Drug interactions
Chlorthalidone + Furosemide
Severity: Moderate
Chlorthalidone and Furosemide: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Combining a thiazide-type and a loop diuretic results in a strong synergistic diuresis, useful in resistant edema but risky. Severe hypokalemia, hyponatremia, hypomagnesemia, dehydration and renal impairment may occur.
What this interaction means in plain words
Chlorthalidone and Furosemide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Chlorthalidone belongs to Cardiovascular; Furosemide belongs to Cardiovascular.
Why it happens
Sequential nephron blockade increases distal sodium delivery, enhancing urinary loss of sodium, potassium and magnesium.
What to do
Monitor electrolytes, renal function and weight closely, especially in the first days. Replace potassium and magnesium and lower diuretic doses if excessive diuresis develops.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Chlorthalidone
Other interactions of Furosemide
- Amifostine + Furosemide Major
- Amikacin + Furosemide Major
- Carbenoxolone + Furosemide Major
- Cephaloridine + Furosemide Major
- Cisplatin + Furosemide Major
- Digoxin + Furosemide Major
Frequently asked questions
Can I take Chlorthalidone with Furosemide?
MediHelp rates the interaction as moderate. Chlorthalidone and Furosemide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Combining a thiazide-type and a loop diuretic results in a strong synergistic diuresis, useful in resistant edema but risky. Severe hypokalemia, hyponatremia, hypomagnesemia, dehydration and renal impairment may occur.
How serious is the interaction between Chlorthalidone and Furosemide?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor electrolytes, renal function and weight closely, especially in the first days. Replace potassium and magnesium and lower diuretic doses if excessive diuresis develops.
What other medicines interact with Chlorthalidone?
MediHelp also lists interactions of Chlorthalidone with, for example, Amifostine, Atenolol-chlorthalidone, Candesartan-hydrochlorothiazide. The full list is on the Chlorthalidone page.
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