Drug abuse is a serious public health problem that affects almost every community and family in some way. Each year drug abuse causes millions of serious illnesses or injuries among people. Drug abuse also plays a role in many major social problems, such as drugged driving, violence, stress, and child abuse. Drug abuse can lead to homelessness, crime, and missed work or problems with keeping a job. It harms unborn babies and destroys families. There are different types of treatment for drug abuse. But the best is to prevent drug abuse in the first place. Abused drugs include:
Many people do not understand why people become addicted to drugs or how drugs change the brain to foster compulsive drug abuse. They mistakenly view drug abuse and addiction as strictly a social problem and may characterize those who take drugs as morally weak. One very common belief is that drug abusers should be able to just stop taking drugs if they are only willing to change their behavior.
What people often underestimate is the complexity of drug addiction -- that it is a disease that impacts the brain, and because of that, stopping drug abuse is not simply a matter of willpower. Through scientific advances we now know much more about how exactly drugs work in the brain, and we also know that drug addiction can be successfully treated to help people stop abusing drugs and resume productive lives. 
Islam’s approach to health and well-being means that anything that is harmful or mostly harmful, is forbidden. Therefore, Islam takes an uncompromising stand towards Alcohol or Tobacco and forbids its consumption in either small or large quantities.
Allaah says: “he allows them as lawful At Tayyibaat (i.e. all good and lawful as regards things, deeds, beliefs, persons and foods), and prohibits them as unlawful Al Khabaa’ith (i.e. all evil and unlawful as regards things, deeds, beliefs, persons and foods)” Quran Surah al-A’raaf 7:157All forms of smoking are kinds of khabaa’ith (evil and unlawful things), and they include harmful and intoxicating substances. It is haraam to deal with it in any way, whether one inhales it, chews it or deals with it in any of its other forms.
Prophet Muhammad (ﷺ) said: “Every intoxicant is unlawful and every intoxicant is Khamr.” SAHIH MUSLIM 4966 and SUNAN NASEE Vol. 6: 5585 Ibn ‘Umar (R) reported Allah’s Messenger (ﷺ) as saying: Every intoxicant is Khamr and every intoxicant is forbidden. He who drinks wine in this world and dies while he is addicted to it, not having repented, will not be given a drink in the Hereafter. SAHIH MUSLIM 4963 AND ABU DAWOOD 3671 
Addiction is a chronic, often relapsing brain disease that causes compulsive drug seeking and use, despite harmful consequences to the addicted individual and to those around him or her. Although the initial decision to take drugs is voluntary for most people, the brain changes that occur over time challenge an addicted person’s self-control and hamper his or her ability to resist intense impulses to take drugs.
Fortunately, treatments are available to help people counter addiction’s powerful disruptive effects. Research shows that combining addiction treatment medications with behavioral therapy is the best way to ensure success for most patients. Treatment approaches that are tailored to each patient’s drug abuse patterns and any co-occurring medical, psychiatric, and social problems can lead to sustained recovery and a life without drug abuse.
Similar to other chronic, relapsing diseases, such as diabetes, asthma, or heart disease, drug addiction can be managed successfully. And as with other chronic diseases, it is not uncommon for a person to relapse and begin abusing drugs again. Relapse, however, does not signal treatment failure—rather, it indicates that treatment should be reinstated or adjusted or that an alternative treatment is needed to help the individual regain control and recover.
Drugs contain chemicals that tap into the brain’s communication system and disrupt the way nerve cells normally send, receive, and process information. There are at least two ways that drugs cause this disruption:
(1) by imitating the brain’s natural chemical messengers and
(2) by over stimulating the “reward circuit” of the brain.
Some drugs (e.g., marijuana and heroin) have a similar structure to chemical messengers called neurotransmitters, which are naturally produced by the brain. This similarity allows the drugs to “fool” the brain’s receptors and activate nerve cells to send abnormal messages.
Other drugs, such as cocaine or methamphetamine, can cause the nerve cells to release abnormally large amounts of natural neurotransmitters (mainly dopamine) or to prevent the normal recycling of these brain chemicals, which is needed to shut off the signaling between neurons. The result is a brain awash in dopamine, a neurotransmitter present in brain regions that control movement, emotion, motivation, and feelings of pleasure. The overstimulation of this reward system, which normally responds to natural behaviors linked to survival (eating, spending time with loved ones, etc.), produces euphoric effects in response to psychoactive drugs. This reaction sets in motion a reinforcing pattern that “teaches” people to repeat the rewarding behavior of abusing drugs.
