Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of pretreatment with equipment bronchodilating doses of intravenous theophyllamine and inhaled terbutaline on the effect of five terbutaline inhalations was investigated in a cross-over study in six adult asthmatics with stable and reproducible bronchoconstriction. Theophylline in a dose giving a maximal mean plasma concentration of 16.7 +/- 1.21 micrograms/ml (92 mumol/l) gave far from maximal acute bronchodilation as the following five terbutaline inhalations gave the same further bronchodilation. Pretreatment with five terbutaline inhalations induced almost equal bronchodilation compared with theophyllamine but the following five inhalations now gave only about one-fourth of the effects recorded after theophyllamine pretreatment. This potentiation could, however, be due to the different routes of administration of the pretreatments. In a randomized, double-blind, cross-over study in eight asthmatic, pretreatment with equipotent oral bronchodilating doses of theophylline and terbutaline was shown to give the same potentiation of the following five terbutaline inhalations. Theoyphylline orally as such thus did not potentiate the effect of inhaled beta 2-stimulants. It had only the same effect as oral terbutaline, but induced less tremor. This means that the potentiation after intravenous and oral pretreatment was not due to theophylline but to the different routes of administrations. Systemic administration probably gave a better distribution and thus better effect of the inhaled terbutaline.
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PMID:Does theophylline potentiate inhaled beta 2-agonists? 612 63

We studied the effect of posture on the sympathoadrenal response to intravenous theophylline in six normal subjects. On three separate occasions they received an intravenous infusion of either theophylline (6 mg/kg) while supine, theophylline (6 mg/kg) while standing or saline as placebo while standing. With the subjects standing theophylline caused tremor, a peak heart rate of 99 +/- 6 beats/min, and an elevation of plasma cyclic AMP from 9.3 +/- 0.7 to 15.1 +/- 1.7 nmol/1 (mean +/- s.e. mean). There was a small, but significant, elevation of plasma adrenaline, noradrenaline and glucose. The elevation in plasma catecholamines was insufficient to explain either the sympathomimetic effects of theophylline or the rise in plasma cyclic AMP. Theophylline had little or no effect with the subjects supine. The mean peak theophylline concentration following infusion was significantly higher with the subjects upright than when supine (18.3 c.f. 12.4 mg/l, P less than 0.025). However, adequate plasma levels of theophylline were obtained in all subjects when lying or supine. Analysis of individual data suggests that differences in plasma levels of theophylline are unlikely to account for the increased effects seen on standing. The mechanism of action of theophylline cannot be explained by increased secretion of catecholamines alone. Theophylline appears to amplify the increased sympathetic activity associated with standing and this is probably by phosphodiesterase inhibition.
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PMID:The effect of posture on the sympathoadrenal response to theophylline infusion. 631 28

Bronchodilating drugs can be divided into three main groups: beta-adrenergic stimulants including specific beta-2 receptor agonists (salbutamol, terbutaline, fenoterol) which are the agents of this group used in everyday practice, theophylline and its derivatives, and atropine-like drugs (ipratropium bromide). Bronchodilators act chiefly upon the spasm observed at the bronchial level in reversible obstructive phenomena (mainly asthma), their effect upon inflammation and hypersecretion being slight or controversial. Beta-stimulants have a relatively specific mode of action at the bronchial level in the setting of use in pneumology; they exhibit cardiac effects only at high doses and when used by oral or parenteral routes. Relative to isoprenaline, they also have the advantage of being active orally and over a longer period of time. They are given in maintenance treatment of asthma, by parenteral or oral routes or as aerosols. Main side effects of adrenergic beta-stimulants are tremor with oral administration, and tachycardia with very high doses by parenteral or oral routes; when given as aerosols these agents may fail to control severe attacks. The bronchodilating properties of theophylline have been known for a long time; late advances concerning this drug result from better knowledge of its pharmacokinetics. Recent studies have discriminated between serum levels correlated with therapeutic effectiveness and those accompanied with mild or severe side effects; in addition, it has been clearly shown that the half life of this alkaloid varies from one person to another and with various physiopathologic (age, dietary habits, liver failure, heart failure...) or pharmacologic (drug interactions with enzyme inductors or inhibitors...) factors; these recent advances have led to improved individual adjustment of theophylline dosage using serum concentration assays if needed. Theophylline is used in acute attacks and in maintenance therapy of asthma. Main side effects are digestive intolerance and, with toxic doses, neurologic disorders. Atropine-like drugs inhibit the effects of the parasympathetic reflex which results from stimulation of receptors by irritation of the respiratory tract, through the action of mediators. In this group, ipratropium is the only drug given in aerosols; this, together with its pharmacologic specificity, contributes to its tolerance. In some instances, the bronchodilating effect of ipratropium bromide is comparable to that of sympathomimetics.
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PMID:[Bronchodilators]. 632 Apr 43

