Baseline laboratory monitoring for ziprasidone should include which electrolytes in at-risk individuals or those on diuretics?

• A. Serum Potassium and Magnesium
• B. Baseline CBC
• C. Baseline LFTs
• D. Fasting Glucose and HbA1c

Answer: (A)

The main concept is assessing QT risk with a medication that can prolong the heart’s electrical activity by watching electrolytes that affect repolarization. Ziprasidone can lengthen the QT interval, so low levels of certain electrolytes increase the danger of dangerous arrhythmias. Potassium and magnesium are the key players here: when either is depleted, the QT prolongation risk rises, and this is particularly true in people taking diuretics, which commonly cause losses of these electrolytes. Checking serum potassium and magnesium before starting ziprasidone in at‑risk individuals or those on diuretics helps identify imbalances that should be corrected to reduce arrhythmia risk. Other baseline tests like CBC, liver enzymes, or glucose metrics don’t directly address QT risk, so they’re not the best focus for this specific monitoring need.