cob, skunk or marijuana).

Other drugs of abuse

These drugs do not fit neatly into any of the above three categories.

Anabolic steroids

They are used to increase performance and muscle mass of athletes and body builders. They are often referred to as juice or roids.

Inhalants

These substances are found in glues, nail polish removers, deodorants, air fresheners, paints, lighter fluid, paint strippers, hair spray and cleaning agents. There are five chemical classes within this group. They are aliphatic hydrocarbons (including petrol, benzine and turpentine), simple asphyxiants (butane and propane), aromatic hydrocarbons (toluene, benzene, xylene), chlorinated hydrocarbons (dichloroethylene, trichloroethane, chloroform) and nitrous oxide (laughing gas).

Volatile nitrites

They are commonly known as poppers and include amyl, butyl and isobutyl nitrite.

Some drugs are not easy to classify. They tend to cross the artificial classification boundaries and could be grouped in a number of different categories. These substances are therefore placed in a fifth group.

Drugs that overlap categories

Ecstasy, MDA and mescaline

These can be classified as stimulants or a hallucinogens. They have an effect on both dopamine and serotonin.

Cannabis and PCP

These are classified as hallucinogens in my classification system, but also have stimulant and depressant effects.

Inhalants

These may also have depressant effects.

Please note that in the above categories I have dealt with each drug individually. However, most people who abuse drugs or alcohol do not use them in isolation. They often use more than one drug at a time. Stimulants may be used to get a high, after which depressants might be used to come down again. Numerous depressants are used in combination, for example alcohol and benzodiazepine medication are used together to enhance their effects – with potentially life-threatening consequences. Hallucinogens may cause a “bad trip” with resultant use of depressants to recover. Other common combinations include alcohol used with cocaine, cocaine with cannabis or cocaine with heroin. Such combinations change often, depending on the local drug culture.

Various adulterants or mixer substances may also be added to a drug in order to add volume. Such adulterants are varied and can include sugar, various medications, other drugs, quinine and strychnine. Even washing powder and Rattex poison have been used for this purpose. Polydrug abuse, especially when these substances have been adulterated, adds to the unpredictability, complexity and dangers associated with drug use.

Some drugs that have received attention in the media in recent years include the so-called “date-rape” drugs. This term refers to two drugs in particular, namely a benzodiazepine with the chemical name of flunitrazepam (brand name of Rohypnol and commonly known as roofies or rope) and GHB. Both of these substances cause an anterograde memory problem which means that one is unable to recall events while under the influence of these substances. Common “party” drugs used during raves or in nightclubs include stimulants such as ecstasy and methamphetamine, hallucinogens such as LSD and ketamine, and depressants such as various benzodiazepines and GHB.

It should be remembered that any classification system would have to change over time in order to accommodate newly discovered drugs from our natural plant and animal world. Similarly, new synthetically designed and manufactured drugs complicate any classification system even further.

HOW DANGEROUS IS DAGGA?

Dagga is the South African name for cannabis, which is made from the plant Cannabis sativa. Its active ingredient is 9 tetra-hydro-cannabinol (9THC). Other names for cannabis include grass, weed, dope, pot, hemp and marijuana, among many others. When cannabis is rolled into a cigarette, it is called a joint; when it is wrapped in newspaper, it is called a zol. Cannabis mixed with mandrax (methaqualone) is commonly known as a white pipe. A particularly potent form of cannabis is hash or hashish. Usually, cannabis is smoked and thus reaches the lungs and blood very rapidly, from where it enters the brain. Occasionally, dagga is consumed in the form of dagga cookies.

Many myths exist about dagga and its effect on the body. The majority of these assert that dagga is either completely harmless or extremely dangerous. Neither is likely to be true, with the truth probably lying somewhere in the middle. It is difficult to give absolute medical facts on this question, as the evidence in most studies on the effect of dagga on the human body remains inconclusive.

We know that dagga and its purported medicinal properties have been known for many centuries. These include effects on inflammation, pain, seizures, nausea and anorexia. Dagga has therefore been used as an anti-inflammatory, analgesic, anti-convulsant, anti-emetic and appetite enhancer. Yet, numerous studies seem to implicate dagga in a number of adverse health consequences. These include respiratory inflammation, infections, cancers, cardiac effects, as well as adverse effects on human sexual functioning with a reduction in the sex hormones, sperm production and ovulation.

Dagga also seems to have adverse mental health consequences, particularly with early onset and regular dagga consumption. Specifically, dagga seems to be associated with an increased risk of depression. Exposure to dagga in vulnerable individuals may also lead to the development of psychosis. This may be especially relevant in the young and developing brain, for example, in teenagers and younger adults. Cannabis also seems to play a causal role in the development of schizophrenia. Once again, this risk seems to be increased in vulnerable individuals.

Short-term memory problems and possibly even irreversible cognitive problems have also been identified in early onset and frequent dagga users. Lastly, a particular psychiatric syndrome called amotivational syndrome has been identified. This is a clinical condition in which chronic and frequent dagga users seem to develop apathy, listlessness, fatigue and tiredness, as well as anhedonia with associated decreased motivation, drive, self-care and a lack of personal hygiene, work functioning and subsequent reduction in potential.

Finally, dagga has often been implicated as a “gateway” drug, leading to other potentially more dangerous drugs. It is therefore supposedly the first step on the path to more problematic drug use. The evidence suggests that this may be true in some instances, but the decision to proceed to other drugs is usually far more complex than a simple slide from dagga to the next illegal drug.