Talk:Theophylline

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  • Is theophyline naturally derived from plant sources, or is it synthesized in test tube?
    • Both. There's no difference between natural and artificial theophylline - they're 100% exactly the same.12:12, 10 Nov 2004 (UTC)
  • What is a "positive inotropic effect" and a "positive chronotropic effect"? Does that mean increase or decrease in either? Using the links doesn't help.
    • positive inotropic effect -> it increases heart muscle contractility and efficiency
    • positive chronotropic effect -> it increases the heart rate.
    • The links will be even less help when they're moved to Wiktionary! - Nunh-huh 15:33, 24 Mar 2005 (UTC)


What amount of theophylline is there in a cup of black tea? Is there any in coffee?

Contents

[edit] Correction: Ratio of Metabolized Substances

Caffeine is metabolized in the liver into three primary metabolites: 
paraxanthine (84%), theobromine (12%), and theophylline (4%) 
Reference: # ^ Caffeine. The Pharmacogenetics and Pharmacogenomics Knowledge Base.
Retrieved on 2006-08-14.
  • This reference is somewhat out of date. According to the same source [1], cross-referenced by Theobromine, the ratios listed in Caffeine are incorrect.

[edit] How safe is this?

Q:If theophylline is naturally occuring in green tea, than how much is occuring in a cup? What are the effects for someone on medication to this combination?

Hopefully someone else can answer the amount question. I don't know what you mean by the second one, but if you mean a combination of black tea and taking theophylline pills, then yes that could contribute to excess amounts and thus toxicity. - Taxman Talk 20:01, August 15, 2005 (UTC)

Q: What are the effects of infusing theophylline and guarna into the same concentrate?

Presumably you mean guarana which contains caffeine? No idea. Unless that's been studied it could have little to no interaction, or a significant adverse reaction. That's one of the big problems with homeopathic medicine, is the lack of information about their adverse reactions with other drugs. To answer your general question, Theophylline can be significantly toxic and as far as I know, it is generally a last resort type drug, only to be used when nothing else works or works well enough. At least here in the US that is. - Taxman Talk 20:01, August 15, 2005 (UTC)
Taxman: An infusion or a concentrate can not be considered homeopathic because they contain conspicuous quantities of herbal extracts. Tea and/or guarana as medicine could be considered herbal medicine.

[edit] Theophylline and COPD

Recent research at Imperial College London under Prof Peter Barnes has demonstrated that low doses of theophylline raise the level of the enzyme HDAC2, which may then allow glucocorticoids to reduce lung inflamation, which they are not normally effective at with COPD patients. The doses used in the trials were much less than used when theophylline was once a commonly prescribed bronchodilator for COPD treatment.

Steroids are normally quite effective in COPD patients. Theophylline is still in fairly common use in patients refractory on short- and longterm bronchodilators and inhaled steroids. JFW | T@lk 17:08, 7 March 2006 (UTC)

"In chronic obstructive pulmonary disease (COPD) patients and asthmatic patients who smoke HDAC2 is markedly impaired as a result of oxidative and nitrative stress so that inflammation is resistant to the anti-inflammatory effects of corticosteroids." Barnes PJ, Eur J Pharmacol.2006 Mar 8;533(1-3):2-14. --Onefishtwofish 12:20, 2 July 2006 (UTC)

[edit] Bioavailability

From the article: 'Bioavailability is 100%. However, taking the drug late in the evening may slow the absorption process, without affecting the bioavailability. Taking the drug after a meal high in fat content will also slow down the absorption process, without affecting the bioavailability. There is one exception. Taking UniphylTM, a long-acting theophylline formulation, after a meal high in fat content will increase its bioavailability.'

I am completely ignorant of what bioavailability means, but I'm guessing that it isn't supposed to exceed 100%, making this a rather curious statement, since it implies > 100% bioavailability w/ the use of some product. --anonymous, 31 March, 2008 —Preceding unsigned comment added by 75.172.48.115 (talk) 17:44, 31 March 2008 (UTC)