What is a Disease?

A disease is a disturbed state of body or mind. We generally associate word disease with physical or mental sickness. The disease can be in any part of the body and may or may not be curable. Most of the time we cure the physical illness. Mental sickness is difficult to be identified as this is a relative term and one takes notice of it only in extreme cases. Being healthy means being free of disease; both physically and mentally. It refers to the state of body and mind which is in harmony with the surroundings or environment. A perfect health is almost difficult to achieve. For time immoreal man has tried to understand the nature and causes of diseases and has tried ways to cure those diseases.

Types of Diseases
The diseases can be categorized into two basic types. Congenital, present at birth and acquired that is contracted after birth.
(i) Congenital Diseases:- Congenital diseases are present at the time of birth. Congenital diseases could be due to genetic abnormality or due to malfunctioning of any organ or system. Congenital diseases are permanent, generally not curable and may be inherited to the children.

(ii) Acquired diseases:- The acquired diseases develop after birth and can be broadly classified into two types:
(a) Communicable or infectious diseases
(b) Non communicable or non-infectious diseases. These diseases can further be divided into many types.

The agents that cause the diseases can be put in the following five categories.
(i) Biological agents or pathogens like viruses, bacteria, fungi, protozoans, etc.
(ii) Nutrient agents like minerals, carbohydrates, proteins, fats and vitamins.
(iii) Chemical agents like urea or uric acid formed in the body; or pollutants, spores and pollens present in the atmosphere.
(iv) Physical agents like heat, cold, humidity, pressure, radiation, etc.
(v) Mechanical agents like friction or other mechanical forces.

Diseases caused by Pathogens
Pathogens are disease causing living organisms like bacteria, yeasts, molds, protozoans and parasitic worms. The first study as to how they cause diseases came from the work of Robert Koch, a German physician. In 1876 he showed that the disease anthrax of sheep was due to bacteria Bacillus anthracis which existed in the pastures in the form of protective spores. He found these rod shaped bacteria in the blood vessels of infected sheep also and so came to a conclusion that sheep and cattle got these bacteria while grazing in the pastures. He isolated and grew the bacteria in the lab and inoculated them into healthy mice. The mice developed anthrax and died. On the basis of his findings, Robert Koch – the father of bacteriological technique postulated that a bacteria (microorganism) causing a disease must satisfy the following four conditions.

(i) It must found in the organisms that are infected with the disease.
(ii) One should be able to isolate it and grow it in the pure culture in the lab on the artificial medium.
(iii) When a healthy organism is inoculated with the cultured microorganism, it must contract the disease with the same symptoms.
(iv) The same microorganism should be present in huge number in the inoculated organism. It could be re-isolated from this organism

The conditions given above hold good for animal diseases as well as human diseases. They do not apply to viruses as they cannot be cultured on the artificial medium. Viruses need a living cell to multiply. The outstanding work of Koch and later of Louis Pasteur brought many infectious diseases under control.

Various ways of transmission of infectious diseases
The infectious diseases can be transmitted by various means and if not controlled can take an epidemic form and can cause many diseases. The reason for it is that each pathogen which causes the disease thrives well and multiplies in a specific medium where it does not cause the disease. Such a medium is called as reservoir of infection. The reservoir for human diseases could be other people, animals, soil or water. From these reservoirs, the diseases can be transmitted to healthy persons directly or indirectly.

(A) Direct Transmission :- The pathogens reach and infect a healthy person directly without an intermediate agent. It could be by various means like:

a. Direct contact between the infected and the healthy person. It includes diseases like small pox, chicken pox, syphilis, gonorrhea, etc. Direct contact with the discharge from the lesions, sores, skin or mucous membranes causes the infection.

b. Droplet infection: A tiny droplet is sufficient to cause an infection or a disease. Most air-borne respiratory infections like cold, influenza, whooping cough, pneumonia and tuberculosis occur in this way. The droplets emitted into the air from sneeze, cough, spit or while talking are laden with bacteria and viruses. By inhaling the air containing the droplets one gets the infection.

c. Contact with the soil containing disease causing bacteria, viruses and other organisms. Tetanus causing bacteria thrive well in soil and enter the organism through wound or injury.

d. Bite of an animal: Rabies or hydrophobia in man is caused by a virus that is transmitted through a dog bite. The virus is present in the saliva of the rapid animal and enters the healthy person through the wound.

e. Transplacental transmission: Pathogens of certain bacteria like German measles and syphilis can pass through the placenta and if mother has these diseases during pregnancy, the foetus can also contract them.