As a person continues to abuse drugs, the brain adapts to the overwhelming surges in dopamine by producing less dopamine or by reducing the number of dopamine receptors in the reward circuit. The result is a lessening of dopamine’s impact on the reward circuit, which reduces the abuser’s ability to enjoy not only the drugs but also other events in life that previously brought pleasure. This decrease compels the addicted person to keep abusing drugs in an attempt to bring the dopamine function back to normal, but now larger amounts of the drug are required to achieve the same dopamine high—an effect known as tolerance.
Long-term abuse causes changes in other brain chemical systems and circuits as well. Glutamate is a neurotransmitter that influences the reward circuit and the ability to learn. When the optimal concentration of glutamate is altered by drug abuse, the brain attempts to compensate, which can impair cognitive function. Brain imaging studies of drug-addicted individuals show changes in areas of the brain that are critical to judgment, decision making, learning and memory, and behavior control. Together, these changes can drive an abuser to seek out and take drugs compulsively despite adverse, even devastating consequences—that is the nature of addiction.
No single factor can predict whether a person will become addicted to drugs. Risk for addiction is influenced by a combination of factors that include individual biology, social environment, and age or stage of development. The more risk factors an individual has, the greater the chance that taking drugs can lead to addiction. For example:
Drug addiction is a preventable disease. Results from NIDA-funded research have shown that prevention programs involving families, schools, communities, and the media are effective in reducing drug abuse. Although many events and cultural factors affect drug abuse trends, when youths perceive drug abuse as harmful, they reduce their drug taking. Thus, education and outreach are key in helping youth and the general public understand the risks of drug abuse. Teachers, parents, and medical and public health professionals must keep sending the message that drug addiction can be prevented if one never abuses drugs. 
Substance abuseis a pandemic in the United States. From the abuse of seemingly innocent substances such as marijuana and alcohol to the abuse of street drugs like cocaine and heroin, substance abuse costs individuals substantially, and it costs the nation as a whole. According to the U.S. Department of Health and Human Services:
It’s not surprising that substance abuse comes with such a high price tag when you consider all the health, legal, criminal, and personal issues that often come in its wake.
In 2012, nearly 24 million Americans, age 12 and older, had abused an illicit drug, per the National Institute on Drug Abuse (NIDA). Marijuana is still the most frequently abused drug, with more than 20 million Americans citing use of marijuana within the prior 30 days, according to the National Survey on Drug Use and Health (NSDUH), and more than 8 million people admitting to using marijuana on a near daily basis.
Drugs work by stimulating various parts of the human body, including certain areas of the brain. The many different types and classifications of drugs produce a variety of short-term effects, but the most common ones include increased heart rate, high blood pressure, dizziness, tremors, mood changes and paranoia. In high dosages, the risk for more dangerous effects increases, and the potential for heart attack, stroke, respiratory failure and coma increase.
In the long-term, substance abuse may lead to mental and physical effects that will require treatment to resolve. These effects can include:
If you are taking drugs, it is possible you believe that you can manage the effects of the drugs and that you can deal with the impact it has on your life. Taking drugs might make you feel good, and there may not even appear to be any immediate consequences to taking the drug.
Sometimes some of these impacts might appear over time and as circumstances in your life or your use of drugs changes. It may be useful to stop and re-examine the impact of your drug use on your life now and see whether the negatives are outweighing the positives.
You may find it useful to go through the list of possible life impacts below as a prompt. It may also be helpful to talk with someone you trust, for example, a friend, counsellor or family member.
In general – your drug use might have impact on your life in ways you might not expect. What were things like before you started using? How does using affect your life now? How would you like things to be different in the future?
Your relationships – are you finding that there has been any negative change in your relationships? When drug use is an ongoing problem, conflict between friends and partners, and family breakdown can be more common.
Safety – do you ever find yourself in situations where you do not feel entirely in control of your actions? Being under the influence of drugs could put you at risk of being in danger in certain circumstances. Buying drugs or trying to get the money to buy them can also put you at risk of harm.
