The dependence that most concerns modern society is one in which individuals become dependent on or addicted to certain substances such as alcohol, drugs, tobacco (nicotine), caffeine and solvents. This is often called substance abuse. Some people become addicted to certain foods or activities: examples of the latter include gambling, computer games and use of the Internet.
The 28th report of the World Health Organisation Expert Committee on Drug Dependence in 1993 de?ned drug dependence as: ‘A cluster of physiological, behavioural and cognitive phenomena of variable intensity, in which the use of a psychoactive drug (or drugs) takes on a high priority. The necessary descriptive characteristics are preoccupation with a desire to obtain and take the drug and persistent drug-seeking behaviour. Psychological dependence occurs when the substance abuser craves the drug’s desirable effects. Physical dependence occurs when the user has to continue taking the drug to avoid distressing withdrawal or abstinence symptoms. Thus, determinants and the problematic consequences of drug dependence may be biological, psychological or social and usually interact.’
Di?erent drugs cause di?erent rates of dependence: TOBACCO is the most common substance of addiction; HEROIN and COCAINE cause high rates of addiction; whereas ALCOHOL is much lower, and CANNABIS lower again. Smoking in the western world reached a peak after World War II with almost 80 per cent of the male population smoking. The reports on the link between smoking and cancer in the early 1960s resulted in a decline that has continued so that only around a quarter of the adult populations of the UK and USA smokes. Globally, tobacco consumption continues to grow, particularly in the developing world with multinational tobacco companies marketing their products aggressively.
Accurate ?gures for illegal drug-taking are hard to obtain, but probably approximately 4 per cent of the population is dependent on alcohol and 2 per cent on other drugs, both legal and illegal, at any one time in western countries.
How does dependence occur? More than 40 distinct theories or models of drug misuse have been put forward. One is that the individual consumes drugs to cope with personal problems or diffculties in relations with others. The other main model emphasises environmental in?uences such as drug availability, environmental pressures to consume drugs, and sociocultural in?uences such as peer pressure.
By contrast to these models of why people misuse drugs, models of compulsive drug use – where individuals have a compulsive addiction
– have been amenable to testing in the laboratory. Studies at cellular and nerve-receptor levels are attempting to identify mechanisms of tolerance and dependence for several substances. Classical behaviour theory is a key model for understanding drug dependence. This and current laboratory studies are being used to explain the reinforcing nature of dependent substances and are helping to provide an explanatory framework for dependence. Drug consumption is a learned form of behaviour. Numerous investigators have used conditioning theories to study why people misuse drugs. Laboratory studies are now locating the ‘reward pathways’ in the brain for opiates and stimulants where positive reinforcing mechanisms involve particular sectors of the brain. There is a consensus among experts in addiction that addictive behaviour is amenable to e?ective treatment, and that the extent to which an addict complies with treatment makes it possible to predict a positive outcome. But there is a long way to go before the mechanisms of drug addiction are properly understood or ways of treating it generally agreed.
Effects of drugs Cannabis, derived from the plant Cannabis sativa, is a widely used recreational drug. Its two main forms are marijuana, which comes from the dried leaves, and hashish which comes from the resin. Cannabis may be used in food and drink but is usually smoked in cigarettes to induce relaxation and a feeling of well-being. Heavy use can cause apathy and vagueness and may even cause psychosis. Whether or not cannabis leads people to using harder drugs is arguable, and a national debate is underway on whether its use should be legalised for medicinal use. Cannabis may alleviate the symptoms of some disorders – for example, MULTIPLE SCLEROSIS (MS) – and there are calls to allow the substance to be classi?ed as a prescribable drug.
About one in ten of Britain’s teenagers misuses volatile substances such as toluene at some time, but only about one in 40 does so regularly. These substances are given o? by certain glues, solvents, varnishes, and liquid fuels, all of which can be bought cheaply in shops, although their sale to children under 16 is illegal. They are often inhaled from plastic bags held over the nose and mouth. Central-nervous-system excitation, with euphoria and disinhibition, is followed by depression and lethargy. Unpleasant effects include facial rash, nausea and vomiting, tremor, dizziness, and clumsiness. Death from COMA and acute cardiac toxicity is a serious risk. Chronic heavy use can cause peripheral neuropathy and irreversible cerebellar damage. (See SOLVENT ABUSE (MISUSE).)