(B) Indirect Transmission :- Many times the transmission of a pathogen to a healthy person is not direct but through an intermediate agent.

a. By vectors: It refers to arthropod carriers like houseflies, cockroaches, female anopheles mosquito, etc. which carry infectious organisms and spread the diseases. Malaria is contracted by the transfer of pathogen plasmodium by the female anopheles mosquito.

b. Vehicle borne: The pathogens present in agencies like food, water, ice or blood generally enter the body through mouth. They normally infect the digestive system and hence the wastes excreted are highly infectious. The diseases transmitted through these include cholera, dysentery, etc.

c. Air borne pathogens spread by wind currents, aerosol sprays and dust. Air and dust contain number of bacterial spores that can infect organisms.

d. Fomite-borne means one gets infection by touching any article that has been in contact with the infection. The articles could be garments, toys, crockery, door handles, soaps, taps, surgical instruments and syringes.

e. Unclean hands and fingers are the source of infection for various digestive and respiratory diseases.

Effects of Alcohol

Short – term effects of Alcohol

Alcohol is rapidly absorbed in the body tissues as it does not need to be digested. It gets absorbed through the lining of the stomach and intestine and enters the blood within two minutes after being swallowed. In no time alcohol reaches all the body cells. In the cells, its oxidation begins immediately. As the cells oxidize alcohol, a large amount of heat is produced. This excess heat, not needed by the body is carried by the blood. This raises the temperature of blood and leads to increased circulation towards the skin for dissipation of heat. The skin turns rosy and the person may gets a false impression of warmth. Actually as the blood is directed towards the skin, the supply of blood to internal organs is reduced bringing a fall in their temperature. Alcohol has no value as a food as the energy released is not used in any life processes.

Long – term effects of Alcohol
Alcohol is an intoxicant and the person under its influence suffers from loss of judgement and self – control. Alcohol not only affects the individual himself but also his family and society.

Effects of Alcohol on an Individual

Effect on Central nervous system: Alcohol is a depressant and not a stimulator as many people think. Alcohol has an anaesthetic effect and releases inhibitions. Alcohol first affects the brain cortex and the person is no longer able to think clearly and judge good or bad. He suffers from loss of judgement and will power. The person may feel less inhibited. His normal restraints disappear and he loses self – control. As alcohol takes its effects, the vision gets distorted. The person may have a blurred or double vision. As alcohol reaches the cerebellum, the muscular control begins to disappear. The person is unable to walk in a straight line and walks in a clumsy gait. He becomes dizzy while standing and has a tendency to fall. Excessive intake of alcohol decreases the blood sugar level and may cause permanent damage to nerve cells.

Effects on Liver: Liver is the organ that gets most affected and damaged by excessive drinking of alcohol. In the liver, alcohol is converted into a more toxic substance, acetaldehyde. Also, liver synthesizes fats from alcohol. The fat lowers the production of metabolism of fat, protein and carbohydrates; it becomes a store house for fat. It leads to swelling of liver and a condition called fatty liver syndrome (75% of alcoholics suffers from this syndrome). Continued use of alcohol leads to serious degeneration of liver called cirrhosis. In this disease the fatty liver shrinks and hardens as liver cells are replaced by fibrous tissue.

Effects on Stomach: Stomach is another organ affected severely by excessive drinking alcohol. In the stomach, alcohol causes an increased flow of gastric juices. High doses of alcohol (more so if taken empty stomach) lead to painful inflammation of the stomach lining called gastritis.

Effects on Kidneys: The oxidation of alcohol in the cells produces water. This excess water is excreted in large amounts by the skin during heat elimination. But this leads to dehydration of tissues and greater concentration of nitrogenous wastes in the kidneys. Alcohol affects the normal elimination of wastes by kidneys.

