Skip to main content

Drug Interactions between Digitek and vandetanib

This report displays the potential drug interactions for the following 2 drugs:

Edit list (add/remove drugs)

Interactions between your drugs

Moderate

digoxin vandetanib

Applies to: Digitek (digoxin) and vandetanib

MONITOR: Coadministration with vandetanib may increase the plasma concentrations of drugs that are substrates of the P-glycoprotein transporter, such as digoxin and dabigatran. The mechanism involves increased absorption and/or decreased clearance due to inhibition of drug efflux mediated by intestinal and renal/hepatic P-glycoprotein, respectively. Vandetanib is a weak P-glycoprotein inhibitor. The clinical significance is unknown. In healthy subjects, coadministration of a single 0.25 mg dose of digoxin with a 300 mg dose of vandetanib increased the mean digoxin Cmax by 29% and the mean AUC by 23%.

MANAGEMENT: Caution is advised if vandetanib must be used concomitantly with medications that are substrates of P-glycoprotein, particularly those with a narrow therapeutic range such as digoxin. Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs whenever vandetanib is added to or withdrawn from therapy.

References (4)
  1. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  2. EMEA. European Medicines Agency (2007) EPARs. European Union Public Assessment Reports. http://www.ema.europa.eu/ema/index.jsp?curl=pages/includes/medicines/medicines_landingpage.jsp&mid
  3. Cerner Multum, Inc. "Australian Product Information."
  4. (2011) "Product Information. Vandetanib (vandetanib)." Astra-Zeneca Pharmaceuticals

Drug and food interactions

Minor

digoxin food

Applies to: Digitek (digoxin)

Administration of digoxin with a high-fiber meal has been shown to decrease its bioavailability by almost 20%. Fiber can sequester up to 45% of the drug when given orally. Patients should be advised to maintain a regular diet without significant fluctuation in fiber intake while digoxin is being titrated.

Grapefruit juice may modestly increase the plasma concentrations of digoxin. The mechanism is increased absorption of digoxin due to mild inhibition of intestinal P-glycoprotein by certain compounds present in grapefruits. In 12 healthy volunteers, administration of grapefruit juice with and 30 minutes before, as well as 3.5, 7.5, and 11.5 hours after a single digoxin dose (0.5 mg) increased the mean area under the plasma concentration-time curve (AUC) of digoxin by just 9% compared to administration with water. Moreover, P-glycoprotein genetic polymorphism does not appear to influence the magnitude of the effects of grapefruit juice on digoxin. Thus, the interaction is unlikely to be of clinical significance.

References (2)
  1. Darcy PF (1995) "Nutrient-drug interactions." Adverse Drug React Toxicol Rev, 14, p. 233-54
  2. Becquemont L, Verstuyft C, Kerb R, et al. (2001) "Effect of grapefruit juice on digoxin pharmacokinetics in humans." Clin Pharmacol Ther, 70, p. 311-6

Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

See also

Report options

Loading...
QR code containing a link to this page

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer