psychoactive drug uses effect Addiction and treatment

what are  psychoactive drug

A psychoactive drug, psychopharmaceutical, or psychotropic is a chemical substance that changes brain function and results in alterations in perception, mood, or consciousness.These substances may be used recreationally, to purposefully alter one's consciousness, or, as entheogens, for ritual, spiritual, or shamanic purposes, as a tool for studying or augmenting the mind. Some categories of psychoactive drugs, which have medical therapeutic value, are prescribed by medical doctors and other healthcare professionals. Examples include anesthetics, analgesics, hormonal preparations, anticonvulsant and antiparkinsonian drugs or drugs used for the treatment of neuropsychiatric  disorders, as hypnotic drugs, anxiolytic and some stimulant medications used in ADHD and some sleep disorders. There are also some psychoactive substances used in the detoxification and rehabilitation programs for psychoactive drug users.

main  psychoactive drug 

cocaine
crack cocaine
methylphenidate (Ritalin)
ephedrine
MDMA (Ecstasy)
mescaline (cactus)
LSD blotter
psilocybin mushroom (Psilocybe cubensis)
Salvia divinorum
diphenhydramine (Benadryl)
Amanita muscaria mushroom
Tylenol 3 (contains codeine)
codeine with muscle relaxant
pipe tobacco
bupropion (Zyban)
cannabis
hashish

Psychoactive substances often bring about subjective (although these may be objectively observed) changes in consciousness and mood that the user may find rewarding and pleasant (e.g. euphoria or a sense of relaxation) or advantageous (e.g. increased alertness) and are thus reinforcing. Substances which are both rewarding and positively reinforcing have the potential to induce a state of addiction – compulsive drug use despite negative consequences – when used consistently in excess.

Purposes

Psychoactive substances are used by humans for a number of different purposes to achieve a specific end. These uses vary widely between cultures. Some substances may have controlled or illegal uses while others may have shamanic purposes, and still others are used medicinally

Psychoactive drugs are divided into different groups according to their pharmacological effects. Commonly used psychoactive drugs and groups:

Anxiolytics

Example: Benzodiazepine

Euphoriants

Example: MDMA (Ecstasy), MDA, 6-APB, Indopan

Stimulants ("uppers"). This category comprises substances that wake one up, stimulate the mind, and may even cause euphoria, but do not affect perception.

Examples: amphetamine, caffeine, cocaine, nicotine

Depressants

 ("downers"), including sedatives, hypnotics, and narcotics. This category includes all of the calmative, sleep-inducing, anxiety-reducing, anesthetizing substances, which sometimes induce perceptual changes, such as dream images, and also often evoke feelings of euphoria.

Examples: ethanol (alcoholic beverages), opioids, barbiturates, benzodiazepines.

Hallucinogens, including psychedelics, dissociatives and deliriants. This category encompasses all those substances that produce distinct alterations in perception, sensation of space and time, and emotional states

Examples: psilocybin, LSD, Salvia divinorum and nitrous oxide.

uses of psychoactive drug 

Anesthesia

General anesthetics are a class of psychoactive drug used on people to block physical pain and other sensations. Most anesthetics induce unconsciousness, allowing the person to undergo medical procedures like surgery without the feelings of physical pain or emotional trauma.

To induce unconsciousness, anesthetics affect the GABA and NMDA systems. For example, halothane is a GABA agonist.and ketamine is an NMDA receptor antagonist

Pain management

Psychoactive drugs are often prescribed to manage pain. The subjective experience of pain is primarily regulated by endogenous opioid peptides. Thus, pain can often be managed using psychoactives that operate on this neurotransmitter system, also known as opioid receptor agonists

Mental disorders

Psychiatric medications are psychoactive drugs prescribed for the management of mental and emotional disorders, or to aid in overcoming challenging behavior.There are six major classes of psychotropic medications

Antidepressants 

treat disparate disorders such as clinical depression, dysthymia, anxiety, eating disorders and borderline personality disorder.

Stimulants, which are used to treat disorders such as attention deficit disorder and narcolepsy and to suppress the appetite.

Antipsychotics, which are used to treat psychotic symptoms, such as those associated with schizophrenia or severe mania.

Mood stabilizers, 

which are used to treat bipolar disorder and schizoaffective disorder.

Anxiolytics, which are used to treat anxiety disorders.

Depressants, which are used as hypnotics, sedatives, and anesthetics, depending upon dosage.

In addition, several psychoactive substances are currently employed to treat various addictions. These include acamprosate or naltrexone in the treatment of alcoholism, or methadone or buprenorphine maintenance therapy in the case of opioid addiction

Effects on human  

Psychoactive drugs operate by temporarily affecting a person's neurochemistry, which in turn causes changes in a person's mood, cognition, perception and behavior. There are many ways in which psychoactive drugs can affect the brain. Each drug has a specific action on one or more neurotransmitter or neuro receptor in the brain.

Drugs that increase activity in particular neurotransmitter systems are called agonists. They act by increasing the synthesis of one or more neurotransmitters, by reducing its reuptake from the synapses, or by mimicking the action by binding directly to the postsynaptic receptor. Drugs that reduce neurotransmitter activity are called antagonists, and operate by interfering with synthesis or blocking postsynaptic receptors so that neurotransmitters cannot bind to them

Addiction and dependence

Psychoactive drugs are often associated with addiction or drug dependence. Dependence can be divided into two types: psychological dependence, by which a user experiences negative psychological or emotional withdrawal symptoms (e.g., depression) and physical dependence, by which a user must use a drug to avoid physically uncomfortable or even medically harmful physical withdrawal symptoms.Drugs that are both rewarding and reinforcing are addictive; these properties of a drug are mediated through activation of the mesolimbic dopamine pathway, particularly the nucleus accumbens. Not all addictive drugs are associated with physical dependence, e.g., amphetamine, and not all drugs that produce physical dependence are addictive drugs, e.g., caffeine.