Effects on other Body Organs: Cells oxidize most of the alcohol taken in but the rest is removed in a variety of ways. A part of alcohol is released in the lungs and is removed along with exhaled air. It gives an alcoholic a typical alcoholic breath odour. A small part of alcohol passes out into the kidneys and is eliminated in urine.

Alcohol Psychosis: In certain cases (about one in ten) alcoholism leads to a mental disorder called alcohol psychosis. Such people need the professional help of the doctors and psychiatrists and must be admitted in the mental hospital.

Symptoms of Alcohol Psychosis
Excessive intake of alcohol affects the nervous tissue. There is general deterioration of parts of brain. Often alcoholics starve themselves for long periods during drinking alcohol. The disease gets aggravated with the deficiency of complex vitamins necessary for normal nervous activity. The person suffering from alcoholic psychosis shows a confused personality. He is in a state of delirium and does not know who he is. The person suffers from hallucinations involving visual horror. As a result he may show uncontrolled trembling called delirium tremens (or D.T.'S). He may also suffer from the memory loss of recent events. The disorder can be treated only under medical supervision that needs the professional help of psychotherapists, doctors and dieticians.

Effects of Alcohol on the Family
An alcoholic neglects his family. Once addicted an alcoholic wants to have a drink alcohol, even if there is not enough money for food in the house. Even well-to-do families break and get ruined by alcohol drinking. The alcoholic does not care about the needs of his family members, his motto is to satisfy his own desire of drinking. It leads to his frustration and insecurity in his children. The person quarrels frequently when shown resistance and often becomes violent. The atmosphere of the house no longer remains peaceful and creates a number of domestic problems with the wife, children and other family members. The family of an alcoholic may suffer silently or show resistance. The neglected children may follow a wrong path and take to crime or drugs.

Effects of Alcohol on Society
An alcoholic not only harms himself but also the society pays a price for it. Accidents by drunken drivers are on increase in cities and highways. Alcohol impairs judgement and increases the reaction time. An alcoholic puts not only himself but also the people on roads at a greater risk. As alcohol drinking impairs judgement, even innocent youths are led to crime under its influence. As alcohol reduces the mental restrain and self – control, a number of corrupt practices in the society are linked to alcoholism directly or indirectly. Alcoholism has led to more violence in the society. Under the influence of alcohol, people become less tolerant, start using abusive language and react impulsively without about its repurcussions. Alcoholism spreads antisocial and illegal activities like distillation and sale of illicit or spurious liquor, drug trafficking and decline of moral values.

Alcohol, Alcoholic and Alcoholism

Alcohol

Different types of alcohol
There are various types of alcohol like methyl alcohol or wood alcohol, isopropyl alcohol and ethyl alcohol. Methyl alcohol is used as a solvent for lacquers and as an antifreeze in automobile radiators. It is highly poisonous and should not be taken. Even small quantities of it can cause blindness or death. Isopropyl alcohol is often used as rubbing alcohol. Alcohol is also poisonous and the bottles are marked as "for external use only". Ethyl alcohol or ethanol is the drinking alcohol that is consumed by the people in different forms. In this topic we will come to know about ethyl alcohol, its short term and long term effects.

Kinds of alcoholic beverages
Ethyl alcohol or ethanol (C2H5OH), also called drinking alcohol is produced by the action of yeast on sugars. The sources of sugar used are generally from fruits (like grapes) and grains (like corn, rye, barley or wheat). Ethyl alcohol is consumed as a beverage in a number of ways. Depending on the content of alcohol, there can be two types of alcoholic beverages.
(i) Fermented beverages with low content of alcohol like beer, toddy and wine.
(ii) Distilled beverages with a relatively high content of alcohol like arrack, brandy, rum, whisky, gin, vodka, etc.

Alcoholism
The term alcoholism refers to the chronic dependence on alcohol. The person who is dependent on alcohol is called an alcoholic. An alcoholic needs proper medical supervision and help from the family and friends to break off his habit and overcome the addiction. Alcoholics can be found in all sections of society. People often begin with occasional social drinking and with small doses but soon become addictive to it and take to heavy drinking. Alcohol is an intoxicant and acts as a slow poison for the body. Most people are moderate drinkers. They can take it or leave it. They often make a single drink last for quite some time so that their body can oxidize alcohol about as fast as it enters the body. This way the alcohol is lessened and they have very few visible effects. Alcoholics are heavy drinkers. With heavy drinking the amount of alcohol in their blood keeps rising and their nervous system gets affected. Their vision becomes distorted, their walk becomes wobbly and the speech gets garbled. To overcome their habit of using alcohol, alcoholics need the cooperation of their family and friends.

Reasons for Drinking
The people take to drink alcohol for a number of reasons.
(i) Social and peer group pressure.
(ii) Just for the sake of fun and excitement.
(iii) To get a feeling of independence.
(iv) As a reaction to stress – to relieve tension.
(v) As an escape from reality when life seems unpleasant temporarily.

Alcoholism and Driving
Drinking and driving do not go together. A person under the influence of alcohol may not even realize how disastrous it can be to drive at that moment. Given below are some of the effects of alcohol that are dangerous while driving.

Impairment of Judgement of distance: A person under the influence of alcohol is not able to judge the distance accurately. His ability to judge the distance is distorted.

Poor coordination between head and eyes: A drunken driver has a poor control over the vehicle. He becomes reckless driver as the coordination between his brain and eyes is impaired.

Lack of alertness: A drunken driver may fail to recognize the objects outside his vehicle. His mind is not attentive and cannot concentrate on driving.

Blurred vision: the driver has as unsteady and blurred vision. He fails to recognize various road signals like stop lights, road flashers, dividers or turns.

Increased reaction time: Reaction time is the length of a time a person takes to respond to a stimulus. The normal reaction time is about 2/3rd of a second. A drunken driver with an increased reaction time takes longer to respond to an emergency situation. Along with poor judgement, it leads to tragic accidents. If the driver suddenly sees something on the road ahead of him, he takes longer to apply brakes resulting in the accident. Many innocent people get killed or are disabled by the accidents caused by the drunken drivers and alcohol.

Careless and discourteous behaviour: A drunken driver is an erratic, and a rash driver. He seldom gives right of way and often speeds and takes risks.

Dealcoholism
An alcoholic needs a sympathetic understanding and cooperation of the family members and friends to overcome drinking. An alcoholic uses alcohol as an escape from reality problem of life. So the foremost thing during Dealcoholism is to find the problem that underlies his drinking. Alcoholic needs volunteers to help him overcome the problem rather than take to alcohol. Dealcoholism is a gradual process. A person does not leave alcohol all of sudden. He may undergo withdrawal symptoms and may need proper medical care. There are a number of voluntary and private organizations that help people overcome the habit of taking alcohol and help them lead a healthy fulfilling life. They teach them how to cope up with stress and advise not to take alcohol. Some alcoholics with mental delirium may need to be admitted to hospitals and under the care of psychologists and doctors. It may take longer for these people to overcome the problem.

Drugs as a Social Stigma

Life of the drug addicts
Drug addiction drains the body both physically and emotionally. Drug addicts feel that drugs help them, to reduce stress but actually they go through harrowing times. The drugs are expensive and are sold illegally. The whole energy of an addict is diverted to obtain the drugs by hook or crook. He becomes useless for himself and for the society. He is forced to steal, to pay the hefty price for the drugs from illegal narcotic traffic. Once addicted, a number of them take to crime to satisfy the drugs craving. The body of an addict develops tolerance and he needs larger and larger doses. As the person develops physical and psychological dependence on drugs, he craves more for the drugs and the vicious circle begins. He gets withdrawal from his family and friends and prefers the company of other addicts. Today there are thousands of addicts and a large number of them are teenagers. They get involved in the illegal activities, drug – trafficking and crime. The drug addicts are unable to work at jobs. They are always in look out for an easy way to get money which they have to get the drugs. They often suffer from malnutrition and deliberately take overdoses to forget their problems. Drug addicts not only ruin their life but their families and society also pay a heavy price for them. Drug addicts also suffer the danger of infection. Since drugs are always procured illegally, they are not prepared in sterile conditions. Also they are diluted or mixed with substances which are not sterile. Further the syringes used are dirty, hence infection is common. It could be blood infection, jaundice, hepatitis or AIDS. The moment a person chooses a path of drugs, he is on a shortest and a surest way to disaster.

