Pharmacology comes from two Greek words "pharmakon" which illustrates medicine and "logos" which illustrates the study, it is simply combined to give a definition as a drug study. (Michael Adams, Norman Holland and Carol Urban, 2017). Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get Original Essay As of today, people have become more dependent on conventional medications without knowing the harm they might cause as they only give short-term relief. However, the study of drugs has a much broader perspective so, in the body of this essay, the discussion on the origins of drugs, their nature, their chemistry, effects, and along with their uses will be further broken down and elaborated. First of all, a drug is defined as any substance that influences the structure or functioning of a living organism. It is widely used for the prevention, diagnosis and treatment of diseases and for the relief of symptoms. (Oxford Dictionary of Nursing, 2014) Moving forward, since medications come in various forms and varieties, they also come from various sources discovered long ago by medical experts. Some of the major sources of drugs come from human, semi-synthetic, synthetic and natural sources. However, natural sources of drugs are further classified into specific categories such as animals, microorganisms, minerals, and plants. Furthermore, natural sources via plants are known to include roots, bark, leaves, and seeds; for example, aspirin, the drug used to treat fever, came from willow bark. Animal source is another source from which the drug is extracted and produced to treat diseases and test the susceptibility of bacteria and viruses. For example; The pig's pancreas delivers insulin to diabetic patients who can no longer produce insulin. The source of microorganisms may include some fungi, bacteria or molds that can produce important drugs, for example penicillin is a drug produced by the microorganism called penicillium notatum. And drugs obtained from minerals are those used to treat diseases and other serious illnesses as part of drug therapy. For example, the mineral ferrous sulfate (FeSo4) is used to treat an anemic patient who lacks iron. Likewise, a synthetic source is one where most drugs are produced in laboratories. These drugs can be produced in a much higher yield and are considered safe drugs, for example diphenoxylate is an antidiarrheal drug. As well as the semi-synthetic source that is obtained by altering the chemical structure of natural drugs, for example streptomycin is derived from penicillin. Furthermore, each drug is intended to have three special names; a chemical name, a generic or common name, and a trade or proprietary name. Firstly, the chemical name is assigned based on the chemical properties and composition of the drug, which also represents the nature of the drug, for example the chemical name of diazepam is 7-chloro-,3-dihydro-1-methyl-5 -phenyl-2H- 1,4-benzodiazepam-2-one. Secondly, the generic name, which is known to be a fixed name known throughout the world, is derived from the chemical name of the drug, but usually appears shorter and easier to remember. An example of a drug with its generic name would be aspirin. Third, the trade name of the drug provided by the company that produces it, for example, one of the trade names of diphenhydramine is called Benadryl. Furthermore, every drug that the body receives through several administrations is destined to be absorbed by the body. Therefore, it is known that absorption is a phase in which substances begin tomove, from the site of administration, across the body's membranes and into body fluids where it can be transported throughout the body. It is the first factor that represents the time taken for the drug to show effects in pharmacokinetics. However, absorption has some factors that interfere with its working process such as the formulation and dose of the drug. This is when, for example, the type of drug determines the speed of its absorption property; Liquid medications have faster absorption properties than capsules. Secondly, the dosage, which absorption is believed to occur mostly when the dosages of the drug are high, creating a rapid effect compared to that administered at low dosages. Third, the route of administration whereby drugs administered intravenously have faster absorption as they are administered directly into the bloodstream. The size of the drug molecule is another factor that influences absorption, when some drug molecules appear larger in size they tend to delay absorption by the body compared to smaller molecules. Furthermore, the surface area of ​​the adsorption site influences the adsorption where the size is larger. surface, the faster the drug is absorbed. Another is blood flow, which is when blood flow at the site of administration causes faster absorption and ultimately lipid solubility of the drug. Because fat-soluble drugs are absorbed faster, soluble drugs are not. Furthermore, drug administration is the means and ways in which drugs are administered to treat illnesses and diseases, so there are eleven possible ways of administering them to clients. Intravenous, intramuscular, intranasal, transdermal, rectal, vaginal, parenteral, intradermal, nebulizer and inhaler, and topical administration. (Galbraith. A, Bullock. S, Manias. E, 2004) For starters, drugs administered intravenously are known to have a rapid effect as the drug is infused directly into the bloodstream. Furthermore, in case of rapid changes in adverse reactions, the procedure can be stopped before the blood level is altered. An example of a medication administered intravenously is the antibiotic cloxacillin, which is diluted in the intravenous chamber and administered to the client. Intramuscular administration is the injection administered to specific muscles due to good blood supply. This allows for a much faster rate of absorption, for example penicillin is administered via intramuscular injection. Intranasal administration helps relieve nasal congestion during colds, however, there are some medications that are administered intranasally such as vasopressin. Due to the mucosa present in the nasal cavity absorption occurs. In addition, transdermal administration occurs when the epidermal layer of the body is used to administer drugs, so the advantage of such administration is that drugs can avoid the first pass effect in the liver and pass digestive enzymes. A drug that is administered transdermally may be nicotine which helps a person quit smoking. The rectal route is another way of administering medications and is known to be the safest way of administering medications. Despite its slow absorption, it can be very reliable and the first pass effect is avoided. Additionally, vaginal administration that normally treats vaginal pain and infections are inserted as creams. However, any drug that avoids the gastrointestinal tract can be called parenteral administration. This type of administration is much more prone to agent entry.