Bronchodilating effects produced by increasing intravenously administered doses of enprofylline and theophylline compared to placebo were evaluated in 20 asthmatic outpatients. Three mean plasma plateaux of enprofylline of 1.5, 2.9 and 4.0 micrograms/ml produced a mean increase in forced expiratory volume in the first second (FEV1.0) as a percentage of baseline, of 12.8%, 18.8% and 30.1%, respectively. Comparable plasma plateaux of theophylline i.e. 5.5, 10.8 and 15.2 micrograms/ml produced a mean increase of FEV1.0 in percent of basal values of 12.4%, 21.6% and 28.2%, respectively. Enprofylline at plasma concentrations above 2.9 micrograms/ml induced more headache and slightly more nausea than theophylline and placebo. Theophylline infusion produced more tremor (finger oscillation) than enprofylline and placebo. Intravenously administered enprofylline produces bronchodilation comparable to theophylline in a mean dose ratio of 3.8.
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PMID:Maximally effective plasma concentrations of enprofylline and theophylline during constant infusion. 648 99

The bronchodilating effect and side-effects of theophylline and a beta 2-adrenoceptor stimulating drug (terbutaline) alone and in combination were studied in 10 adult asthmatic patients. Initially, each individual's pharmacokinetic parameters for theophylline were determined. On 3 separate days, theophylline was infused to defined steady-state concentrations (0, 7.5, and 15 micrograms/mL, respectively) followed by the administration, at intervals of 1 h, of incremental intravenous doses of terbutaline. Theophylline caused a plasma concentration-dependent increase in the volume of air expelled in the first second of forced expiration (FEV1). Theophylline itself had no significant effect on objectively recorded skeletal muscle tremor or heart rate but enhanced the terbutaline-induced increase in both. At the highest steady-state concentration (15 micrograms/mL), 2 of the patients experienced nausea. Terbutaline caused a plasma concentration-dependent increase in FEV1, heart rate and tremor. The plasma levels of terbutaline at the given doses did not differ significantly between individuals or within individuals at different theophylline levels. The combination of theophylline and terbutaline resulted in an additive effect on bronchodilatation. At comparable levels of bronchodilatation, the combination of theophylline and terbutaline caused a lesser degree of side-effects than either drug alone.
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PMID:Simultaneous treatment with terbutaline and theophylline. 658 82

Theophylline and terbutaline, alone and in combination, were evaluated for effectiveness in treating exercise-induced bronchospasm (EIB) when used at doses that should be tolerated by adolescents taking them intermittently: theophylline, 250 mg (fast release) and terbutaline, 2.5 mg. Twenty-one subjects, 12 to 19 years of age, with EIB performed standardized exercise tests on four separate days and received either theophylline, terbutaline, the combination, or placebo in a prerandomized double-blind manner prior to exercise. Exercise tests were performed two and five hours after each study drug administration. Blood samples were drawn before and again two and five hours after drug administration for theophylline level. Pulmonary function [forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and forced expiratory flow rate (FEF 25% to 75%)] was recorded before and after exercise. All of the active treatments were better than placebo in diminishing EIB. The combination was statistically better than terbutaline or theophylline alone. The effect of theophylline was not significantly different from that of terbutaline. The combination induced significantly more tremor than either agent individually. Either drug alone or the two in combination is effective for diminishing EIB. Although the combination may have additive properties for some patients, the increased incidence of tremor may diminish its appeal. Either drug alone or in combination is effective in decreasing EIB for at least five hours, which makes them practical choices for treatment of school-aged children.
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PMID:Effectiveness of terbutaline and theophylline alone and in combination in exercise-induced bronchospasm. 701 39