Factors Leading to Drug Addiction
There are a number of factors which lead to drug addiction. Some of these are mentioned below:-

(i) Biochemical changes caused by the drugs
Large group addictive drugs even when taken in small amounts and within a short time of their use, produce noticeable biological and chemical changes in the body. These changes called as feeling of high are then desired by the person either to escape from disturbing life problems or to get relief from stress. The person then starts desiring these small short – lived high moments and starts taking more and more drugs.
(ii) Peer group and personality influence
So many youngsters take to drugs just out of curiosity and adventure to have a new sensation or a new thrill. Sometimes they fear that if they resist, their friends may reject them. Also the people who are emotionally unstable, immature or impulsive fall easily for drugs.

(iii) Environmental, social and cultural influence
There are a number of multifarious social factors that lead the people to take drugs. All sections of society, from lower to upper class can fall prey to drug addiction. It could be due to broken homes, unhealthy parental attitudes, loneliness, lack of affection, negative attitude of people around, easy access to money, living near crime dominated spots, behavioral problems at home and work place, stressful life, etc. The addicts use drugs as an escape from the problem and in the process get addicted.

Some precautionary measures to avoid drug addiction
Drug addiction is directly related to stress. Once addicted, it is a long process before one comes back to normal life. So to avoid addiction, one should try to overcome the stress by other means like:
(i) Talk to oneself and understand and accept oneself as one is.
(ii) Try to face the problem, rather than avoid or forget it by taking drugs.
(iii) Talk to the family members, friends or teachers and other adults in the community. It is always possible to avoid drugs and sort out the problems and look for ways to overcome the stress.

Deaddiction and Rehabilitation
The road to recovery of drug addicts is long and often discouragingly slow. Family members, friends and society on the whole have a very important role to play. The drug abuse is generally not found in happy, well adjusted families. It is more among people who feel insecure and stressed. Once addicted, they need proper medical care and a sympathetic attitude. Management of deaddiction is a complicated and difficult task. It cannot be done single – handedly by a psychiatrist, psychologist or a social worker. It needs an integrated approach, and a concerted effort of a group of specialists. The treatment for deaddiction occurs in phases.

Deaddiction:
The first phase of treatment is detoxification. Here, gradually the drugs are stopped and the addict is helped to overcome the withdrawal symptoms. The addict undergoes severe physical and emotional disturbances. These are taken care by giving specific medicines. Then begins the next stage of psychotherapy and counseling in which the clinical psychologist uses his/her special ways to understand and help the addict overcome his drug addiction. The individual and group counseling is given by psychologists and counselors. The treatment includes an effort to reduce the addict's stress. An addict is taught new ways to solve everyday problems. It also needs strict supervision that an addict gets adequate diet, rest and is able to relax. They pay home visits for motivating the addicts and their family members to continue the treatment. So many times if family cooperation is not there the addicts when left on their own start taking the drugs again. The family counseling is done by efficient social workers in order to change the attitude of rejection and hostility of the neighbours and other family members towards the addict. An addict needs to be accepted by the family and society.

Rehabilitation:
Once an addict has undergoes deaddiction and is accepted by the family and society, begins the next step of rehabilitation. They are given proper vocational training so that they can lead a healthy and meaningful life. The attempts are made to help them become useful members of the society. Deaddiction and rehabilitation of addicts is a long drawn process. There are a number of volunteer and government organizations that work towards this cause. In last two decades, drug addiction has spread to societies all over the world though initially it was confined to a few developing countries. Now it has become a global problem. To signify the magnitude of problem, United Nations Organization observed 26th June 1989, as the International Day Against Drug Abuse and Alcoholism.

CLASSIFICATION AND EFFECTS OF DRUGS ON HUMAN HEALTH

The psychotropic drugs act on the mind in various ways. Depending on how they act, they have been classified into four major groups given below.