The hallucinogenic or psychedelic drugs include LYSERGIC ACID DIETHYLAMIDE (LSD) or acid, magic mushrooms, ecstasy (MDMA), and phencyclidine (PCP or ‘angel’ dust, mainly used in the USA). These drugs have no medicinal uses. Taken by mouth, they produce vivid ‘trips’, with heightened emotions and perceptions and sometimes with hallucinations. They are not physically addictive but can cause nightmarish bad trips during use and ?ashbacks (vivid reruns of trips) after use, and can probably trigger psychosis and even death, especially if drugs are mixed or taken with alcohol.
Stimulant drugs such as amphetamine and cocaine act like adrenaline and speed up the central nervous system, making the user feel con?dent, energetic, and powerful for several hours. They can also cause severe insomnia, anxiety, paranoia, psychosis, and even sudden death due to convulsions or tachycardia. Depression may occur on withdrawal of these drugs, and in some users this is su?ciently deterrent to cause psychological dependence. Amphetamine (‘speed’) is mainly synthesised illegally and may be eaten, sni?ed, or injected. Related drugs, such as dexamphetamine sulphate (Dexedrine), are prescribed pills that enter the black market. ECSTASY is another amphetamine derivative that has become a popular recreational drug; it may have fatal allergic effects. Cocaine and related drugs are used in medicine as local anaesthetics. Illegal supplies of cocaine (‘snow’ or ‘ice’) and its derivative, ‘crack’, come mainly from South America, where they are made from the plant Erythroxylon coca. Cocaine is usually sni?ed (‘snorted’) or rubbed into the gums; crack is burnt and inhaled.
Opiate drugs are derived from the opium poppy, Papaver somniferum. They are described as narcotic because they induce sleep. Their main medical use is as potent oral or injectable analgesics such as MORPHINE, DIAMORPHINE, PETHIDINE HYDROCHLORIDE, and CODEINE. The commonest illegal opiate is heroin, a powdered form of diamorphine that may be smoked, sni?ed, or injected to induce euphoria and drowsiness. Regular opiate misuse leads to tolerance (the need to take ever larger doses to achieve the same e?ect) and marked dependence. A less addictive oral opiate, METHADONE HYDROCHLORIDE, can be prescribed as a substitute that is easier to withdraw.
Some 75,000–150,000 Britons now misuse opiates and other drugs intravenously, and pose a huge public-health problem because injections with shared dirty needles can carry the blood-borne viruses that cause AIDS/HIV and HEPATITIS B. Many clinics now operate schemes to exchange old needles for clean ones, free of charge. Many addicts are often socially disruptive.
For help and advice see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP – National Dugs Helpline.
(See ALCOHOL and TOBACCO for detailed entries on those subjects.)... dependence
Medical ethics are embedded in cultural values which evolve. Acceptance of abortion within well-de?ned legal parameters in some jurisdictions is an example of how society in?uences the way in which perceptions about ethical obligations change. Because they are often linked to the moral views predominating in society, medical ethics cannot be seen as embodying uniform standards independent of cultural context. Some countries which permit capital punishment or female genital mutilation (FGM – see CIRCUMCISION), for example, expect doctors to carry out such procedures. Some doctors would argue that their ethical obligation to minimise pain and suffering obliges them to comply, whereas others would deem their ethical obligations to be the complete opposite. The medical community attempts to address such variations by establish-ing globally applicable ethical principles through debate within bodies such as the World Medical Association (WMA) or World Psychiatric Association (WPA). Norm-setting bodies increasingly re?ect accepted concepts of human rights and patient rights within professional ethical codes.
Practical changes within society may affect the perceived balance of power within the doctor-patient relationship, and therefore have an impact on ethics. In developed societies, for example, patients are increasingly well informed about treatment options: media such as the Internet provide them with access to specialised knowledge. Social measures such as a well-established complaints system, procedures for legal redress, and guarantees of rights such as those set out in the NHS’s Patient’s Charter appear to reduce the perceived imbalance in the relationship. Law as well as ethics emphasises the importance of informed patient consent and the often legally binding nature of informed patient refusal of treatment. Ethics re?ect the changing relationship by emphasising skills such as e?ective communication and generation of mutual trust within a doctor-patient partnership.
A widely known modern code is the WMA’s International Code of Medical Ethics which seeks to provide a modern restatement of the Hippocratic principles.
