digoxin and Asthma

Clinical uses of calcium channel blockers are expanding. In addition to the established uses in patients with arrhythmias, angina pectoris or hypertension, newer and to some extent investigational uses indicate widespread application. For instance, their use has been reported in hypertrophic cardiomyopathy and cold cardioplegia, as well as in pulmonary hypertension, antiplatelet therapy, asthma, achalasia and oesophageal spasm, increased intraocular pressure and in cerebral vasospasm. Their use in obstetrical practice has been proposed. Thus, the presentation of a patient who is treated with calcium channel blockers and who requires anaesthesia will become more common. Calcium channel blockers may, under certain circumstances, potentiate haemodynamic and MAC depressive effects of inhalation agents. There is also evidence that the effects of neuromuscular blocking agents may be potentiated. The anaesthetist should be aware that the potential for interactions exists with digoxin, propranolol, quinidine, theophylline or dantrolene. Of interest and some significance are the anaesthetic implications of pathophysiological alterations that can be induced by calcium channel blockers, by affecting lower oesophageal tone, intracranial hypertension, bronchomotor tone (asthma), muscular dystrophy, neuromuscular function, hypoxic pulmonary vasoconstriction, malignant hyperthermia, inhibition of platelet aggregation and hyperkalemia. Despite these significant potential anaesthetic implications and because, at this time, in some instances withdrawal has clearly demonstrated increase in the signs of myocardial ischaemia, it would not seem necessary to recommend preoperative discontinuation of calcium channel blocker medication in patients presenting for anaesthesia. It is, however, appropriate that there is a high index of awareness of potential problems, unless there is some modification in inhalation anaesthetic concentrations and neuromuscular blocker dosage. Monitoring of cardiovascular and neuromuscular functions is essential. Calcium channel blockers would appear to be currently the drugs of choice for angina pectoris, arrhythmias or hypertension in patients with associated chronic obstructive pulmonary disease.

Topics: Adrenergic beta-Antagonists; Anesthesia; Anesthetics; Animals; Asthma; Calcium; Calcium Channel Blockers; Dantrolene; Digoxin; Drug Interactions; Esophagus; Humans; Hyperkalemia; Intracranial Pressure; Malignant Hyperthermia; Neuromuscular Blocking Agents; Quinidine; Theophylline; Vasoconstriction

Topics: Analgesics; Anti-Bacterial Agents; Anticoagulants; Asthma; Blood Transfusion; Contraceptives, Oral; Digoxin; Drug Interactions; Drug Therapy; Humans; Infusions, Parenteral; Leukemia; Lymphoma; Prostaglandins

A number of studies have shown that increased salt intake is associated with worsening asthma. The aim of this study was to investigate the respiratory effects of digoxin (a potent inhibitor of Na+K+ATPase) in patients with asthma.. Eight asthmatic patients were given digoxin (0.5 mg/daily) or matching placebo for 8 days. Treatments were assigned using a randomised double blind, crossover design. Bronchial hyperresponsiveness to methacholine, forced expiratory volume is one second (FEV1, serum potassium (K), urinary sodium and K, heart rate, blood pressure and the QTc interval of the ECG were measured on each treatment.. When compared to placebo, digoxin significantly decreased FEV1 (p<0.03); the QTc interval (p<0.05), and increased serum K (p<0.02). There was a tendency for digoxin to increase bronchial hyperresponsiveness.. In this small study digoxin resulted in a decline in spirometry. Further studies in a larger group of patients should be performed to assess this potentially adverse effect of digoxin.

Topics: Adult; Asthma; Bronchial Hyperreactivity; Bronchial Provocation Tests; Cross-Over Studies; Digoxin; Double-Blind Method; Enzyme Inhibitors; Forced Expiratory Volume; Humans; Male; Middle Aged; Pilot Projects

1. We have recently shown that ouabain, an inhibitor of Na+/K(+)-adenosine triphosphatase, causes contraction of bovine and human airways in vitro, and that amiloride causes relaxation and inhibits receptor-operated contraction in bovine trachealis. 2. To determine whether such drugs alter bronchial reactivity in vivo, we have studied the effect of oral digoxin (an inhibitor of Na+/K(+)-adenosine triphosphatase) and oral and inhaled amiloride on bronchial reactivity to histamine in three double-blind, placebo-controlled studies. 3. Histamine reactivity was measured as the provocative dose causing a 20% reduction in the forced expiratory volume in 1 s (PD20FEV1) or, when normal subjects were included, the provocative dose causing a 35% reduction in the specific airways conductance (PD35sGaw); the results are given as geometric mean values. 4. In study 1, 13 atopic asthmatic subjects were given 20 mg of oral amiloride or placebo on separate days. Two hours after the drug, the geometric mean PD20FEV1 for histamine was 0.43 mumol after amiloride and 0.54 mumol after placebo (95% confidence intervals for the difference: 0.9 to -0.2 doubling doses of histamine; P = 0.2). 5. In study 2, six normal and 24 atopic asthmatic men inhaled 10 ml of 10(-2) mol/l amiloride or diluent control in a crossover study. The mean values of PD35sGaw for histamine immediately after inhalation of amiloride and placebo were 3.0 mumol and 4.3 mumol, respectively, in the normal subjects (95% confidence intervals for the difference: -0.53 to 1.52 doubling doses, P = 0.2), and 0.33 mumol and 0.29 mumol in the asthmatic subjects (95% confidence intervals for the difference: -0.95 to 0.57 doubling doses; P = 0.6).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Aged; Amiloride; Asthma; Bronchi; Digoxin; Dose-Response Relationship, Drug; Double-Blind Method; Female; Forced Expiratory Volume; Histamine; Humans; Male; Middle Aged; Peak Expiratory Flow Rate; Sodium-Potassium-Exchanging ATPase

