Drug interactions
Chlorthalidone + Insulin nph
Severity: Moderate
Chlorthalidone and Insulin nph: 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
Chlorthalidone can impair glucose tolerance and raise blood glucose, which may reduce the effectiveness of insulin. Diabetic patients may need higher insulin doses.
What this interaction means in plain words
Chlorthalidone and Insulin nph 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.
Why it happens
Thiazide-type diuretics cause hypokalemia-related reduced insulin secretion and increased insulin resistance, opposing insulin action.
What to do
Monitor blood glucose when starting or changing chlorthalidone and adjust the insulin dose as needed. Keep potassium in the normal range.
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
Frequently asked questions
Can I take Chlorthalidone with Insulin nph?
MediHelp rates the interaction as moderate. Chlorthalidone and Insulin nph 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 can impair glucose tolerance and raise blood glucose, which may reduce the effectiveness of insulin. Diabetic patients may need higher insulin doses.
How serious is the interaction between Chlorthalidone and Insulin nph?
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 blood glucose when starting or changing chlorthalidone and adjust the insulin dose as needed. Keep potassium in the normal range.
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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