Drug interactions
Atenolol-chlorthalidone + Trimethoprim
Severity: Moderate
Atenolol-chlorthalidone and Trimethoprim: 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
Trimethoprim can cause hyponatremia and hyperkalemia, and chlorthalidone also causes sodium loss. The combination raises the risk of significant hyponatremia, particularly in older adults or high-dose trimethoprim use.
What this interaction means in plain words
Atenolol-chlorthalidone and Trimethoprim 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.
Atenolol-chlorthalidone belongs to Cardiovascular; Trimethoprim belongs to Anti Bacterial.
Why it happens
Additive natriuresis from thiazide-like diuresis and trimethoprim's amiloride-like ENaC blockade.
What to do
Check serum sodium and potassium within the first several days of therapy. Stop or switch the antibiotic if marked electrolyte disturbance 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 Atenolol-chlorthalidone
Other interactions of Trimethoprim
Frequently asked questions
Can I take Atenolol-chlorthalidone with Trimethoprim?
MediHelp rates the interaction as moderate. Atenolol-chlorthalidone and Trimethoprim 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. Trimethoprim can cause hyponatremia and hyperkalemia, and chlorthalidone also causes sodium loss. The combination raises the risk of significant hyponatremia, particularly in older adults or high-dose trimethoprim use.
How serious is the interaction between Atenolol-chlorthalidone and Trimethoprim?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check serum sodium and potassium within the first several days of therapy. Stop or switch the antibiotic if marked electrolyte disturbance develops.
What other medicines interact with Atenolol-chlorthalidone?
MediHelp also lists interactions of Atenolol-chlorthalidone with, for example, Acebutolol, Aldesleukin, Amiodarone. The full list is on the Atenolol-chlorthalidone page.
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