Editing Route of administration (section)

===By application location===
====Enteral/gastrointestinal route====
Through the [[gastrointestinal tract]] is sometimes termed ''enteral or enteric administration'' (literally meaning 'through the [[intestines]]'). ''Enteral/enteric administration'' usually includes ''[[oral administration|oral]]''<ref name="url195_20-1-3.1.htm"/> (through the [[Human mouth|mouth]]) and ''[[Rectal (medicine)|rectal]]'' (into the [[rectum]])<ref name="url195_20-1-3.1.htm">{{cite web |url=http://www.oar.state.ok.us/viewhtml/195_20-1-3.1.htm |title=Oklahoma Administrative Code and Register > 195:20-1-3.1. Pediatric conscious sedation utilizing enteral methods (oral, rectal, sublingual) |access-date=2009-01-18 |archive-url=https://web.archive.org/web/20110722120920/http://www.oar.state.ok.us/viewhtml/195_20-1-3.1.htm |archive-date=2011-07-22 |url-status=live }}</ref> administration, in the sense that these are taken up by the intestines. However, uptake of drugs administered orally may also occur already in the [[stomach]], and as such ''gastrointestinal'' (along the [[gastrointestinal tract]]) may be a more fitting term for this route of administration. Furthermore, some application locations often classified as ''enteral'', such as [[sublingual administration|sublingual]]<ref name="url195_20-1-3.1.htm"/> (under the tongue) and [[sublabial administration|sublabial]] or [[Buccal administration|buccal]] (between the cheek and gums/[[gingiva]]), are taken up in the proximal part of the [[gastrointestinal tract]] without reaching the intestines. Strictly [[enteral administration]] (directly into the intestines) can be used for systemic administration, as well as local (sometimes termed [[topical]]), such as in a contrast [[enema]], whereby contrast media are infused into the intestines for imaging. However, for the purposes of classification based on location of effects, the term enteral is reserved for substances with systemic effects.

[[File:Administering medication into a gastric tube.jpg|thumb|A medical professional injects medication into a gastric tube.]]
Many drugs as [[Tablet (pharmacy)|tablets]], [[Capsule (pharmacy)|capsules]], or drops are taken orally. Administration methods directly into the stomach include those by [[gastric feeding tube]] or [[gastrostomy]]. Substances may also be placed into the [[small intestine]]s, as with a [[duodenal]] feeding tube and [[enteral administration|enteral nutrition]]. Enteric coated tablets are designed to dissolve in the intestine, not the stomach, because the drug present in the tablet causes irritation in the stomach.
[[File:Administering-med-rectally-2.png|thumb|Administering medication rectally]]
The [[rectal]] route is an effective route of administration for many medications, especially those used at the [[end-of-life care|end of life]].<ref>{{cite journal |vauthors=Davis MP, Walsh D, LeGrand SB, Naughton M | year = 2002 | title = Symptom control in cancer patients: the clinical pharmacology and therapeutic role of suppositories and rectal suspensions | journal = Support Care Cancer | volume = 10 | issue = 2| pages = 117–38 | doi=10.1007/s00520-001-0311-6| pmid = 11862502 | s2cid = 30569818 }}</ref><ref>{{cite journal |vauthors=De Boer AG, Moolenaar F, de Leede LG, Breimer DD | year = 1982 | title = Rectal drug administration: clinical pharmacokinetic considerations | journal = Clin Pharmacokinetics | volume = 7 | issue = 4| pages = 285–311 | doi=10.2165/00003088-198207040-00002 | pmid=6126289| s2cid = 41562861 }}</ref><ref>{{cite journal |vauthors=Van Hoogdalem EJ, de Boer AG, Breimer DD | year = 1991 | title = Pharmacokinetics of rectal drug administration, Part 1 | journal = Clin Pharmacokinet | volume = 21 | issue = 1| pages = 11–26 | doi=10.2165/00003088-199121010-00002| pmid = 1717195 | s2cid = 35104089 }}</ref><ref>{{cite journal |vauthors=Van Hoogdalem EJ, de Boer AG, Breimer DD | year = 1991 | title = Pharmacokinetics of rectal drug administration, Part 2 | journal = Clin Pharmacokinet | volume = 21 | issue = 2| pages = 110–128 | doi=10.2165/00003088-199121020-00003 | pmid = 1884566| s2cid = 11720029 }}</ref><ref>{{cite journal |vauthors=Moolenaar F, Koning B, Huizinga T | year = 1979 | title = Biopharmaceutics of rectal administration of drugs in man. Absorption rate and bioavailability of phenobarbital and its sodium salt from rectal dosage forms | journal = [[International Journal of Pharmaceutics]] | volume = 4 | issue = 2| pages = 99–109 | doi=10.1016/0378-5173(79)90057-7}}</ref><ref>{{cite journal |vauthors=Graves NM, Holmes GB, Kriel RL, Jones-Saete C, Ong B, Ehresman DJ | year = 1989 | title = Relative bioavailability of rectally administered phenobarbital sodium parenteral solution | journal = DICP: The Annals of Pharmacotherapy | volume = 23 | issue = 7–8| pages = 565–568 | doi=10.1177/1060028089023007-806| pmid = 2763578 | s2cid = 27397387 }}</ref><ref>{{cite journal |vauthors=Moolenaar S, Bakker S, Visser J, Huizinga T | year = 1980 | title = Biopharmaceutics of rectal administration of drugs in man IX. Comparative biopharmaceutics of diazepam after single rectal, oral, intramuscular and intravenous administration in man | journal = International Journal of Pharmaceutics | volume = 5 | issue = 2| pages = 127–137 | doi=10.1016/0378-5173(80)90017-4}}</ref> The walls of the rectum absorb many medications quickly and effectively.<ref>[http://www.hpna.org.] {{webarchive|url=https://web.archive.org/web/20130126195447/http://www.hpna.org/|date=2013-01-26}} Nee, Douglas, Pharm D, MS. "Rectal Administration of Medications at the End of Life". HPNA Teleconference, December 6, 2006, accessed November 2013.</ref> Medications delivered to the distal one-third of the rectum at least partially avoid the "[[first pass effect]]" through the liver, which allows for greater [[bio-availability]] of many medications than that of the oral route. Rectal [[mucosa]] is highly [[vascularized]] tissue that allows for rapid and effective absorption of medications.<ref>{{cite web|url=http://www.eperc.mcw.edu/EPERC/FastFactsIndex/ff_257.htm|title=Use of Rectal Meds for Palliative Care Patients. End of Life / Palliative Education Resource Center, Medical College of Wisconsin|website=mcw.edu|access-date=14 April 2018|url-status=dead|archive-url=https://web.archive.org/web/20140602060038/http://www.eperc.mcw.edu/EPERC/FastFactsIndex/ff_257.htm|archive-date=2 June 2014}}</ref> A [[suppository]] is a solid [[dosage form]] that fits for [[rectal administration]]. In [[hospice care]], a specialized rectal [[Macy Catheter|catheter]], designed to provide comfortable and discreet administration of ongoing medications provides a practical way to deliver and retain liquid formulations in the [[distal]] rectum, giving health practitioners a way to leverage the established benefits of rectal administration. The [[Murphy drip]] is an example of rectal infusion.

====Parenteral route====
[[File:Needle-insertion-angles-1.png|thumb|Needle insertion angles for 4 types of parenteral administration of medication: intramuscular, subcutaneous, intravenous, and intradermal injection.]]
The parenteral route is any route that is not [[Enteral administration|enteral]] (''[[wikt:para-#Etymology 1|par-]]'' + ''enteral'').

Parenteral administration can be performed by [[Injection (medicine)|injection]], that is, using a needle (usually a [[hypodermic needle]]) and a [[syringe]],<ref>{{cite web|url=http://dictionary.cambridge.org/dictionary/english/injection|title=injection|website=Cambridge dictionary|access-date=2017-07-30|archive-url=https://web.archive.org/web/20170730202011/http://dictionary.cambridge.org/dictionary/english/injection|archive-date=2017-07-30|url-status=live}}</ref> or by the insertion of an [[indwelling catheter]].

Locations of application of parenteral administration include:
* Central nervous system:
:* [[Epidural]] (synonym: peridural) (injection or infusion into the [[epidural space]]), e.g. epidural anesthesia.
