Pharmacology

Pharmacology (in Greek: pharmacon (φάρμακον) is drug, and logos (λόγος) is science) is the study of how chemical substances interact with living systems. If these substances have medicinal properties, they are referred to as pharmaceuticals. The field encompasses drug composition, drug properties, interactions, Toxicology, and desirable effects that can be used in Therapy of diseases.

Development of medication is a vital concern to Medicine, but also has strong economical and political implications. To protect the consumer and prevent abuse, many governments regulate the manufacture, sale, and administration of medication. In the United States, the main regulatory body is the Food and Drug Administration through its publication of the USP.

Pharmacology as a science is practiced by pharmacologists. Studies can include theoretical pharmacology, in contrast to Clinical pharmacology, - the medical field of pharmacology.

Scientific background

A chemical has, from the pharmacological point-of-view, various properties. Pharmacokinetics is its fate (e.g. its Half-life and Volume of distribution) in the organism, and Pharmacodynamics is its mode of action and potential Toxicity.

When describing the pharmacokinetic properties of a chemical, a pharmacologist employs the ADME principle:

• Absorption - How is the medication absorbed (through the skin, the intestine, the oral mucosa)?
• Distribution - How does it spread through the organism?
• Metabolism - Is the medication converted chemically, and into which substances. Are these active? Could they be toxic?
• Excretion - How is the medication eliminated (through the bile, urine, skin)?

Medication is said to have a narrow or wide therapeutic margin or therapeutic window. Those with a narrow window are more difficult to dose and administer, and may require Therapeutic drug monitoring (examples are Warfarin, some antiepileptics, Aminoglycoside antibiotics).

Classification

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

For pain & consciousness (Anaesthetic drugs)

For musculo-skeletal disorders

 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

For the Respiratory system

For endocrine problems

For the reproductive system or Urinary system

For contraception

For Obstetrics and gynaecology

 gamolenic acid, gonadotropin release inhibitor, progestogen, dopamine agonist, oestrogen, Prostaglandin, gonadorelin, clomiphene, Tamoxifen, Diethylstilbestrol

For the Skin

For infections and infestations

For Immunology

For allergic disorders

For nutrition

For neoplastic disorders

For diagnostics

For euthanasia