Dofetilide (Tikosyn) Tips from Pharmacists

• Patients initiated on dofetilide need to stay in the hospital for 3 days (6 doses) when starting or restarting dofetilide (Tikosyn) treatment. This allows healthcare providers to find the right dose that does not cause serious problems like prolongation of the QT interval. The QT interval is the effective refractory period (reset time) between heartbeats. While in the hospital, an ECG is done 2 hours after each dose when the plasma concentration of dofetilide peaks. Based on plasma concentrations and their effect on the QT interval, the hospital stay may need to be longer for dosage adjustment.

• Swallow the capsule whole. Do not cut, crush, or open it.

• You can take dofetilide capsules with or without food. Try to take the medicine at the same time every day to maintain steady state plasma concentrations.

• Avoid eating grapefruit or drinking grapefruit juice while on dofetilide. Grapefruit can increase the plasma concentration of the drug and increase the risk of side effects.

• Check with your doctor before starting or stopping any new medication while on dofetilide. Drug interactions can put you at risk of serious side effects.