:* Intracerebral (into the cerebrum) administration by direct injection into the brain. Used in experimental research of chemicals<ref>{{cite web |url=http://www.neurotransmitter.net/mdmametabolites.html |title=MDMA (ecstasy) metabolites and neurotoxicity: No occurrence of MDMA neurotoxicity from metabolites when injected directly into brain, study shows |publisher=Neurotransmitter.net |access-date=2010-08-19 |archive-url=https://web.archive.org/web/20100807215102/http://www.neurotransmitter.net/mdmametabolites.html |archive-date=2010-08-07 |url-status=live }}</ref> and as a treatment for malignancies of the brain.<ref>{{cite journal|title=A potential application for the intracerebral injection of drugs entrapped within liposomes in the treatment of human cerebral gliomas  |date=2010-07-06 |pmc=1028604|last2=Firth|first2=G|last3=Oliver|first3=S|last4=Uttley|first4=D|last5=O'Laoire|first5=S|volume=48|issue=12|pages=1213–1219|journal=Journal of Neurology, Neurosurgery, and Psychiatry|doi=10.1136/jnnp.48.12.1213|pmid=2418156|author=McKeran RO, Firth G, Oliver S, Uttley D, O'Laoire S}}</ref> The intracerebral route can also interrupt the blood brain barrier from holding up against subsequent routes.<ref>{{cite journal|title=Blood–brain barrier changes following intracerebral injection of human recombinant tumor necrosis factor-α in the rat |doi=10.1007/BF01057957 |volume=20 |journal=Journal of Neuro-Oncology |pages=17–25 |year=1994 |author=Wright JL, Merchant RE|issue=1 |pmid=7807180 |s2cid=12445653 }}</ref>
:* [[intracerebroventricular injection|Intracerebroventricular]] (into the cerebral ventricles) administration into the ventricular system of the brain. One use is as a last line of opioid treatment for terminal cancer patients with intractable [[cancer pain]].<ref>{{cite journal |url=http://www.anesthesia-analgesia.org/cgi/content/full/89/5/1209 |title=Acute Decreases in Cerebrospinal Fluid Glutathione Levels after Intracerebroventricular Morphine for Cancer Pain |publisher=Anesthesia-analgesia.org |date=1999-06-22 |doi=10.1213/00000539-199911000-00023 |access-date=2010-08-19 |archive-url=https://web.archive.org/web/20060106043224/http://www.anesthesia-analgesia.org/cgi/content/full/89/5/1209 |archive-date=2006-01-06 |url-status=live |last1=Goudas |first1=Leonidas C. |last2=Langlade |first2=Agnes |last3=Serrie |first3=Alain |last4=Matson |first4=Wayne |last5=Milbury |first5=Paul |last6=Thurel |first6=Claude |last7=Sandouk |first7=Pierre |last8=Carr |first8=Daniel B. |journal=Anesthesia & Analgesia |volume=89 |issue=5 |pages=1209–1215 }}</ref>

[[File:Applying transdermal patch.jpg|thumb|A transdermal patch which delivers medication is applied to the skin. The patch is labelled with the time and date of administration as well as the administrator's initials.]]
[[File:Instilling nasal medication.jpg|thumb|A medical professional applies nose drops.]]
* Epicutaneous (application onto the skin). It can be used both for local effect as in allergy testing and typical [[local anesthesia]], as well as [[:wikt:systemic|systemic]] effects when the active substance diffuses through skin in a [[transdermal]] route.
*{{Anchor|buccal}}Sublingual and buccal medication administration is a way of giving someone medicine orally (by mouth). [[Sublingual administration]] is when medication is placed under the tongue to be absorbed by the body. The word "sublingual" means "under the tongue." Buccal administration involves placement of the drug between the gums and the cheek. These medications can come in the form of tablets, films, or sprays. Many drugs are designed for sublingual administration, including cardiovascular drugs, steroids, barbiturates, opioid analgesics with poor gastrointestinal bioavailability, enzymes and, increasingly, vitamins and minerals.
* [[Extra-amniotic administration]], between the [[endometrium]] and [[fetal membranes]].
* [[Nasal administration]] (through the nose) can be used for topically acting substances, as well as for [[Insufflation (medicine)|insufflation]] of e.g. [[decongestant]] nasal sprays to be taken up along the [[respiratory tract]]. Such substances are also called ''inhalational'', e.g. [[inhalational anesthetics]].
* Intra-arterial (into an [[artery]]), e.g. [[vasodilator]] drugs in the treatment of [[vasospasm]] and [[thrombolytic drug]]s for treatment of [[embolism]].
* Intra-[[joint|articular]], into a joint space. It is generally performed by [[joint injection]]. It is mainly used for symptomatic relief in [[osteoarthritis]].