The bioavailability of three different theophylline tablets (microcrystallinic theophylline, Theolair, Nuelin, 3M Riker), choline theophyllinate as a new film-coated tablet (Teovent, Ferrosan, Sweden) and theophyllaminopropanol (Oxyphylline, Draco, Sweden) was investigated in eight adult asthmatics and a randomized, double-blind, cross-over study. Effects on ventilatory capacity (FEV1 and FVC), circulation (heart rate and blood pressure) and skeletal muscle tremor were followed. The theophylline concentration was determined by gas chromatography. Forty-five minutes after theophylline administration the plasma concentrations were almost the same for all four formulations. The bioavailability was also almost identical. The half-life for intravenous theophylline in these asthmatics was 7.4 +/- 0.64. The three tablet formation had equal effect on FEV1 and the effect was sustained throughout the 6-h period. Six hours after theophylline administration five terbutaline inhalations induced the same further increase in FEV1. The results indicate that theophylline alone has only a moderate acute bronchodilating effect at recommended plasma concentrations but gives a good effect when combined with inhaled beta 2-adrenostimulants.
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PMID:Bioavailability of theophylline from three different tablets in asthmatic patients and their bronchodilating effects in combination with terbutaline inhalation. 713 20

The bronchodilating properties and side effects of theophylline and a beta 2-adrenoceptor stimulating drug (terbutaline) alone and in combination were studied in 10 adult asthmatic patients. Initially, each individual's pharmacokinetic parameters for theophylline were determined. On 3 separate days theophylline was infused to defined steady-state concentrations (0, 7.5, and 15 microgram/ml, respectively) followed by the administration, at 1-h intervals, of incremental i.v. doses of terbutaline. It was shown that: 1. Theophylline caused a concentration-dependent increase in FEV1. Theophylline itself had no significant effect on objectively recorded skeletal muscle tremor or heart rate but enhanced the terbutaline-induced increase in tremor and heart rate. At the highest concentration (15 microgram/ml) two of the patients experienced nausea. 2. Terbutaline caused a concentration-dependent increase in FEV1, heart rate, and tremor. The plasma levels of terbutaline at the given doses did not differ significantly between individuals or within individuals at the different theophylline levels. 3. The combination of theophylline and terbutaline resulted in a mere additive effect on the bronchodilatation. At comparable bronchodilatation the combination of theophylline and terbutaline caused a lesser degree of side effects than each of the drugs alone.
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PMID:Separate and combined use of terbutaline and theophylline in asthmatics. Effects related to plasma levels. 714 Aug 72

Propranolol, which has long been used as the standard treatment for essential tremor, has been compared with placebo and theophylline in ten newly diagnosed patients without other, prior drug treatments. Patients were treated for four weeks with one drug, followed by placebo for four weeks, and then the second drug for the same period, in a blind cross-over trial. Tremor was quantified using the volumetric method, and was decreased significantly after one week on propranolol, 80 mg/day. Theophylline 150 mg/day reduced tremor to the same extent, although the improvement was not significant until the second week. Three patients reported side effects on propranolol. It is suggested that theophylline may be a useful alternative agent in the treatment of essential tremor, probably due to a chronic up-regulation of adenosine receptors.
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PMID:Efficacy of an adenosine antagonist, theophylline, in essential tremor: comparison with placebo and propranolol. 854 37

Theophylline toxicity has been recognized since its introduction into clinical medicine. Clarithromycin is a new oral macrolide antibiotic with excellent antibacterial activity and rare adverse effect. Patients with upper respiratory infection are often treated with theophylline and clarithromycin concurrently. We report a case of acute renal failure due to acute rhabdomyolysis caused by the interaction of theophylline and clarithromycin. A 72-year-old man visited our hospital because of coughing and a sore throat continuing for 1 week. He was diagnosed as having the common cold with a bronchial asthmatic symptom and was prescribed 200 mg/day of sustained-release theophylline for the treatment of asthma for 7 days. One week later, he visited our hospital again. Radiographic study of the chest revealed mild interstitial pneumonia and 200 mg/day of sustained-release theophylline and 400 mg/day of clarithromycin were administrated concomitantly. Five days after the second visit, the patient was admitted to our hospital because of generalized twitching, muscular weakness, high fever and serious general condition. He experienced generalized muscular twitching and tremor. Blood urea nitrogen was 106.1 mg/dl, serum creatinine was 7.4 mg/dl, serum creatinine kinase (CK) was 36,000 IU/l (normal 15-130 IU/l), CK isozyme revealed the following ratio: BB 0%, MB 1% and MM 99%. He was diagnosed as having acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin. Hemodialysis therapy was started. After 5 weeks, his serum creatinine was markedly decreased. It is well-known that clarithromycin enhances the serum concentration of theophylline by inhibition of the cytochrome P450-dependent pathway in hepatocytes. Theophylline toxicity may be enhanced when clarithromycin is administrated concomitantly, especially to elderly patients with dehydration.
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PMID:[A case of acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin]. 1044 97


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