Talk:Phenytoin

From Wikipedia, the free encyclopedia

This is the talk page for discussing improvements to the Phenytoin article.
Article policies
Phenytoin is part of WikiProject Pharmacology, a project to improve all Pharmacology-related articles. If you would like to help improve this and other pharmacology articles, please join the project. All interested editors are welcome.
Start This article has been rated as start-Class on the quality scale.
High This article has been rated as high-importance for this Project's importance scale.

Contents

[edit] New Comment

I'll leave it to someone who cares about this article to fix it, but "chronically high levels" is jibberish.

Dave

[edit] Old Stuff

It says here that Jack Dreyfus prescribed phenytoin to Richard Nixon. This can't be right; first of all, Dreyfus is not a physician, and has never represented himself as one.

I'm going to remove that sentence, reword that paragraph a bit, and replace it with a link at the bottom to a web site about Dreyfus' efforts to expand the indications for phenytoin.

-Ikkyu2 23:56, 28 August 2005 (UTC)

I saw a TV programme about this around 2000, which implied that President Nixon was high (or more likely low) on drugs when he made decisions: it said Dreyfus gave him a bottle of phenytoin. Presumably Nixon's own physician would have prescribed for him when he needed more. That phenytoin could damp down mood swings, and aggressive or other impulses, is not implausible: the bromides were used for this, and currently carbamazepine and valproate, and some newer anticonvulsants, so this may be a class effect of many, if not all, of these drugs. NRPanikker 01:09, 19 October 2006 (UTC)

[edit] Mechanism

Someone added the following text to the article to-day:

The primary site of action appears to be the motor cortex where spread of seizure activity is inhibited. Possibly by promoting sodium efflux from neurons, phenytoin tends to stabilize the threshold against hyperexcitability caused by excessive stimulation or environmental changes capable of reducing membrane sodium gradient. This includes the reduction of posttetanic potentiation at synapses. Loss of posttetanic potentiation prevents cortical seizure foci from detonating adjacent cortical areas. Phenytoin reduces the maximal activity of brain stem centers responsible for the tonic phase of tonic-clonic (grand mal) seizures.

This text is so interesting, pertinent and provocative that I would like to commend the person who placed it for the addition to the article. Also, I believe that it would benefit greatly from sourcing - e.g. from where was this information derived? Once that can be cited, it will certainly be appropriate to put the text back into the article. -ikkyu2 (talk) 22:33, 7 March 2006 (UTC)

Here's one source: http://www.rxlist.com/cgi/generic/phenyt_cp.htm . Don't know where rx-list gets their information from, it looks like a standard blurb of some kind. --Pfh 00:39, 11 July 2006 (UTC)

[edit] Antiarrhythmic?

This is in the category Antiarrhythmic agents, but there is no mention of it in the article. --Galaxiaad 08:52, 1 March 2007 (UTC)

[edit] Comment

  1. Antiarrhythmic : CBZ is not in the Vaughan-Williams Classification of Antiarrhythmics (see any text) although it is sometimes referred to as a "membrane stabilizer".
  2. I'm not sure if the toxicities are presented so clearly (in the paragraph "Side Effects"). As I understand, the gum hyperplasia, coarse facial features and hursuitism are common and dose related and the most significant and so they should feature prominently in the article (due to the distress they cause patients).
  3. I understand that the teratogenic potential is certain (Holmes LB, Harvey EA, Coull BA, et al. The teratogenecity of anticonvulsant drugs. N Engl J Med 2001;344:1132—8.)
  4. Additionally, I thought that the hypersensitivity reactions and skin / liver and bone reactions, whilst rare, are definitely associated with phenytoin. Some texts are vague on this point.
  5. I thought this review article regarding the associated Folate-deficiency, Ann Pharmacother. 1995 Jul-Aug;29(7-8):726-35, [[1]] (although also old) is a bit more useful than a 1992 study with rats.
  6. I'll aim to chase up a list of solid references when time permits.
  7. My personal opinion regarding the use of phenytion and the reluctance of the medical staff to prescribe (it in the Devloped World) is not "... due to mixed results from various studies" but because its common, predictable and significant adverse effects make it a very undesirable drug to use in the majority of the patient population. Note, that it is in guidelines for the Acute Management of Status Epilepticus as the first choice drug for Second line therapy so still has a signicant role (see either APLS, or Status Epilepticus Working Party (United Kingdom 2000)). (Again, IMHO) there seems to be significant bias as the article reads currently.

[edit] Price Increase

Does anyone have any information on the sudden and dramatic price increase on Phenytoin Sodium Extended? I work for a pharmacy and have been faced with this question from many customers, and I agree it has jumped significantly recently, but the internet has not provided any information as to why.Sithboy 00:28, 23 August 2007 (UTC)

[edit] Nootropic

Apparently this is sometimes used as a Nootropic. Can anyone shed any further light on this, e.g. what the benefits are (if any)? --212.159.16.241 (talk) 00:12, 26 January 2008 (UTC)


[edit] Suicide Risk

I've re-added that the FDA found an increased risk of suicide from users of epilepsy drugs. This paragraph was removed by another user as phenytoin was not explicitly named in the article, but I feel it should be included as the FDA explicitly stated that it expects the risk to apply to every epilepsy drug in the article. This was clarified in my submission. Please discuss before removing this addition.

Amcarroll32 (talk) 13:09, 6 February 2008 (UTC)