Editing Intraocular pressure (section)

==Influencing factors==
=== Daily variation ===
Intraocular pressure varies throughout the night and day. The diurnal variation for normal eyes is between 3 and 6 [[mmHg]] and the variation may increase in glaucomatous eyes. During the night, intraocular pressure may not decrease<ref name="pmid21330554">{{cite journal |vauthors = Liu JH, Weinreb RN |title = Monitoring intraocular pressure for 24 h |journal = Br J Ophthalmol |volume = 95 |issue = 5 |pages = 599–600 |date = May 2011 |pmid = 21330554 |doi = 10.1136/bjo.2010.199737  |s2cid = 42736853 }}</ref> despite the slower production of aqueous humour.<ref>{{cite journal |last=Brubaker RF |title=Flow of aqueous humor in humans |journal=Invest Ophthalmol Vis Sci |year=1991 |volume=32 |issue=13 |pages=3145–3166 |pmid=1748546}}</ref>   [[Glaucoma]] patients' 24-hour IOP profiles may differ from those of healthy individuals.<ref name="pmid12657596">{{cite journal |vauthors = Liu JH, Zhang X, Kripke DF, Weinreb RN |title = Twenty-four-hour intraocular pressure pattern associated with early glaucomatous changes |journal = Invest. Ophthalmol. Vis. Sci. |volume = 44 |issue = 4 |pages = 1586–90 |date = April 2003 |pmid = 12657596 |doi = 10.1167/iovs.02-0666 |issn=1552-5783 |doi-access = }}</ref>

=== Fitness and exercise ===
There is some inconclusive research that indicates that exercise could possibly affect IOP (some positively and some negatively).<ref>Studies have also been conducted on both healthy and sedentary individuals to determine if intraocular pressure could be reduced with other types of exercise. Some forms of exertion have been found to result in a decrease in intraocular pressure. Exercises studied included; walking, jogging, and running. [http://journals.tubitak.gov.tr/medical/issues/sag-00-30-2/sag-30-2-20-9907-19.pdf Acute Dynamic Exercise Reduces Intraocular Pressure] {{Webarchive|url=https://web.archive.org/web/20110928075707/http://journals.tubitak.gov.tr/medical/issues/sag-00-30-2/sag-30-2-20-9907-19.pdf |date=28 September 2011 }}, Departments of Ophthalmology, Physiology, Faculty of Medicine, Atatürk University, Erzurum- Turkey. July 1999.</ref><ref>[http://informahealthcare.com/doi/abs/10.1080/03014469500004202 Qureshi IA. Effects of mild, moderate and severe exercise on intraocular pressure of sedentary subjects. Rawalpindi Medical College, Rawalpindi, Pakistan]</ref><ref name="Vieira" />

=== Musical instruments ===
Playing some musical wind instruments has been linked to increases in intraocular pressure.  A 2011 study focused on brass and woodwind instruments observed "temporary and sometimes dramatic elevations and fluctuations in IOP".<ref name="pmid21234587">{{cite journal | vauthors = Schmidtmann G, Jahnke S, Seidel EJ, Sickenberger W, Grein HJ | title = Intraocular pressure fluctuations in professional brass and woodwind musicians during common playing conditions | journal = Graefes Arch. Clin. Exp. Ophthalmol. | volume = 249 | issue = 6 | pages = 895–901 | date = June 2011 | pmid = 21234587 | doi = 10.1007/s00417-010-1600-x | url = https://pearl.plymouth.ac.uk/bitstream/10026.1/10195/1/Schmidtmann_2011.pdf | hdl = 10026.1/10195 | s2cid = 21452109 | hdl-access = free | access-date = 24 September 2019 | archive-date = 11 January 2022 | archive-url = https://web.archive.org/web/20220111155744/https://pearl.plymouth.ac.uk/bitstream/handle/10026.1/10195/Schmidtmann_2011.pdf;jsessionid=C5A3CBDA079355BE3F54DAFDFC2C8B64?sequence=1 | url-status = dead }}</ref>
Another study found that the magnitude of increase in intraocular pressure correlates with the intraoral resistance associated with the instrument, and linked intermittent elevation of intraocular pressure from playing high-resistance wind instruments to incidence of visual field loss.<ref name="pmid10647731">{{cite journal | vauthors = Schuman JS, Massicotte EC, Connolly S, Hertzmark E, Mukherji B, Kunen MZ | title = Increased intraocular pressure and visual field defects in high resistance wind instrument players | journal = Ophthalmology | volume = 107 | issue = 1 | pages = 127–33 | date = January 2000 | pmid = 10647731 | doi = 10.1016/s0161-6420(99)00015-9 }}</ref>
The range of intraoral pressure involved in various classes of ethnic wind instruments, such as [[Native American flute]]s, has been shown to be generally lower than Western classical wind instruments.<ref name="IOP_Ethnic">
{{cite journal
 | title = Intraoral Pressure in Ethnic Wind Instruments
 | author = Clinton F. Goss
 | date=August 2013
 | url = http://www.Flutopedia.com/refs/Goss_2013_IntraoralPressureInEthnicWindInstruments.pdf
 | journal=Flutopedia
 | access-date = 22 August 2013
 | bibcode = 2013arXiv1308.5214G
 | arxiv=1308.5214
}}
</ref>

=== Drugs ===
Intraocular pressure also varies with a number of other factors such as [[heart]] rate, [[Respiration (physiology)|respiration]], fluid intake, systemic medication and topical drugs. [[Ethanol|Alcohol]] and [[Cannabis (drug)|marijuana]] consumption leads to a transient decrease in intraocular pressure and [[caffeine]] may increase intraocular pressure.<ref>Intraocular pressure measure on normal eyes by Pardianto G et al., in Mimbar Ilmiah Oftalmologi Indonesia.2005;2:78-9.</ref>

Taken orally, [[glycerol]] (often mixed with fruit juice to reduce its sweet taste) can cause a rapid, temporary decrease in intraocular pressure.  This can be a useful initial emergency treatment of severely elevated pressure.<ref name="pmid14184494">{{cite journal | vauthors = Drance SM | title = Effect of Oral Glycerol on Intraocular Pressure in Normal and Glaucomatous Eyes | journal = Arch. Ophthalmol. | volume = 72 | issue = 4| pages = 491–3 | date = October 1964 | pmid = 14184494 | doi = 10.1001/archopht.1964.00970020491009 }}</ref>

The depolarising muscle relaxant [[succinylcholine]], which is used in [[anaesthesia]], transiently increases IOP by around 10&nbsp;mmHg for a few minutes.  This is significant for example if the patient requires anaesthesia for a [[trauma (medicine)|trauma]] and has sustained an eye (globe) perforation.  The mechanism is not clear but it is thought to involve contraction of tonic [[myofibrils]] and transient dilation of [[choroidal]] blood vessels.  [[Ketamine]] also increases IOP.<ref>{{cite book|vauthors = Brunton L, Chabner BA, Knollman B|title=Goodman & Gilman's: The Pharmacological Basis of Therapeutics|chapter=19. General Anesthetics and Therapeutic Gases|publisher=The McGraw-Hill Companies, Inc.|isbn=978-0-07-162442-8|date=2011|edition=12th|location=New York, USA|page=539}}</ref><ref>{{Cite web |title=Ocular Therapeutix Inc (OCUL) |url=https://biotickr.com/biotech-stocks/united-states-of-america/ocul-ocular-therapeutix-inc |access-date=2022-09-13 |website=biotickr |language=en}}</ref>