Theophylline


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Related to Theophylline: salbutamol

theophylline

[‚thē·ə′fī‚lēn]
(organic chemistry)
C7H8N4O2·H2O Alkaloid from tea leaves; bitter-tasting white crystals slightly soluble in water and alcohol, melts at 272°C; used in medicine.

Theophylline

 

(1,3-dimethylxanthine), an alkaloid of the group of urines; small quantities are found in tea leaves. In pharmacological activity, theophylline is similar to theobromine, from which it differs in its more pronounced diuretic action. Theophylline dilates the blood vessels of the heart and the bronchial musculature and excites the central nervous system. It is prescribed internally, in powder form, and rectally, as suppositories. It is a constituent of Teofedrin and other compound preparations. It is obtained by chemical synthesis from dimethylurea and ethyl cyanoacetate.

References in periodicals archive ?
Immunoassays for theophylline were performed on the Hitachi 917 analyzer as follows: 3 [micro]L of sample was added to a cuvette, and 150 [micro]L of R1 reagent was added, mixed, and incubated at 37[degrees]C for 5 min.
And the results of a randomized trial of inhaled beclomethasone compared with oral theophylline found similar rates of asthma exacerbation during pregnancy with the two drugs.
Examination of cases reported to the FDA revealed a mean percentage increase in serum theophylline concentrations of 114% when ciprofloxacin or norfloxacin were given concomitantly with theophylline.[34] Fourteen of 39 patients receiving ciprofloxacin and theophylline experienced a seizure, and three of nine patients on concurrent norfloxacin and theopylline had this same adverse event.[34] Analysis of reports to the FDA further revealed that the elderly are at increased risk for this interaction.
This small study (42 patients were enrolled, 11 were disqualified for not taking the medicine properly) didn't demonstrate any subtle changes due to theophylline. A small number of children do experience significant side effects from theophylline (stammering, depression, and psychosis).
Caffeine or theophylline can also cause tachycardia, and the cerebral vasoconstricting effect has been used to treat migraine headaches.
Loading dose 4.4-9 mg/kg and maintenance dose 2-12 mg/kg/day have been used accomplishing plasma levels between 4-24 mg/L whereas levels as little as 1.3mg/dL are observed as efficacious.8 A strong recommendation of therapeutic monitoring has been made in order to get the therapeutic levels of theophylline between 5-12 mg/L.
Adolescent or school-aged children with severe persistent asthma (step 4) should take a medium or high dose of ICS together with LABA, with the authors recommending adding tiotropium to a soft-mist inhaler, combination high-dose ICS and LTRA, or a combination high-dose ICS and theophylline.
It has been suggested that the therapeutic effects of caffeine are affected by the expression and type of CYP1A2 isoform present (main metabolic pathway), which affects not only plasma concentration of caffeine (Caf) and its metabolites (theophylline (Theo), theobromine (Theb), and paraxanthine (Par)) (Figure 1) but also its therapeutic effects [13-15].
That's how Janda's team discovered that Captagon produces its combat-boosting effects from a functional synergy between amphetamine and theophylline.
In adults, a dose of two MDI actuations two or four times daily has been shown to provide equal or better control of mild to moderate asthma compared with theophylline. This is based on daytime and nighttime asthma symptoms, need for inhaled bronchodilator, cough and morning tightness.
In the case of the theophylline tablets, each row represents a certain polymer concentration and contains the reflectance values for each wavelength, averaged over several samples and measurements.
Theophylline used to be used to treat COPD on its own but its use at high dose as a drug to open up airways has declined with the development of new inhaled treatments.