School / TAFE / university – do you feel you are managing your study commitments? You might not immediately notice the impact that your lifestyle is having on your study. Keeping up with your assignments and concentrating in class are two examples of how your study can be affected by drug use.
Employment – have you or a friend lost a job recently as a result of not being able to do your job because you were drug-affected? The after effects of using drugs (coming down or feeling scattered) can reduce your ability to work in a job, they often place you in danger of hurting yourself or others at work, and can reduce your job prospects too.
Financial pressures – have you found yourself struggling to pay bills or buy necessities because you have spent your pay or allowance on drugs? Have you ever thought about just how much you would save if you didn't use drugs?
Using drugs regularly can become really expensive. In the extreme, when people are highly dependent on drugs, funding their habit can be their top priority and can lead to crime, or risking everything on gambling, only to end up losing.
Dependence – are you finding it difficult to function without taking drugs? When you take drugs there is a risk that you will become dependent on them. This means that you might feel like you cannot operate without it or that you are spending a lot of time and energy finding and using the drug. Another sign of dependence can be when you start taking more of the drug as a way to cope, or avoid, the symptoms related to the comedown.
Violence – have you done something you would not normally do when not taking drugs? Some drugs, like amphetamines, can increase the likelihood of acting in a violent way, or being the victim of violence.
Homelessness – have your parents threatened to kick you out of home, or are you finding it hard to pay your rent? If you are spending your money on drugs you might find that there is not much money left for living (paying rent, buying food, or having the money to see a doctor or buy medicine when you get sick).
Stress – feeling stressed instead of relaxed after taking drugs? You might think that using certain drugs will help you relax and forget about the things that are causing you stress. However, changing the way the body and mind work with drugs is a stress in itself, and you could experience tension, anxiety, paranoia and other symptoms which only increase the feelings of stress.
Psychosis – have you or anyone you know ever lost touch with what is real? A number of drugs can trigger psychosis, which is a mental disorder where you lose touch with reality.
Depression – have you ever felt depressed after taking drugs, or felt that taking drugs worsens existing depression? Feeling low after using some drugs is common (including alcohol). This can be due to the effect of the drug itself or because of things that happened when you were using them.
Injuries and accidents – ever had an accident after taking drugs? When you are under the influence of drugs you might find yourself doing things that you would not normally do, which can increase your chance of getting hurt or having an accident.
Sexually Transmitted Infections (STI’s) or unwanted pregnancy – ever forgotten to use a condom when you were under the influence of drugs? Under the influence you are less likely to remember to use protection which can result in you or the person you have sex with contracting an STI or getting pregnant.
Damage to internal organs – have you considered the impact on your body? Heavy use of some drugs can damage the liver, brain, lungs, throat and stomach.
Risk of infectious disease – have you considered the risk of disease through drug paraphernalia? Sharing needles is a major risk for getting diseases like hepatitis B or C, or HIV, which are all spread through blood-to-blood transmission. 
When drug use, abuse, and dependence occur, you are more likely to have changes in your behavior than to have physical symptoms.
These signs don't always mean a person is using drugs. The behavior could be because of work or school stress, or it could be a sign of depression or another medical problem. But behavior changes like these are common in people who abuse drugs.
If you think you or a loved one might have a drug problem, use this short quiz to check your drug use:
Assess Your Drug Use - Physical signs of drug abuse or dependence
Marijuana smoke contains 50% to 70% more cancer-causing substances than tobacco smoke. One major research study reported that a single cannabis joint could cause as much damage to the lungs as up to five regular cigarettes smoked one after another. Long-time joint smokers often suffer from bronchitis, an inflammation of the respiratory tract.
The drug can affect more than your physical health. Studies in Australia in 2008 linked years of heavy marijuana use to brain abnormalities. This is backed up by earlier research on the long-term effects of marijuana, which indicate changes in the brain similar to those caused by long-term abuse of other major drugs. And a number of studies have shown a connection between continued marijuana use and psychosis. 
Alcoholkills more teenagers than all other drugs combined. It is a factor in the three leading causes of death among 15- to 24-year-olds: accidents, homicides and suicides.