For a patient initiated on dofetilide, which medication should be avoided to prevent interactions?

Dofetilide is an antiarrhythmic medication used primarily for the treatment of atrial fibrillation and atrial flutter. It is crucial to avoid certain medications that can lead to interactions, particularly those that may increase the risk of dofetilide toxicity.

Hydrochlorothiazide can significantly impact renal function and may affect the elimination of dofetilide, leading to increased drug levels and a higher risk of serious adverse effects, including Torsades de Pointes. Dofetilide is primarily excreted by the kidneys, and any medication that alters renal function or the renal clearance of dofetilide can contribute to toxicity.

In contrast, amlodipine, sertraline, and lisinopril do not have the same significant interactions with dofetilide. Amlodipine is a calcium channel blocker with a different mechanism and is generally considered safe to use with dofetilide. Sertraline, an SSRI, may also be used with caution as it does not significantly impact the metabolism or renal clearance of dofetilide. Lisinopril, an ACE inhibitor, does not pose the same risk of interaction as hydrochlorothiazide does, making it a