Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
patch test
Table of Contents
Introduction References & Edit History Related Topics
Related Questions
Read Next
Macro Aedes aegypti Mosquito. Close up a Mosquito sucking human blood,
Why Do Mosquito Bites Itch?
Aspirin pills.
7 Drugs that Changed the World
Photo of the antacid Tums
How Do Antacids Work?
Blackboard inscribed with scientific formulas and calculations in physics and mathematics
The World Science Festival’s Pioneers in Science
People wearing surgical masks (also called face mask or medical masks or safety masks) walk through the city center of Milan, Italy on Feb. 23, 2020. Coronavirus disease COVID-19 pandemic
How Do Face Masks Control the Spread of Disease?
Discover
Ahura Mazda - relief of the Zoroastrian god Ahura Mazda at the ancient ruins of Persepolis in Iran. Also known as Ormazd Zoroastrianism,
Which Religion Is the Oldest?
A mug shot taken by the regional Colombia control agency in Medellin
Pablo Escobar: 8 Interesting Facts About the King of Cocaine
Stylish light blue jeans on wooden background, closeup of inset pocket
Why Do Jeans Have That Tiny Pocket?
Fish. Lionfish. Lion-fish. Turkey fish. Fire-fish. Red lionfish. Pterois volitans. Venomous fin spines. Coral reefs. Underwater. Ocean. Red lionfish swims by seaweed.
10 of the World’s Most Dangerous Fish
Close-up of ostriches (Struthio camelus) necks and heads; location unknown.
6 of the World's Most Dangerous Birds
Facsimile of one of William Henry Ireland's forgeries, a primitive self-portrait of William Shakespeare(tinted engraving). Published for Samuel Ireland, Norfolk Street, Strand, December 1, 1795. (W.H. Ireland, forgery)
The Time a Law Clerk Successfully Forged a New Shakespeare Play to Impress His Dad
Ice Sledge Hockey, Hockey Canada Cup, USA (left) vs Canada, 2009. UBC Thunderbird Arena, Vancouver, BC, competition site for Olympic ice hockey and Paralympic ice sledge hockey. Vancouver 2010 Olympic and Paralympic Winter Games, Vancouver Olympics
10 Best Hockey Players of All Time

patch test

medicine
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Share
Share to social media
URL
https://mainten.top/science/patch-test
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

External Websites
Written and fact-checked by
The Editors of Encyclopaedia Britannica
Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.
The Editors of Encyclopaedia Britannica
Article History
Related Topics:
allergy
skin test
See all related content

patch test, controlled application of biological or chemical substances to the skin in order to detect if the subject has an allergic hypersensitivity to one of them. The test was originally developed to test new chemical compounds for their allergic potential on animals but has since become widely used to diagnose allergies in humans. Patch testing is usually done on the skin of the upper back or the outer arm. Small amounts of test substances diluted in a solvent such as water or petroleum jelly are applied to the skin under a patch of cloth or soft paper and an impermeable membrane. The patch is left in place for 48 hours, after which the skin reaction is examined and scored from 0 (no apparent reaction) to 4+, indicating severe blistering as well as angry redness of the exposed skin. Patch testing is an extremely accurate indicator of allergic sensitivity.