(i) Sedatives and tranquillizers, e.g. valium, etc.
(ii) Opiate narcotics, e.g. opium, morphine, heroin, etc.
(iii) Stimulants, e.g. caffeine, cocaine, amphetamines, etc.
(iv) Hallucinogens, e.g. LSD, mescaline, charas, bhang, hashish, marijuana, etc.
Effects of the drugs according to classification are given below:

1 Sedatives and tranquillizers (depressant)

a. Valium, Calmpose, Trytanol
They depress the activity of central nervous system and produce a feeling of calmness and relaxation. They decrease anxiety temporarily and reduce the sensitivity to the world around the user. They bring drowsiness and in higher doses induce deep sleep. They help to relieve pain. So they are used by doctors to relieve pain, induce sleep and to reduce emotional anxiety. Tranquillizers are the drugs that reduce tension and anxiety, bring calmness without inducing sleep.

b. Barbiturates
Barbiturates are synthetic drugs commonly called as sleeping pills. They are used to decrease anxiety and induce sleep. As such they are not addictive but a person may develop emotional dependence on them. In such cases it is difficult to withdraw from them as the person suffers from withdrawal symptoms when deprived of the drug. Barbiturates have two more severe hazards in the society: They are frequently used in higher doses for suicide. They are lethal for the body when taken with alcohol, can lead to tragic death.

2 Opiate narcotics or narcotic drugs

a. Opium
It can be taken orally in powder form, or inhaled (smoked) or taken in the form of injections. Opium is extracted from the juice of white poppy capsule Papaver somniferum. It is reddish brown, has strong smell and is bitter in taste. It is eaten or smoked. People addicted to opium, show loss of weight, sterility and total loss of interest in work. They show severe withdrawal symptoms if drug is not made available thus they degrade the human health. An overdose may stop respiration and lead to death.

b. Morphine and Codeine
Morphine is the active ingredient of opium and is used to relieve pain. It is valuable as an analgesic. It leads to addiction. Codeine is a mild analgesic. In small doses it does not cause addiction. It is an ingredient of certain medicines like cough syrups.

c. Heroin
Heroin is highly addictive and so dangerous to human health that its use in medicine is also illegal. It is taken orally, inhaled or injected. It is often diluted with harmful substances before injected into the human body. Also the needles or syringes used are not sterile. Hence these drugs addicts often suffer from secondary illness like blood poisoning, formation of abscess, serum hepatitis and AIDS. As heroin addicts are dependent on the drug, failure to get it causes severe withdrawal symptoms like vomiting, diarrhea, shivering, twitching, perspiration, abdominal cramps and muscle cramps.

3 Stimulants

a. Caffeine
Caffeine is a mild stimulant and is found in the leaves of tea plant, seeds of coffee and cocoa plant. It is commonly taken in the form of beverages like tea, coffee, cocoa and cold drinks. It increases alertness and thought. Excessive use of caffeine causes addiction.

b. Cocaine
Cocaine is extracted from the leaves of the South American cocoa plant. (It is different from the beverage cocoa). Cocaine causes a feeling of excitement and increases self-confidence. It causes temporary stimulation of nervous system and feeling of enlightment. Later person gets a feeling of fear and turns violent. It is also used as local anesthesia by doctors.

c. Amphetemines
Amphetemines are synthetic drugs often used as pep pills. These are often taken by truck drivers and night workers to keep themselves awake, without realizing that these also cause blurred vision and impair judgement. Higher doses can cause hallucinations. Weight watchers use them to reduce their appetite.

4 Hallucinogens
Hallucinogens are also known as psychedelic, or mind expanding drugs. LSD, mescaline, psilocybin and products of hemp plants like charas, bhang, marijuana, hashish. Hallucinogens alter a person's thoughts, feeling and perceptions. The person claims to see sounds, and hear things that do not exist.

a. LSD (Lysergic acid diethylamide)
LSD is the most dangerous hallucinogen. It is obtained from the argot fungus. An LSD drug even in very small amounts like 1 µg per kg of body weight induces psychedelic trips. The user sees bright lights, strange shapes and a feeling of outside their bodies. It causes severe damage to the nervous system.

b. Mescaline
Mescaline is extracted from the spineless cactus that grows in south – west America. The drug is used to get kicks and has similar effects like other hallucinogens.
c. Psilocybin
Psilocybin is extracted from certain mushrooms. It is also taken to get kick and causes hallucinations.
d. Products of hemp plant charas, bhang and ganja, marijuana and hashish
All these are obtained from the dried leaves and flowers parts of the hemp plant Cannabis sativa. These drugs are commonly taken by drug users in India. The reaction depends upon the amount and strength of drug used. The user feels relaxed, elated and high. However may become moody and violent. They lose the sense of timing and judgement and see and hear objects. These drugs have dangerous often fatal effects when taken along with other drugs like heroin and when taken in combination with alcohol.

