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Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

Registrationplugin-autotooltip__plain plugin-autotooltip_bigRegistration

At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

After you've registered, you'll be able to login with your password at any time…

How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

Like most Wikis, the site doesn't use

Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax? A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual …

Newsplugin-autotooltip__plain plugin-autotooltip_bigNews

[ newest at the top ]

• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn th…

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Legalplugin-autotooltip__plain plugin-autotooltip_bigLegal

Content in general

Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…


538 unknowns listed

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Ketamine (treatment for depression)

The use of Ketamine to treat depression was formally investigated in a 2006 report for JAMA Psychiatry. A team based at the US National Institute of Mental Health (NIMH) in Bethesda, Maryland, found that :

“Robust and rapid antidepressant effects resulted from a single intravenous dose of an N-methyl-D-aspartate antagonist; onset occurred within 2 hours postinfusion and continued to remain significant for 1 week.”
“To our knowledge, there has never been a report of any other drug or somatic treatment (ie, sleep deprivation, thyrotropin-releasing hormone, antidepressant, dexamethasone, or electroconvulsive therapy) that results in such a dramatic rapid and prolonged response with a single administration.”

The mechanism of its action, however, is still unclear.

A new (2017) study, covered in Nature suggests that a previous theory (that it inhibits the brain's NMDA-receptors) may be incorrect.

“Their finding adds to recent studies contradicting a long-held idea that the drug works mainly by blocking proteins called NMDA receptors, on the surface of brain cells, which transmit signals between those cells.”

Note that a third (also as yet unproven) theory instead suggests that breakdown chemicals of the drug - rather than the drug itself - may be responsible for its anti-depressant effects.

Note: The 'enantiomer' (i.e. mirror image molecule) of Ketamine is called Esketamine (marketed under the name Ketanest and others) it has similar properties, and is also used to treat depression - also by an unknown mechanism.

Update Oct 2018 : “Johnson & Johnson has submitted its esketamine for regulatory approval, but researchers still don't understand how the fast-acting antidepressant lifts moods.” Nature Reviews Drug Discovery volume 17, pages 773–775


Also see: Lithiumplugin-autotooltip__plain plugin-autotooltip_bigLithium (treatment for bipolar disorder)

Lithium, normally in the form of lithium carbonate (Li2CO3) is widely recognised as the 'gold standard' prescribed drug for treating bipolar disorder, depression and mania.

In widespread use since the early 1970s, lithium carb…
and Major Depressive Disorderplugin-autotooltip__plain plugin-autotooltip_bigMajor Depressive Disorder

Major depressive disorder (MDD), also known simply as depression, is a mental disorder characterized by at least two weeks of pervasive low mood.

Current estimates are that severe depression affects around 2% of the global population at any g…
and General Anaestheticsplugin-autotooltip__plain plugin-autotooltip_bigGeneral Anaesthetics

A general anaesthetic is a drug that brings about a reversible loss of consciousness. In formal use since 1842 - with the first public demonstration of ether to carry out surgery. (Though it's likely that alcohol, another chemical classed as an an…


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