Editing Pharmacology (section)

===Pharmacokinetics===
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[[Pharmacokinetics]] is the study of the bodily absorption, distribution, metabolism, and excretion of drugs.<ref>{{cite web |url= https://www.merriam-webster.com/dictionary/pharmacokinetics |title= Pharmacokinetics |website= Merriam-Webster |access-date= July 16, 2019 |archive-date= 16 July 2019 |archive-url= https://web.archive.org/web/20190716151748/https://www.merriam-webster.com/dictionary/pharmacokinetics |url-status= live }}</ref>

When describing the pharmacokinetic properties of the chemical that is the active ingredient or [[Active ingredient|active pharmaceutical ingredient]] (API), pharmacologists are often interested in ''L-ADME'':
* [[Liberation (pharmacology)|Liberation]] – How is the API disintegrated (for solid oral forms (breaking down into smaller particles), dispersed, or dissolved from the medication?
* [[Absorption (digestive)|Absorption]] – How is the API absorbed (through the [[human skin|skin]], the [[intestine]], the [[oral mucosa]])?
* [[Distribution (pharmacology)|Distribution]] – How does the API spread through the organism?
* [[Drug metabolism|Metabolism]] – Is the API converted chemically inside the body, and into which substances. Are these active (as well)? Could they be toxic?
* [[Excretion]] – How is the API excreted (through the bile, urine, breath, skin)?

[[Drug metabolism]] is assessed in pharmacokinetics and is important in drug research and prescribing.

Pharmacokinetics is the movement of the drug in the body, it is usually described as 'what the body does to the drug' the physico-chemical properties of a drug will affect the rate and extent of absorption, extent of distribution, metabolism and elimination. The drug needs to have the appropriate molecular weight, polarity etc. in order to be absorbed, the fraction of a drug that reaches the systemic circulation is termed bioavailability, this is simply a ratio of the peak plasma drug levels after oral administration and the drug concentration after an IV administration (first pass effect is avoided and therefore no amount drug is lost). A drug must be lipophilic (lipid soluble) in order to pass through biological membranes because biological membranes are made up of a lipid bilayer (phospholipids etc.). Once the drug reaches the blood circulation it is then distributed throughout the body and being more concentrated in highly perfused organs.