* [[Intracardiac]] (into the heart), e.g. [[adrenaline]] during [[cardiopulmonary resuscitation]] (no longer commonly performed).
* [[Intracavernous injection]], an injection into the base of the [[penis]].
* [[Intradermal]], (into the skin itself) is used for [[Skin allergy test|skin testing]] some [[allergens]], and also for [[mantoux test]] for [[tuberculosis]].
* Intralesional (into a skin lesion), is used for local skin lesions, e.g. acne medication.
* [[Intramuscular injection|Intramuscular]] (into a [[muscle]]), e.g. many [[vaccine]]s, antibiotics, and long-term psychoactive agents. Recreationally the colloquial term 'muscling' is used.<ref name="Fenway Community Health">{{cite web|url=http://www.fenwayhealth.org/site/PageServer?pagename=CM_efc_effects |website=Fenway Community Health|title = Crystal Meth: The Effects |publisher=[[Fenway Health]] |url-status = dead|archive-url = https://web.archive.org/web/20101210183228/http://www.fenwayhealth.org/site/PageServer?pagename=CM_efc_effects|archive-date = 10 December 2010}}</ref>
[[File:Instilling eye medication.jpg|thumb|Topical ocular administration]]
* Intraocular, into the eye, e.g., some medications for [[glaucoma]] or [[eye neoplasm]]s.
* [[Intraosseous infusion]] (into the [[bone]] marrow) is, in effect, an indirect intravenous access because the bone marrow drains directly into the venous system. This route is occasionally used for drugs and fluids in emergency medicine and pediatrics when intravenous access is difficult.
* [[intraperitoneal injection|Intraperitoneal]], (infusion or injection into the [[peritoneum]]) e.g. [[peritoneal dialysis]].
* [[Intrathecal]] (into the spinal canal) is most commonly used for spinal [[anesthesia]] and [[chemotherapy]].
* Intrauterine.
* [[Intravaginal administration]], in the [[vagina]].
* [[intravenous therapy|Intravenous]] (into a [[vein]]), e.g. many drugs, [[Parenteral nutrition|total parenteral nutrition]].
* [[Intravesical drug delivery|Intravesical]] infusion is into the urinary bladder.
* [[Intravitreal]], through the eye.
* Subcutaneous (under the skin).<ref>{{cite book|last=Malenka|first=Eric J. Nestler, Steven E. Hyman, Robert C.|title=Molecular Neuropharmacology: A Foundation for Clinical Neuroscience|year=2009|publisher=McGraw-Hill Medical|location=New York|isbn=978-0-07-148127-4|edition=2nd}}</ref> This generally takes the form of [[subcutaneous injection]], e.g. with [[insulin]]. [[Skin popping]] is a slang term that includes subcutaneous injection, and is usually used in association with [[recreational drugs]]. In addition to injection, it is also possible to slowly infuse fluids subcutaneously in the form of [[hypodermoclysis]].
* [[transdermal technology|Transdermal]] (diffusion through the intact skin for systemic rather than topical distribution), e.g. [[transdermal patch]]es such as [[fentanyl]] in pain therapy, [[nicotine]] patches for treatment of [[Substance use disorder|addiction]] and [[Glyceryl trinitrate (pharmacology)|nitroglycerine]] for treatment of [[angina pectoris]].
* [[Perivascular administration]] (perivascular medical devices and perivascular drug delivery systems are conceived for local application around a blood vessel during open vascular surgery).<ref>{{cite journal | author = Mylonaki I, Allémann É, Saucy F, Haefliger J-A, Delie F, Jordan O | year = 2017 | title = Perivascular medical devices and drug delivery systems: Making the right choices | url = https://archive-ouverte.unige.ch/unige:92897 | journal = Biomaterials | volume = 128 | pages = 56–68 | doi = 10.1016/j.biomaterials.2017.02.028 | pmid = 28288349 | access-date = 2020-03-23 | archive-date = 2020-04-23 | archive-url = https://web.archive.org/web/20200423234047/https://archive-ouverte.unige.ch/unige:92897 | url-status = live }}</ref>
* Transmucosal (diffusion through a mucous membrane), e.g. [[Insufflation (medicine)|insufflation]] (snorting) of [[cocaine]], [[sublingual]], i.e. under the tongue, [[Sublabial route of administration|sublabial]], i.e. between the lips and [[gingiva]], and oral spray or vaginal suppository for  [[nitroglycerine]].