Pharmaceutical Drugs, What Is Pharmaceutical Drugs?

A pharmaceutical drugs (medicine or medication and officially medicinal product) is any chemical substance formulated or
compounded as single active ingredient or in combination of other pharmacologically active substance, it may be in a
separate but packed in a single unit pack as combination product intended for internal, or external or for use in the medical
diagnosis, cure, treatment, or prevention of disease.

Medications are classified in various ways. One of the key divisions is between traditional small molecule drugs, usually
derived from chemical synthesis, and biopharmaceuticals, which include recombinant proteins, vaccines, blood products
used therapeutically (such as IVIG), gene therapy, and cell therapy (for instance, stem cell therapies).

Pharmaceuticals are classified in various other groups besides their origin on the basis of pharmacological properties like
mode of action and their pharmacological action or activity, route of administration, biological system affected, or therapeutic
effects. An elaborate and widely used classification system is the Anatomical Therapeutic Chemical
Classification System (ATC system). The World Health Organization keeps a list of essential medicines.

Drug discovery and drug development are complex and expensive endeavors undertaken by companies, academic
scientists, and governments.
Governments generally regulate what drugs can be marketed, how drugs are marketed, and in some jurisdictions, drug
pricing. Controversies have arisen over drug pricing and disposal of used drugs.

Etymology Drugs

"Pharmaceutical" derives from the Greek pharmakeutikos (from pharmakeutes 'druggist', from pharmakon 'drug').

Classification Drugs

Pharmaceutical or a drug is classified on the basis of their origin.
Drug from natural origin: Herbal or plant or mineral origin, some drug substances are of marine origin.

Drug from chemical as well as natural origin: Derived from partial herbal and partial chemical synthesis Chemical,
example steroidal drugs

Drug derived from chemical synthesis.
Drug derived from animal origin: For example, hormones, and enzymes.
Drug derived from microbial origin: Antibiotics

Drug derived by biotechnology genetic-engineering, hybridoma technique for example
Drug derived from radioactive substances.

One of the key classifications is between traditional small molecule drugs, usually derived from chemical synthesis, and
biologic medical products, which include recombinant proteins, vaccines, blood products used therapeutically (such as IVIG),
gene therapy, and cell therapy (for instance, stem cell therapies).

Pharmaceutical or drug or medicines are classified in various other groups besides their origin on the basis of
pharmacological properties like mode of action and their pharmacological action or activity, such as by chemical properties,
mode or route of administration, biological system affected, or therapeutic effects.

An elaborate and widely used classification system is the Anatomical Therapeutic Chemical Classification System
(ATC system). The World Health Organization keeps a list of essential medicines.

A sampling of classes of medicine includes:

Antipyretics: reducing fever (pyrexia/pyresis)
Analgesics: reducing pain (painkillers)
Antimalarial drugs: treating malaria

Antibiotics: inhibiting germ growth
Antiseptics: prevention of germ growth near burns, cuts and wounds
Mood stabilizers: lithium and valpromide
Hormone replacements: Premarin

Oral contraceptives: Enovid, "biphasic" pill, and "triphasic" pill
Stimulants: methylphenidate (Ritalin)
Tranquilizers: meprobamate, chlorpromazine, reserpine, chlordiazepoxide, diazepam, and alprazolam

Statins: lovastatin, pravastatin, and simvastatin
Types of medicines (type of pharmacotherapy)
For the gastrointestinal tract (digestive system)

Upper digestive tract: antacids, reflux suppressants, antiflatulents, antidopaminergics, proton pump
inhibitors (PPIs), H2-receptor antagonists, cytoprotectants, prostaglandin analogues
Lower digestive tract: laxatives, antispasmodics, antidiarrhoeals, bile acid sequestrants, opioid
For the cardiovascular system

General: receptor blockers ("beta blockers"), calcium channel blockers, diuretics, cardiac glycosides, antiarrhythmics,
nitrate, antianginals, vasoconstrictors, vasodilators.

