The Effect of Verapamil on the Pharmacokinetic Disposition of Theophylline in Cigarette Smokers

  title={The Effect of Verapamil on the Pharmacokinetic Disposition of Theophylline in Cigarette Smokers},
  author={Azusa Gin and Kathleen A. Stringer and Lynda S. Welage and John H. Wilton and G E Matthews},
  journal={The Journal of Clinical Pharmacology},
In a randomized cross‐over study the effect of verapamil on the pharmacokinetics of theophylline was evaluated in eight cigarette smoking male volunteers. Theophylline was administered as an intravenous infusion of aminophylline, 6 mg/kg based on ideal body weight, over 30 minutes in the control phase. In the treatment phase, aminophylline was administered after a four day regimen of oral verapamil 80 mg every 8 hours. Serial blood samples were collected over a 24 hour period following… Expand
The effect of three different oral doses of verapamil on the disposition of theophylline
The results suggest that the inhibitory effect of verapamil on the pharmacokinetic disposition of theophylline is directly related to verAPamil dose. Expand
Influence of Endogenous and Exogenous Effectors on the Pharmacokinetics of Theophylline
Age and concomitant disease are the major endogenous effectors influencing biotransformation of theophylline, whereas biorhythms, gender and pregnancy are of lesser importance. Expand
Theophylline and Verapamil: Clinically Significant Drug Interaction
Although the most recent FDA labeling guidelines for theophylline mention verapamil as a documented source of drug interaction with theophyLLine, many clinicians may not realize the potential clinical significance of this interaction. Expand
Pharmacokinetic Interactions with Calcium Channel Antagonists (Part I)
Interactions between calcium antagonists and marker compounds, theophylline, midazolam, lithium, doxorubicin, oral hypoglycaemics and cardiac drugs are dealt with. Expand
Pharmacokinetic Interactions Between Theophylline and Other Medication (Part II)
SummaryPart I of this article, which appeared in the previous issue of the Journal, covered the effects or lack of effects on theophylline clearance of sympathomimetics, corticosteroids,Expand


Effect of calcium channel blockers on theophylline disposition
The modest reduction in theophylline clearance observed after verapamil and diltiazem is not likely to produce clinically significant increases in thephylline concentrations in most patients. Expand
Selective inhibitory effects of nifedipine and verapamil on oxidative metabolism: effects on theophylline.
Verapamil and nifedipine at usual clinical doses are unlikely to cause clinically significant changes in theophylline disposition. Expand
Changes in antipyrine and indocyanine green kinetics during nifedipine, verapamil, and diltiazem therapy
Drug interactions with other liver‐metabolized drugs may occur during therapy with these calcium antagonists and nifedipine appears to increase liver blood flow whereas diltiazem inhibits oxidative drug metabolism. Expand
Substrate-selective inhibition by verapamil and diltiazem: differential disposition of antipyrine and theophylline in humans.
Antipyrine and theophylline disposition was studied in healthy volunteer subjects in the control state while the subjects were taking verapamil orally four times daily or diltiazem orally three times daily, resulting in prolonged antipyrine half-life with no change in distribution volume. Expand
Enhanced biotransformation of theophylline in marihuana and tobacco smokers
Concern over enhanced metabolism of other drugs is probably warranted in tobacco and cannabis smokers and theophylline was cleared from the blood more rapidly in both marihuana and tobacco smokers. Expand
Inhibition of hepatic microsomal drug metabolism by the calcium channel blockers diltiazem and verapamil.
  • K. Renton
  • Chemistry, Medicine
  • Biochemical pharmacology
  • 1985
Results suggest that diltiazem and verapamil may have the potential to cause drug interactions involving inhibition of drug biotransformation, as both drugs could prolong pentobarbital-induced sleeping times in mice at doses comparable to those used in man. Expand
Influence of cigarette smoking on drug metabolism in man.
  • W. Jusko
  • Medicine
  • Drug metabolism reviews
  • 1979
Smoking is only one of numerous factors which can perturb hepatic biotransformation as patient surveillance studies show that age and cardiac and liver disease may be of greater importance in actual patients undergoing therapy. Expand
Calcium Antagonists in the Management of Asthma: Breakthrough or Ballyhoo?
Data has been generated on the effects of verapamil, diltiazem, nifedipine, and several investigational agents on experimentally induced asthma, indicating that none of these agents significantly affects resting bronchomotor tone, and their efficacy in preventing bronchospasm is a function of the drug, dose, route of administration and method of bronchoprovocation. Expand
Induction and inhibition of drug metabolism
The study of drug metabolism in experimental animals in general and Man in particular is ideally studied under strictly controlled conditions, such that we only observe the influence of the normalExpand
Calcium-channel blocking agents for gastrointestinal disorders.
There is no experimental evidence of a major antisecretory effect of calcium-channel blocking drugs in therapy of gastrointestinal disease, but nifedipine has been shown to have a greater effect than placebo in improving symptoms in patients with achalasia, and diltiazem has been suggested as potential therapy in Patients with chest pain secondary to excessive esophageal contraction. Expand