Methamphetamine, "meth" or "crystal meth" is a powerful central nervous system stimulant and a member of the amphetamine class of drugs. It is a synthetic (or man-made) drug with the chemical formula C _1 0 H _1 5 N that can be taken orally (swallowed), inhaled (snorted), smoked or injected. Methamphetamine is used clinically in the treatment of narcolepsy, hyperkinesia, and for blood pressure maintenance in some individuals, however it can be produced illegally using a combination of common household chemicals and over-the-counter cold remedies, and is widely abused as an illicit drug.

Reputed to aid intelligence and alertness, cocaine use is also commonly associated with erratic behavior, paranoia, and anxiety.  As the high wears off, addicts often experience very low crashes, overwhelming users with a depressive state and/or intense level of aggravation. Although physical withdrawal symptoms may be hard to notice, the drug’s absence sparks and overwhelming craving for cocaine.

Precription Drug addiction has become a growing social concern over recent years with more widespread recreational use of prescription medications falling in the opiate and benzodiazepine classes of drugs.  Common opiate prescription addictions include drugs like OxyContin, Vicodin, Norco, Dulaudid, and Methadone.  These medications are intended to be used to relieve moderate to severe pain, but their euphoric side effects have caused them to become primary drugs of abuse in modern society.

Hallucinogens, very common in the 1960's and 1970's are still a problem with modern day society and can lead to severe addiction and permanent brain damage.  The most commonly abused hallucinogens are substances like LSD, acid, mushrooms, and mescaline.  These drugs change the user's perception of themselves and their surroundings.  Read here about hallucinogens, their dangerous effects, addiction and recovery from abuse.

As with other opioids, heroin (diacetylmorphine, also diamorphine) is used as both a pain killer and a recreational drug of abuse. Frequent administration produces tolerance and physical dependence which often develops into full-blown addiction. Internationally, diacetylmorphine is controlled under Schedules I and IV of the Single Convention on Narcotic Drugs. It is illegal to manufacture, possess, or sell diacetylmorphine without a license in Belgium, Denmark, Germany, Iran, India, the Netherlands, the United States, Australia, Canada, Ireland, Pakistan, and the United Kingdom.

There are reports of marijuana (cannabis) use going back as far as the 3rd millenium B.C. In the modern world, cannabis is used for recreational, religious, spiritual and medicinal purposes.  The United Nations estimated that in 2004 roughly 4% of the world's adult population (162 million people) used cannabis annually, and roughly 0.6% (22.5 million) used it on a daily basis.

Methamphetamine, otherwise known as "meth" or "crystal meth", is a powerful stimulant of the amphetamine class of drugs. Its most common effects include increasing alertness, concentration, energy, inducing euphoria, enhancing self-esteem, and increasing libido. Methamphetamine carries a high addictive liability.  It works by activating the reward system in the brain (the mesolimbic dopamine system), triggering the release of dopamine and norepinephrine. In pharmaceutical form, methamphetamine is FDA approved for the treatment of ADHD and obesity, sold in the United States under the brand name Desoxyn™. Meth is a synthetically produced drug that has become an epidemic in American society, destroyng lives and tearing families apart.

Cocaine is a highly addictive stimulant derived from the coca plant, which is grown primarily in Bolivia, Peru, and Colombia. Since the 1880s, cocaine has been used in eye, nose, and throat surgeries as a local anesthetic for its ability to constrict blood vessels and limit bleeding. In many countries these are the only legal uses of the drug today.

Cocaine (benzoylmethylecgonine) is a central nervous system stimulant, a vasoconstrictor, an appetite suppressant, and a local anesthetic producing effects similar to other "caine" drugs (novocaine, benzocaine, lidocaine etc.). Specifically, it is a serotonin–norepinephrine–dopamine reuptake inhibitor, which mediates functionality of these neurotransmitters. Because of the way it affects the mesolimbic dopamine reward pathway, cocaine has a significant addictive liability and is therefore illegal in most countries for non-medical uses.