Traditionally, ethical codes have sought to establish absolutist positions. The WMA code, for example, imposes an apparently absolute duty of con?dentiality which extends beyond the patient’s death. Increasingly, however, ethics are perceived as a tool for making morally appropriate decisions in a sphere where there is rarely one ‘right’ answer. Many factors – such as current emphasis on autonomy and the individual values of patients; awareness of social and cultural diversity; and the phenomenal advance of new technology which has blurred some moral distinctions about what constitutes a ‘person’ – have contributed to the perception that ethical dilemmas have to be resolved on a case-by-case basis.
An approach adopted by American ethicists has been moral analysis of cases using four fundamental principles: autonomy, bene?cence, non-male?cence and justice. The ‘four principles’ provide a useful framework within which ethical dilemmas can be teased out, but they are criticised for their apparent simplicity in the face of complex problems and for the fact that the moral imperatives implicit in each principle often con?ict with some or all of the other three. As with any other approach to problem-solving, the ‘four principles’ require interpretation. Enduring ethical precepts such as the obligation to bene?t patients and avoid harm (bene?cence and non-male?cence) may be differently interpreted in cases where prolongation of life is contrary to a patient’s wishes or where sentience has been irrevocably lost. In such cases, treatment may be seen as constituting a ‘harm’ rather than a ‘bene?t’.
The importance accorded to ethics in daily practice has undergone considerable development in the latter half of the 20th century. From being seen mainly as a set of values passed on from experienced practitioners to their students at the bedside, medical ethics have increasingly become the domain of lawyers, academic philosophers and professional ethicists, although the role of experienced practitioners is still considered central. In the UK, law and medical ethics increasingly interact. Judges resolve cases on the basis of established medical ethical guidance, and new ethical guidance draws in turn on common-law judgements in individual cases. The rapid increase in specialised journals, conferences and postgraduate courses focused on ethics is testimony to the ever-increasing emphasis accorded to this area of study. Multidisciplinary practice has stimulated the growth of the new discipline of ‘health-care ethics’ which seeks to provide uniformity across long-established professional boundaries. The trend is to set common standards for a range of health professionals and others who may have a duty of care, such as hospital chaplains and ancillary workers. Since a primary function of ethics is to ?nd reasonable answers in situations where di?erent interests or priorities con?ict, managers and health-care purchasers are increasingly seen as potential partners in the e?ort to establish a common approach. Widely accepted ethical values are increasingly applied to the previously unacknowledged dilemmas of rationing scarce resources.
In modern debate about ethics, two important trends can be identi?ed. As a result of the increasingly high pro?le accorded to applied ethics, there is a trend for professions not previously subject to widely agreed standards of behaviour to adopt codes of ethical practice. Business ethics or the ethics of management are comparatively new. At the same time, there is some debate about whether professionals, such as doctors, traditionally subject to special ethical duties, should be seen as simply doing a job for payment like any other worker. As some doctors perceive their power and prestige eroded by health-care managers deciding on how and when to ration care and pressure for patients to exercise autonomy about treatment decisions, it is sometimes argued that realistic limits must be set on medical obligations. A logical implication of patient choice and rejection of medical paternalism would appear to be a concomitant reduction in the freedom of doctors to carry out their own ethical obligations. The concept of conscientious objection, incorporated to some extent in law (e.g. in relation to abortion) ensures that doctors are not obliged to act contrary to their own personal or professional values.... ethics
Symptoms. Spastic colon: colon held in spasm. The two main symptoms are abdominal pain and altered bowel habit. Pain relieved on going to stool or on passing wind. Diarrhoea with watery stools on rising may alternate with constipation. Sensation that the bowel is incompletely emptied. Flatulence. Passing of mucus between stools. The chronic condition may cause anaemia, weight loss and rectal blood calling for treatment of the underlying condition.
Indicated: astringents, demulcents, antispasmodics.
Treatment. If possible, start with 3-day fast.
Alternatives. Teas. (1) Combine equal parts; Agrimony (astringent), Hops (colon analgesic), Ephedra (anti-sensitive). (2) Combine equal parts; Meadowsweet (astringent) and German Chamomile (nervine and anti-inflammatory). Dose: 1 heaped teaspoon to each cup boiling water; infuse 15 minutes. 1 cup freely, as tolerated. Bilberry tea. 2 tablespoons fresh or dried Bilberries in 1 pint water simmered 10 minutes. Half-1 cup freely.
Note: Old European: Chamomile and Caraway seed tea. 1 cup morning and evening.