The isoprenoid pathway produces three key metabolites--digoxin (membrane sodium-potassium ATPase inhibitor and regulator of neurotransmitter transport), dolichol (regulator of N-glycosylation of proteins), and ubiquinone (free radical scavenger). The isoprenoid pathway was assessed in patients with bronchial asthma. The pathway was also assessed in patients with right hemispheric, left hemispheric, and bihemispheric dominance to find out the role of hemispheric dominance in the pathogenesis of bronchial asthma. The pathway was upregulated with increase in digoxin synthesis in bronchial asthma. There was an increase in tryptophan catabolites and a reduction in tyrosine catabolites in patients with bronchial asthma. The ubiquinone levels were low and lipid peroxidation increased in these patients. There was increase in dolichol and glycoconjugate levels and reduction in lysosomal stability in these patients. The cholesterol:phospholipid ratio was increased and glycoconjugate levels were reduced in the membranes of these patients. The patterns noticed in bronchial asthma were similar to those in patients with right hemispheric chemical dominance. Bronchial asthma occurs in right hemispheric chemically dominant individuals. Ninety percent of the patients with bronchial asthma were right-handed and left hemispheric dominant by the dichotic listening test. But their biochemical patterns were similar to those obtained in right hemispheric chemical dominance. Hemispheric chemical dominance is a different entity and has no correlation with handedness or the dichotic listening test.

Topics: Adult; Analysis of Variance; Asthma; Digoxin; Dominance, Cerebral; Free Radicals; Humans; Hypothalamus

Topics: Adrenergic beta-Agonists; Albuterol; Asthma; Child; Digoxin; Drug Interactions; Humans; Isomerism

Topics: Asthma; Digoxin; Drug Therapy; Heart Diseases; Humans; Theophylline

Topics: Adolescent; Age Factors; Asthma; Child; Creatinine; Digoxin; Female; Humans; Male; Natriuretic Agents; Osmolar Concentration

An adaptation of a previously published program for nonlinear regression analysis of serum drug concentrations which can utilize data obtained during multiple-dose administration is described. Specific programs have been developed for aminoglycosides, digoxin, and theophylline. The programs provide initial parameter estimates (for a one-compartment linear model) for each drug based on mean population parameters and refined estimates based on observed concentration data. Clinical examples which demonstrate the flexibility of these programs are provided. The programs may also be employed for fitting data for any drug that can be adequately described by a one-compartment linear model.

Topics: Adult; Aged; Amikacin; Aminophylline; Asthma; Atrial Fibrillation; Computers; Digoxin; Female; Humans; Leukemia; Male; Microcomputers; Pharmaceutical Preparations; Regression Analysis; Software

Topics: Aged; Aminophylline; Anti-Bacterial Agents; Asthma; Bronchitis; Digoxin; Diuretics; Emergencies; Expectorants; Humans; Hypoxia; Lung; Prednisolone; Respiration, Artificial; Terbutaline; Vital Capacity

Topics: Adolescent; Asthma; Digoxin; Humans; Male; Propranolol; Tachycardia, Paroxysmal

Topics: Asthma; Blood Circulation; Blood Transfusion; Brain Edema; Child, Preschool; Coma; Digoxin; Heart Massage; Humans; Male; Mannitol; Medication Errors; Respiration, Artificial; Seizures; Tachycardia; Theophylline

Topics: Aged; Asthma; Bronchitis; Carbon Dioxide; Cardiac Catheterization; Conjunctiva; Diet, Sodium-Restricted; Digoxin; Edema; Eye Diseases; Female; Furosemide; Heart Failure; Humans; Hyperemia; Male; Middle Aged; Oxygen; Oxygen Inhalation Therapy; Potassium Chloride; Pulmonary Emphysema; Pulmonary Fibrosis; Pulmonary Heart Disease; Respiratory Insufficiency; Veins

Topics: Asthma; Bronchitis; Bronchopneumonia; Digoxin; Heart Failure; Humans; Infant; Lanatosides

Topics: Asthma; Biomedical Research; Blood Pressure; Blood Pressure Determination; Bronchitis; Cardiac Catheterization; Digitalis; Digoxin; Electrocardiography; Eosinophilia; Humans; Lung Diseases; Pharmacology; Pulmonary Artery; Pulmonary Emphysema