Sunday, January 25, 2015

Drugs



In pharmacology, a drug is "a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being." Pharmaceutical drugs may be used for a limited duration, or on a regular basis for chronic disorders.In other words,Drugs are articles that are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in humans or animals, and any articles other than food, water, or oxygen that are intended to affect the mental or body function of humans or animals. Drugs have been defined to include such things as herb tonics, cold salves, laxatives, weight-reduction aids, vitamins, and even blood. Narcotics are defined by laws as substances that either stimulate or dull an individual's senses, and that ordinarily become habit-forming (i.e., addictive) when used over time. Manufacture and sales of drugs are regulated by the Drug Regulatory bodies.The regulation of narcotics falls into two areas. Legal narcotics are regulated by the laws and are generally available only with a physician's prescription. The production, possession, and sale of illegal narcotics—commonly called controlled substances—are banned by statutes.

Recreational drugs are chemical substances that affect the central nervous system, such as opioids or hallucinogens.Alcohol, nicotine, and caffeine are the most widely consumed psychotropic drugs worldwide.These are chemicals that alter, block, or mimic chemical reactions in the brain. This causes an alteration of the body's normal processes, causing physical (Faster heartbeat, deeper respiration etc.), or mental (Elevated mood, new thought processes etc.) changes. 

Nootropics, also commonly referred to as "smart drugs", are drugs that are claimed to improve human cognitive abilities. Nootropics are used to improve memory, concentration, thought, mood, learning, and many other things. Some nootropics are now beginning to be used to treat certain diseases such as attention-deficit hyperactivity disorder, Parkinson's disease, and Alzheimer's disease. They are also commonly used to regain brain function lost during aging. Similarly, drugs such as steroids improve human physical capabilities and are sometimes used (legally or not) for this purpose, often by professional athletes.

In the scientific community, drugs are defined as substances that can affect a human's or animal's biological and neurological states. They may be organic, such as the chemical tetrahydrocannabinol (THC), which occurs naturally in marijuana; or synthetic, such as amphetamines or sedatives, which are manufactured in laboratories. Drugs can be swallowed, inhaled through the nostrils, injected with a needle, applied to the skin, taken as a suppository, or smoked. Scientists categorize drugs according to their effects. Among their categories are analgesics, which kill pain, and psychoactive drugs, which alter the mind or behavior. Some psychoactive substances produce psychological highs or lows according to whether they are stimulants or depressants, respectively. Others, called hallucinogens, produce psychedelic states of consciousness; lysergic acid diethylamide (LSD) and mescaline are examples of such drugs. Marijuana is placed in its own category.

Administering drugs

Drugs, both medicinal and recreational, can be administered in a number of ways. Many drugs can be administered in a variety of ways rather than just one.

Bolus is the administration of a medication, drug or other compound that is given to raise its concentration in blood to an effective level. The administration can be given intravenously, by intramuscular, intrathecal or subcutaneous injection.

Inhaled, (breathed into the lungs), as an aerosol or dry powder. (This includes smoking a substance)

Injected as a solution, suspension or emulsion either: intramuscular, intravenous, intraperitoneal, intraosseous.

Insufflation, or snorted into the nose.

Orally, as a liquid or solid, that is absorbed through the intestines.

Rectally as a suppository, that is absorbed by the rectum or colon
.
Sublingually, diffusing into the blood through tissues under the tongue.

Topically, usually as a cream or ointment. A drug administered in this manner may be given to act locally or systemically.

Vaginally as a suppository, primarily to treat vaginal infections.

Types of Drugs 

Drugs can be classified in many ways. For example, they can be classified according to:

Uses (medicinal or recreational)
Effect on the body (the specific effect on the central nervous system)
Source of the substance (synthetic or plant)
Legal status (legal/illegal)
Risk status (dangerous/safe)

One of the most common and useful ways of classifying a drug is by the effect that it has on a person's central nervous system. The brain is the major part of the central nervous system, and this is where psycho-active drugs have their main effect.

The below sub-section summarises the major classifications of drugs including stimulants, depressants and hallucinogens. The group 'others' includes those psycho-active drugs that do not fit neatly in any other category. Some drugs can be classified in a number of categories, e.g. cannabis and ecstasy.

Classifying drugs by their effect on CNS

Stimulants

Tend to speed up the activity of a person's central nervous system (CNS) including the brain.

These drugs often result in the user feeling more alert and more energetic.

Examples include:

Amphetamines
Cocaine
Pseudoephidrine (found in medications such as Sudafed, Codral Cold and Flu)
Nicotine
Caffeine

Depressants (also known as relaxants/Sedatives)

Tend to slow down the activity of the CNS, which often results in the user feeling less pain, more relaxed and sleepy.

These symptoms may be noticeable when a drug is taken in large amounts.

It is important to note that the term 'depressant' is used to describe the effect on the CNS, not mood.

CNS depressants are more likely to result in euphoria than depression, especially in moderate use.

Examples include:

Alcohol
Major tranquillisers
Benzodiazepines (e.g. Valium, Temazepam) Opioids (heroin, morphine)
Volatile substances (can also be classified as 'other' (glue, petrol, and paint).

Hallucinogens

Have the ability to alter a user's sensory perceptions by distorting the messages carried in the CNS. A common example is LSD (trips).

Hallucinogens alter one's perceptions and states of consciousness.

Examples include:

LSD
Psilocybin (magic mushrooms)
Mescaline (peyote cactus)

Other

Includes psycho-active drugs that do not fit neatly into one of the other categories, but which are clearly psycho-active, such as antidepressants (e.g. Zoloft) and mood stabilisers (e.g. Lithium).

Examples include:

MDMA (ecstasy)*
Cannabis*
Volatile substances (petrol, glue, paint)

* Both ecstasy and cannabis can produce hallucinations, especially in cases of heavy use, or inexperienced users. However they are usually considered primarily as CNS stimulants and depressants respectively, as these effects are almost always present.

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