S. Sivakumar
Drug abuse, also called substance abuse or chemical abuse, is a disorder that is characterized by a destructive pattern of using a substance that leads to significant problems or distress. Teens are increasingly engaging in prescription drug abuse, particularly narcotics (which are prescribed to relieve severe pain), and stimulant medications, which treat conditions like attention deficit disorder and narcolepsy.

Initially, drug users were look down upon as those lacking in moral values that accounted for this strange consumption (of the drug) and it was more often held that a person was not "man enough" to get away from addiction. It was first recognized to be a disease like any other, by Alcoholics Anonymous, who did pioneering work in this field as an organization, delving deep into the reasons why a person fell into and subsequently in short time lost control of himself on such usage. Dr.Jellinek's path-breaking studies helped change the very orientation one hitherto had about these alcohol/drug users (abusers). Further with the advancement of neuro-physiological science, more importantly after 1956, one  came to the conclusion that drug abuse is a chronic disease, could trouble a person for his entire life and was ultimately, curable by proper treatment. The disease of addiction was thus much better understood than in the past. What was needed therefore, more than the sympathy towards such affected persons, a due recognition and systematic treatment appropriate for such cases. These could be akin to treating patients with other health problems like sugar-control or hyper-tension, to name a few.
Types of Drugs
Drugs drastically put to wrong use are brown sugar (its inferior version is heroin) cannabis (ganja, bangh and other such categories) and even alcohol which qualifies to fall under the drug category, for the reason that it is merely a chemical in liquid form that is used to give a "high". Even thinners usable with paints and other such common material could be called drugs. There could also be a case of drug abuse, where a medically prescribed item is consumed frequently, in increased quantity and violates the prescribed amount. Persons recognize that this produces a sensation that "puts them up" and they therefore start using these constantly, not when it is actually needed as a medicine.

WHO Reports
The yearly report released by bodies like WHO normally indicates an increase/decrease in pattern of drug in use, wherein sometimes what could be more prevalent would be smoking heroin; at other times it could be  injecting cannabis. All these are to be seen more as  fluctuations in drug abuse, than anything else. There are many criteria to determine whether a person is addicted or not. These could range from physical warning signs, emotional signs to an abrupt or gradual change in the family dynamics that lead to marked changes in social behaviour. The person exhibits red and glazed eyes with poor eating and sleeping habits and may also show general lack of interest and become a victim of sudden mood changes. He may develop a strange secretiveness that keeps him away from the family. On the social side he would try to become a truant with an altogether negative attitude. But as a thumb rule it would be better if one stuck to repeated usages as a symptom, where the user is fully aware of the consequences and but is prevented by a strange inability to restrict or stop the consumption of the drug in terms of quantity, frequency and be inclined towards an insurmountable urge towards drug usage.
Vulnerability
Instead of looking at the causes for drug addiction per se', it is better to understand it as a vulnerability to addiction. That would a better term. Genetic make-up plays a vital part in forming this habit, the family and friends around a person may serve as a deterrent or cause further usage of the drug(s) thereby increasing the positive expectancy that is to be derived out of it. If there is tacit approval by those around him, then it is held as a normal habit. It is no more drug abuse ; it is only rightful "use". It is "taken" in its stride. Psycho-social factors, lack of coping skills, the mechanism of a backup of friends during immense emotional pain - any or all these may be the causes for the above-mentioned vulnerability.
Withdrawal Symptoms
Withdrawal symptoms create an uncomfortable feeling and will depend more on the drug which is consumed. The body and mind become restless, become more and more irritable, all parts of the body could be affected and there is pronounced sleep disturbance. It is similar to a pair of physical balances where one scale is at its extreme and what is strictly happening is a process of re-adjustment. If the patient goes back wanting to consume only a small quantity then the brain recalls the experiences it has had in the past and forces him to consume more and more till it provides complete satisfaction. This is a state that has to be completely avoided. It would be a reminder here that substitution of one drug by another is neither the solution nor the cure.
Treatment
Drug abuse, then is the disease of the body, the mind and the soul. Though treatment may begin medically but that alone is not enough and the patient would need an enormous amount of psychological help. If,  a person gets cornered and conquered by an intake for three valium tablets, for instance, he should be taught and educated how to pass his time without these three. It requires long-term treatment, a change in lifestyle and the involvement of the family becomes cardinal in these kinds of treatments. Care should be taken to see that the patients dignity is preserved and he should always be respected.
Prevention
Prevention is a community process and not a one-time affair or a single day affair, of taking vows and the like. Instilling mere knowledge that drugs are bad alone may not also work. Developing of coping skills, learning to say a firm "no" to drugs even when repeatedly persuaded, a good support system, echoing the message against drug addiction repeatedly at different points of time, involving all sectors of the society are some of the preventive measures to be taken, all in a truly holistic manner, if results are to be seen.
Government Initiatives
The Union Ministry of Social Justice & Empowerment, as the focal point for drug demand reduction programmes in the country, has been implementing the Scheme for Prohibition and Drug Abuse Prevention since the year 1985-86. As implementation of programmes for de-addiction and rehabilitation of drug addicts require sustained and committed/involved effort with a great degree of flexibility and innovation, a State-community (voluntary) partnership appears to be particularly strong mechanism for service delivery. Accordingly, under the Scheme, while major portion of the cost of services is borne by the Government, the voluntary organisations provide actual services through the Counselling and Awareness Centres; Deaddiction cum Rehabilitation Centres, Deaddiction Camps, and Awareness Programmes. The Ministry is assisting 361 voluntary organisations for maintaining 376 De-addiction-cum-Rehabilitation Centres and 68 Counselling and Awareness Centres all over the country. The basic objective in creating facilities for treatment, at Centres run through voluntary organisations, is to ensure that the support of the family and the community is mobilized to the maximum. To facilitate the medical treatment of hard-core addicts who require intensive long-term medical attention, 100 De-addiction Centres are being run in Government hospitals/Primary Health Centres, etc. The initiatives from the Government include maintaining of Quality Assurance and Minimum Standards ensured by developing a Manual of Minimum Standards of Services, Professional Manpower Development where National Centre for Drug Abuse Prevention (NCDAP) as an apex institution has the necessary mandate for training, research and development in the drug sector and Focused Interventions for Vulnerable Targets where The Workplace Prevention Programme (WPP), a collaborative effort of the Government, ILO, NGOs and corporate sector has come up as a result. This collaboration has led to the formation of an effective group of various stakeholders, known as ARMADA, the Association of Resource Managers against Alcohol and Drug Abuse.