Drug interactions
Citalopram + Hydrochlorothiazide
Severity: Moderate
Citalopram and Hydrochlorothiazide: 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
Both thiazides and SSRIs can cause hyponatraemia, especially in older adults, and the risk is additive. Thiazide-related hypokalaemia and hypomagnesaemia may also add to the QT risk of citalopram.
What this interaction means in plain words
Citalopram and Hydrochlorothiazide 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.
Citalopram belongs to Central Nervous System; Hydrochlorothiazide belongs to Cardiovascular.
Why it happens
Additive sodium depletion and SIADH-type effect, with electrolyte disturbances adding to QT prolongation.
What to do
Check sodium, potassium and magnesium at baseline and after starting, particularly in older patients. Watch for confusion, falls or seizures and correct electrolytes.
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 Hydrochlorothiazide
Other interactions of Citalopram
- Cisapride + Citalopram Contraindicated
- Citalopram + Dronedarone Contraindicated
- Citalopram + Escitalopram Contraindicated
- Citalopram + Isocarboxazid Contraindicated
- Citalopram + Methylene blue Contraindicated
- Citalopram + Phenelzine Contraindicated
Frequently asked questions
Can I take Citalopram with Hydrochlorothiazide?
MediHelp rates the interaction as moderate. Citalopram and Hydrochlorothiazide 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. Both thiazides and SSRIs can cause hyponatraemia, especially in older adults, and the risk is additive. Thiazide-related hypokalaemia and hypomagnesaemia may also add to the QT risk of citalopram.
How serious is the interaction between Citalopram and Hydrochlorothiazide?
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 sodium, potassium and magnesium at baseline and after starting, particularly in older patients. Watch for confusion, falls or seizures and correct electrolytes.
What other medicines interact with Hydrochlorothiazide?
MediHelp also lists interactions of Hydrochlorothiazide with, for example, Dofetilide, Amifostine, Amiodarone. The full list is on the Hydrochlorothiazide page.
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