Affecting blood pressure/(antihypertensive drugs): ACE inhibitors, angiotensin receptor blockers, beta-blockers,
blockers, calcium channel blockers, thiazide diuretics, loop diuretics, aldosterone inhibitors
Coagulation: anticoagulants, heparin, antiplatelet drugs, fibrinolytics, anti-hemophilic factors, haemostatic drugs

HMG-CoA reductase inhibitors (statins) for lowering LDL cholesterol inhibitors: hypolipidaemic agents.
For the central nervous system

Drugs affecting the central nervous system include: Psychedelics, hypnotics, anaesthetics, antipsychotics, antidepressants
(including tricyclic antidepressants, monoamine oxidase inhibitors, lithium salts, and selective serotonin reuptake inhibitors
(SSRIs)), antiemetics, anticonvulsants/antiepileptics,

anxiolytics, barbiturates, movement disorder (e.g., Parkinson's disease) drugs, stimulants (including amphetamines),
benzodiazepines, cyclopyrrolones, dopamine antagonists, antihistamines, cholinergics,

anticholinergics, emetics, cannabinoids, and 5-HT (serotonin) antagonists.
For pain and consciousness (analgesic drugs)

The main classes of painkillers are NSAIDs, opioids and Local anesthetics.
For musculo-skeletal disorders

The main categories of drugs for musculoskeletal disorders are: NSAIDs (including COX-2 selective inhibitors),
muscle relaxants, neuromuscular drugs, and anticholinesterases.

Drugs For the Eye

General: adrenergic neurone blocker, astringent, ocular lubricant
Diagnostic: topical anesthetics, sympathomimetics, parasympatholytics, mydriatics, cycloplegics
Antibacterial: antibiotics, topical antibiotics, sulfa drugs, aminoglycosides, fluoroquinolones
Antiviral drug
Anti-fungal: imidazoles, polyenes

Anti-inflammatory: NSAIDs, corticosteroids
Anti-allergy: mast cell inhibitors

Anti-glaucoma: adrenergic agonists, beta-blockers, carbonic anhydrase inhibitors/hyperosmotics, cholinergics, miotics,
parasympathomimetics, prostaglandin agonists/prostaglandin inhibitors. nitroglycerin
For the ear, nose and oropharynx

Antibiotics, sympathomimetics, antihistamines, anticholinergics, NSAIDs, corticosteroids, antiseptics, local anesthetics,
antifungals, cerumenolytic

Drugs For the respiratory system

bronchodilators, antitussives, mucolytics, decongestants
inhaled and systemic corticosteroids, Beta2-adrenergic agonists, anticholinergics,
Mast cell stabilizers. Leukotriene antagonists

Drugs For endocrine problems

androgens, antiandrogens, gonadotropin, corticosteroids, human growth hormone, insulin, antidiabetics
(sulfonylureas, biguanides/metformin, thiazolidinediones, insulin), thyroid hormones, antithyroid drugs, calcitonin,
diphosponate, vasopressin analogues

Drugs For the reproductive system or urinary system

antifungal, alkalinizing agents, quinolones, antibiotics, cholinergics, anticholinergics, antispasmodics,
5-alpha reductase inhibitor, selective alpha-1 blockers, sildenafils, fertility medications

Drugs For contraception

Hormonal contraception
Ormeloxifene
Spermicide
For obstetrics and gynecology

NSAIDs, anticholinergics, haemostatic drugs, antifibrinolytics, Hormone Replacement Therapy (HRT), bone regulators,
beta-receptor agonists, follicle stimulating hormone, luteinising hormone, LHRH

gamolenic acid, gonadotropin release inhibitor, progestogen, dopamine agonists, oestrogen, prostaglandins, gonadorelin,
clomiphene, tamoxifen, Diethylstilbestrol

Drugs For The Skin

emollients, anti-pruritics, antifungals, disinfectants, scabicides, pediculicides, tar products, vitamin A derivatives,
vitamin D analogues,

keratolytics, abrasives, systemic antibiotics, topical antibiotics, hormones, desloughing agents, exudate absorbents,
fibrinolytics, proteolytics,
sunscreens, antiperspirants, corticosteroids, immune modulators

Drugs For infections and infestations

antibiotics, antifungals, antileprotics, antituberculous drugs, antimalarials, anthelmintics, amoebicides, antivirals,
antiprotozoals.

Drugs For the immune system

vaccines, immunoglobulins, immunosuppressants, interferons, monoclonal antibodies

For allergic disorders

anti-allergics, antihistamines, NSAIDs, Corticosteroids

For nutrition

Tonics, electrolytes and mineral preparations (including iron preparations and magnesium preparations),
parenteral nutritions, vitamins, anti-obesity drugs,
anabolic drugs, haematopoietic drugs, food product drugs

For neoplastic disorders

cytotoxic drugs, therapeutic antibodies, sex hormones, aromatase inhibitors, somatostatin inhibitors,
recombinant interleukins, G-CSF, erythropoietin

For diagnostics

contrast media
For euthanasia
See also: Barbiturate Other non-therapeutical uses and barbiturates
An euthanaticum is used for euthanasia and physician-assisted suicide.