Decoction. Formula. Tormentil root 2; Bistort root 2; Valerian root 1. Dose: 2 teaspoons to each cup water simmered 20 minutes. Half-1 cup 3-4 times daily.
Tablets/capsules. Calamus. Cramp bark. Goldenseal. Slippery Elm, Cranesbill.
Formula. Cranesbill 2; Caraway 2; Valerian half. Dose: Powders: 750mg or half a teaspoon). Liquid Extracts: 1-2 teaspoons. Tinctures: 2-4 teaspoons. Thrice daily.
Practitioner. RX tea: equal parts herbs Peppermint, Balm and German Chamomile. Infuse 1-2 teaspoons in cup boiling water and add 3 drops Tincture Belladonna.
Formula. Tinctures. Black Catechu 2; Cranesbill 1; Hops quarter. Dose: 1-2 teaspoons in water or honey, thrice daily.
Psyllium seeds (Ispaghula). 2-5 teaspoons taken with sips of water, or as Normacol, Isogel, etc. For pain in bowel, Valerian.
Fenugreek seeds. 2 teaspoons to cup water simmered 10 minutes. Half-1 cup freely. Consume seeds. Cinnamon, tincture or essence: 30-60 drops in water 3-4 times daily.
Menstrual related irritable bowel. Evening Primrose.
Irritable Bowel Syndrome, with neurosis. Treat thyroid gland (Bugleweed, Kelp, etc).
With severe nerve stress: add CNS (central nervous system) relaxant (Hops, Ladies Slipper, Roman Chamomile)
Oil of Peppermint. A simple alternative. 3-5 drops in teaspoon honey, or in enteric-coated capsule containing 0.2ml standardised Peppermint oil B.P., (Ph.Eur.)
Intestinal antispasmodics: Valerian, Chamomile, Balm, Rosemary.
Diet. “People with IBS should stop drinking coffee as it can induce a desire to defecate.” (Hallamshire Hospital Research Team)
Dandelion coffee. Fenugreek tea. Carrot juice. Bananas mashed into a puree with Slippery Elm powder. Yoghurt. Gluten-free diet.
Supplements. Calcium lactate tablets: 2 × 300mg thrice daily at meals. Floradix. Lactobacillus acidophilus to counteract toxic bacteria. Vitamin C (2-4g). Zinc. Linusit.
Note: Serious depression may underlay the condition. Anti-depressants sometimes relieve symptoms dramatically.
Chronic cases. Referral to Gastrology Outpatient Department. ... irritable bowel syndrome (ibs)
The term innate immunity is given to the protection that we are born with, such as the skin and the mucous membranes that line the mouth, nose, throat, intestines, and vagina. It also includes antibodies, or immunoglobulins (protective proteins), that have been passed to the child from the mother. If microorganisms penetrate these defences, they encounter “cell-devouring” white blood cells called phagocytes, and other types of white cells, such as natural cellkilling (cytotoxic) cells. Microorganisms may also meet naturally produced substances (such as interferon) or a group of blood proteins called the complement system, which act to destroy the invading microorganisms.The 2nd part of the immune system, adaptive immunity, comes into play when the body encounters organisms that overcome the innate defences. The adaptive immune system responds specifically to each type of invading organism, and retains a memory of the invader so that defences can be rallied instantly in the future.
The adaptive immune system first must recognize part of an invading organism or tumour cell as an antigen (a protein that is foreign to the body). One of 2 types of response – humoral or cellular – is then mounted against the antigen.
Humoral immunity is important in the defence against bacteria. After a complex recognition process, certain B-lymphocytes multiply and produce vast numbers of antibodies that bind to antigens. The organisms bearing the antigens are then engulfed by phagocytes. Binding of antibody and antigen may activate the complement system, which increases the efficiency of the phagocytes.
Cellular immunity is particularly important in the defence against viruses, some types of parasites that hide within cells, and, possibly, cancer cells. It involves 2 types of T-lymphocyte: helper cells, which play a role in the recognition of antigens and activate the killer cells (the 2nd type of T-lymphocyte), which destroy the cells that have been invaded.
Disorders of the immune system include immunodeficiency disorders and allergy, in which the immune system has an inappropriate response to usually innocuous antigens such as pollen.
In certain circumstances, such as after tissue transplants, immunosuppressant drugs are used to suppress the immune system and thus prevent rejection of the donor tissue as a foreign organism.... immune system
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