Editing Pseudoephedrine (section)

====Elimination====
Pseudoephedrine is [[excretion|excreted]] primarily via the [[kidney]]s in [[urine]].<ref name="GłowackaWiela-Hojeńska2021" /><ref name="ChuaBenrimojTriggs1989" /> Its urinary excretion is highly influenced by urinary [[pH]] and is increased when the urine is [[acidic]] and is decreased when it is [[alkaline]].<ref name="GłowackaWiela-Hojeńska2021" /><ref name="ChuaBenrimojTriggs1989" /><ref name="HughesEmpeyLand1983" />

The [[elimination half-life]] of pseudoephedrine on average is 5.4{{nbsp}}hours<ref name="Eccles2007" /> and ranges from 3 to 16{{nbsp}}hours depending on urinary pH.<ref name="GłowackaWiela-Hojeńska2021" /><ref name="ChuaBenrimojTriggs1989" /> At a pH of 5.6 to 6.0, the [[elimination half-life]] of pseudoephedrine was 5.2 to 8.0{{nbsp}}hours.<ref name="ChuaBenrimojTriggs1989" /> In one study, a more acidic pH of 5.0 resulted in a half-life of 3.0 to 6.4{{nbsp}}hours, whereas a more alkaline pH of 8.0 resulted in a half-life of 9.2 to 16.0{{nbsp}}hours.<ref name="ChuaBenrimojTriggs1989" /> Substances that influence urinary acidity and are known to affect the excretion of amphetamine derivatives include [[acidifier|urinary acidifying agents]] like [[ascorbic acid]] and [[ammonium chloride]] as well as [[alkalinizing agent|urinary alkalinizing agents]] like [[acetazolamide]].<ref name="PatrickMarkowitz1997"/>

A majority of an [[oral administration|oral]] dose of pseudoephedrine is excreted unchanged in urine within 24{{nbsp}}hours of administration.<ref name="ChuaBenrimojTriggs1989" /> This has been found to range from 43 to 96%.<ref name="GłowackaWiela-Hojeńska2021" /><ref name="ChuaBenrimojTriggs1989" /><ref name="Eccles2007" /> The amount excreted unchanged is dependent on urinary pH similarly to the drug's half-life, as a longer half-life and duration in the body allows more time for the drug to be metabolized.<ref name="ChuaBenrimojTriggs1989" />

The [[duration of action]] of pseudoephedrine, which is dependent on its [[elimination (pharmacology)|elimination]], is 4 to 12{{nbsp}}hours.<ref name="GłowackaWiela-Hojeńska2021" /><ref name="Aaron1990" />

Pseudoephedrine has been reported to accumulate in people with [[renal impairment]].<ref name="Sequeira1998">{{cite book | vauthors = Sequeira RP N| title=Side Effects of Drugs Annual | chapter=Central nervous system stimulants and drugs that suppress appetite | publisher=Elsevier | volume=21 | date=1998 | isbn=978-0-444-82818-7 | doi=10.1016/s0378-6080(98)80005-6 | pages=1–8}}</ref><ref name="SicaComstock1989">{{cite journal | vauthors = Sica DA, Comstock TJ | title = Pseudoephedrine accumulation in renal failure | journal = Am J Med Sci | volume = 298 | issue = 4 | pages = 261–263 | date = October 1989 | pmid = 2801760 | doi = 10.1097/00000441-198910000-00010 | url = }}</ref><ref name="LyonTurney1996">{{cite journal | vauthors = Lyon CC, Turney JH | title = Pseudoephedrine toxicity in renal failure | journal = Br J Clin Pract | volume = 50 | issue = 7 | pages = 396–397 | date = 1996 | pmid = 9015914 | doi = 10.1111/j.1742-1241.1996.tb09584.x| url = }}</ref>