Euthanasia is not permitted by law in many countries, and consequently medicines will not be licensed for this
use in those countries.

Administration

Administration is the delivery of a pharmaceutical drug to a patient. There are three major categories of drug administration;
enteral (taking medication orally),

parenteral (introducing the medication directly to the circulatory system), and other
(which includes introducing medication through intranasal, topical, inhalation, and rectal means).

It can be performed in various dosage forms such as pills, tablets, or capsules.
There are many variations in the routes of administration, including intravenous (into the blood through a vein) and oral
administration (through the mouth).

They can be administered all at once as a bolus, at frequent intervals or continuously.
Frequencies are often abbreviated from Latin, such as every 8 hours reading Q8H from Quaque VIII Hora.

Drug discovery

In the fields of medicine, biotechnology and pharmacology, drug discovery is the process by which new candidate
medications are discovered.

Historically, drugs were discovered through identifying the active ingredient from traditional remedies or by serendipitous
discovery. Later chemical libraries of synthetic small molecules,
natural products or extracts were screened in intact cells or whole organisms to identify substances that have a desirable

therapeutic effect in a process known as classical pharmacology.
Since sequencing of the human genome which allowed rapid cloning and synthesis of large quantities of purified proteins,
it has become common practice to use high throughput screening

of large compounds libraries against isolated biological targets which are hypothesized to be disease modifying in a process
known as reverse pharmacology. Hits from these screens are then
tested in cells and then in animals for efficacy. Even more recently, scientists have been able to understand the shape
of biological molecules at the atomic level, and to use that
knowledge to design (see drug design) drug candidates.

Modern drug discovery involves the identification of screening hits, medicinal chemistry and optimization of those hits to
increase the affinity, selectivity (to reduce the potential of side effects),

efficacy/potency, metabolic stability (to increase the half-life), and oral bioavailability. Once a compound that fulfills
all of these requirements has been identified, it will begin the process of drug
development prior to clinical trials. One or more of these steps may, but not necessarily, involve computer-aided drug design.

Despite advances in technology and understanding of biological systems, drug discovery is still a lengthy, "expensive,
difficult, and inefficient process" with low rate of new therapeutic discovery.

In 2010, the research and development cost of each new molecular entity (NME) was approximately US$1.8 billion.
Drug discovery is done by pharmaceutical companies, with research assistance
from universities. The "final product" of drug discovery is a patent on the potential drug.

The drug requires very expensive Phase I, II and III clinical trials, and most of them fail.
Small companies have a critical role, often then selling the rights to larger companies that have the resources to run the
clinical trials.

Development

Drug development is a blanket term used to define the process of bringing a new drug to the market once a lead
compound has been identified through the process of drug discovery.

It includes pre-clinical research (microorganisms/animals) and clinical trials (on humans) and may include the step of
obtaining regulatory approval to market the drug.

Regulation

The regulation of drugs varies by jurisdiction. In some countries, such as the United States, they are regulated at the
national level by a single agency. In other jurisdictions they are regulated at the state level, or at both state and national

levels by various bodies, as is the case in Australia. The role of therapeutic goods regulation is designed mainly to protect
the health and safety of the population. Regulation is aimed at ensuring the safety, quality, and efficacy of the therapeutic goods
which are covered under the scope of the regulation.

In most jurisdictions, therapeutic goods must be registered before they are allowed to be marketed.
There is usually some degree of restriction of the availability of certain therapeutic goods depending on their risk to
consumers.

Depending upon the jurisdiction, medications may be divided into over-the-counter drugs (OTC) which may be available
without special restrictions, and prescription only medicine (POM), which must be prescribed by a licensed medical
practitioner. The precise distinction between OTC and prescription depends on the legal jurisdiction.

A third category, behind-the-counter medications (BTMs), is implemented in some jurisdictions. BTMs do not require a
prescription, but must be kept in the dispensary, not visible to the public, and only be sold by a pharmacist or pharmacy

technician. Doctors may also prescribe prescription drugs for off-label use - purposes which the drugs were not originally
approved for by the regulatory agency. The Classification of Pharmaco-Therapeutic Referrals helps guide the referral process
between pharmacists and doctors.

The International Narcotics Control Board of the United Nations imposes a world law of prohibition of certain medications.
They publish a lengthy list of chemicals and plants whose trade and consumption (where applicable) is forbidden.

OTC medications are sold without restriction as they are considered safe enough that most people will not hurt themselves
accidentally by taking it as instructed. Many countries, such as the United Kingdom have a third category of pharmacy
medicines which can only be sold in registered pharmacies, by or under the supervision of a pharmacist.