Introduction to Drugs

Drugs
Definition: By the definition, the term drug can be defined as any substance used in the composition of a medicine. In medical terms a drug is defined as any chemical substance which taken into the body, alters the way the body functions. It means a drug may modify one or more of the body's physical or mental functions.

Uses of Drugs
Drugs are used in a number of ways.
Drugs are prescribed as medicines to prevent or cure a variety of disease. Some drugs help to fight against infections.
Drugs may be used to promote better physical and mental health.
A number of drugs are used to alleviate anxiety, reduce pain or insomnia.
Drugs may be used to alter the mood. Such drugs are termed as mood – altering drugs.

The drugs should be used under medical advice only. Self – medication may be very harmful because drugs do have harmful side – effects. Some drugs like mood – altering drugs have a particular risk of a patient becoming totally dependent on them called drug dependence. They are habit forming drugs, also called as psychotropic drugs.
In this topic we will only come to know about the habit forming drugs in detail.

Psychotropic Drugs
(i) Psychotropic drugs act on the brain and affect its normal functioning. They slow down and interfere in the functioning of the nervous system.
(ii) Psychotropic drugs alter behavior, consciousness and powers of perception. They alter the mood of a person, hence are called as mood – altering drugs.
(iii) Psychotropic drugs have a visible effect on the behaviour of a person.
(iv) Psychotropic drugs impair the person's judgments.
(v) Psychotropic drugs make a person increasingly dependent on them. Therefore they are called as habit forming or addictive drugs. They lead to both physical and mental addiction.
Certain Terms Related to Habit Forming Drugs
Given below are certain terms to drug addiction which will often used in this topic.

Tolerance: - Tolerance to a drug means less response to a specific dose with repeated use. That means body has developed resistance to the effect of the drug. Now the person needs more of the drug to get the desired effect. For example, when a person takes 1 microgram of a drug for the first time, the response he gets is far more than when he takes it the hundredth time. Now he needs to take much more the amount for the same effect.

Drug Addiction: - Drug addiction means that after a drug has been taken for some time, it is very hard to give up its use. It is state of periodic and persistent urge, deterimental to the health of individual and society. The person who becomes addicted is known as addict.
An addict shows the following characteristics:
(i) A strong urge to continue taking the drug.
(ii) Progressive tolerance to the drug, that is increasing the dose of drug to get desired effects.
(iii) Physical and mental dependence on the drug.

Withdrawal Symptoms: When a drug is taken regularly for sometime, two types of addiction may occur – physical and emotional or psychological.
In physical addiction the body develops a need for the drug. When drug supply is cut off, the body reacts violently and a number of withdrawal symptoms starts appearing. These include:
(i) Severe abdominal pain or severe body ache
(ii) Muscular cramps
(iii) Headache
(iv) Fever
(v) Watering of eyes and nose
(vi) Vomiting and pain in stomach
(vii) Sleeplessness, difficulty in breathing, irregular heartbeat, etc. Such a person gets relief only when he gets more of the drugs.

Emotional or Psychological addiction: It means a person has a strong craving or urge for the drug either for pleasure r to avoid the intense physical disturbance. If the drug is not given, the addict faces severe depression and derangement. If a person is not physically addicted to a drug, he may overcome his addiction without suffering from withdrawal sickness. But usually people are addicted to a drug physically as well as emotionally. They need proper medical care to overcome their addiction.

Psychological Drug Dependence: It refers to the state of mind of a person who is so dependent on the drug that his life or activities are centered around in ensuring the supply of drug. The drug itself may or may not be addictive but the person wants to take it continuously just to enjoy its effects or to avoid the discomfort caused by its absence. Repeated use of the drug makes a patient totally dependent on them. World Health Organization (WHO) suggested the use of the term drug dependence to include the terms drug addiction or drug abuse. The drugs that cause drug dependence are called as psychotropic drugs as they act on the brain and alter behavior, consciousness power of perception.