Medication

# Overview
A medication, medicine or drug is any substance or combination of substances administered to human beings or animals to treat or prevent disease; alternatively to assist in medical diagnosis. Commercial medications are produced by pharmaceutical companies and are often patented. Copies of former patented drugs are called generic drugs.

# Classification
Medication can be usually classified in various ways, e.g. by its chemical properties, mode of administration, or biological system affected. An elaborate and widely used classification system is the Anatomical Therapeutic Chemical Classification System(ATC system).

# Types of medication

## For the gastrointestinal tract or digestive system
- Upper digestive tract: antacids, reflux suppressants, antiflatulents, antidopaminergics, proton pump inhibitors, H2-receptor antagonists, cytoprotectants, prostaglandin analogues
- Lower digestive tract: laxatives, antispasmodics, antidiarrhoeals, bile acid sequestrants, opioids

## For the cardiovascular system
- General: beta-receptor blocker, calcium channel blockers, diuretics, cardiac glycosides, antiarrhythmics, nitrate, antianginals, vasoconstrictor, vasodilator, peripheral activator
- Affecting Blood pressure: ACE inhibitors, angiotensin receptor blockers, alpha blocker
- Coagulation: anticoagulant, heparin, antiplatelet drug, fibrinolytic, anti-hemophilic factor, haemostatic drugs
- Atherosclerosis/cholesterol agents: hypolipidaemic agents, statins.

## For the central nervous system
hypnotic, anaesthetics, antipsychotic, antidepressant (including tricyclic antidepressants, monoamine oxidase inhibitor, lithium salt, selective serotonin reuptake inhibitor), anti-emetic, anticonvulsant and antiepileptic, anxiolytic, barbiturate, movement disorder drug, stimulant (including amphetamines), benzodiazepine, cyclopyrrolone, dopamine antagonist, antihistamine, cholinergic, anticholinergic, emetic, cannabinoids, 5-HT antagonist

## For pain & consciousness (analgesic drugs)
The main classes of painkillers are NSAIDs, opioids and various orphans such as paracetamol, tricyclic antidepressants and anticonvulsants.

## For musculo-skeletal disorders
NSAIDs (including COX-2 selective inhibitors), muscle relaxant, neuromuscular drug anticholinesterase

## For the eye
- General: adrenergic neurone blocker, astringent, ocular lubricant
- Diagnostic:  topical anesthetics, sympathomimetics, parasympatholytics, mydriatics, cycloplegics
- Anti-bacterial:  antibiotics, topical antibiotics, sulfa drugs, aminoglycosides, fluoroquinolones
- Anti-viral:
- 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
sympathomimetic, antihistamine, anticholinergic, NSAIDs, steroid, antiseptic, local anesthetic, antifungal, cerumenolyti

## For the respiratory system
bronchodilator, NSAIDs, anti-allergic, antitussive, mucolytic, decongestantcorticosteroid, beta-receptor antagonist, anticholinergic, steroid

## For endocrine problems
androgen, antiandrogen, gonadotropin, corticosteroid, growth hormone, insulin, antidiabetic (sulfonylurea, biguanide/metformin, thiazolidinedione, insulin), thyroid hormones, antithyroid drugs, calcitonin, diphosponate, vasopressin analogues

## For the reproductive system or urinary system
antifungal, alkalising agent, quinolones, antibiotic, cholinergic, anticholinergic, anticholinesterase, antispasmodic, 5-alpha reductase inhibitor, selective alpha-1 blocker, sildenafil

## For contraception
- Hormonal contraception
- Ormeloxifene
- Spermicide

## For obstetrics and gynecology
NSAIDs, anticholinergic, haemostatic drug, antifibrinolytic, Hormone Replacement Therapy, bone regulator, beta-receptor agonist, follicle stimulating hormone, luteinising hormone, LHRH gamolenic acid, gonadotropin release inhibitor, progestogen, dopamine agonist, oestrogen, prostaglandin, gonadorelin, clomiphene, tamoxifen, Diethylstilbestrol

## For the skin
emollient, anti-pruritic, antifungal, disinfectant, scabicide, pediculicide, tar products, vitamin A derivatives, vitamin D analogue, keratolytic, abrasive, systemic antibiotic, topical antibiotic, hormones, desloughing agent, exudate absorbent, fibrinolytic, proteolytic, sunscreen, antiperspirant, corticosteroid

## For infections and infestations
antibiotic, antifungal, antileprotic, antituberculous drug, antimalarial, anthelmintic, amoebicide, antiviral, antiprotozoal

## For immunology
vaccine, immunoglobulin, immunosuppressant, interferon, monoclonal antibody

## For allergic disorders
anti-allergic, antihistamine, NSAIDs

## For nutrition
tonic, iron preparation, electrolyte, parenteral nutritional supplement, vitamins, anti-obesity drug, anabolic drug, haematopoietic drug, food product drug

## For neoplastic disorders
cytotoxic drug, sex hormones, aromatase inhibitor, somatostatin inhibitor, recombinant interleukins,  G-CSF, erythropoietin

## For diagnostics
contrast media

## Legal Considerations
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.
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.

## Naming of drugs
It may be preferable to refer to drugs by their generic names rather than their brand names.

## Other/related topics
Polypharmacy: suggests that multiple use  of prescribed and non-prescribed medications, (use of 5 or more), can have adverse effects on the recipient.
Zoopharmacognosy: Animal usage of drugs and non-foods.