Drug interactions
Hydrochlorothiazide-olmesartan + Olanzapine / samidorphan
Severity: Moderate
Hydrochlorothiazide-olmesartan and Olanzapine / samidorphan: 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
Olanzapine can cause orthostatic hypotension, which may add to the effect of antihypertensive drugs. Patients may experience dizziness, syncope or falls, especially early in treatment or after dose increases.
What this interaction means in plain words
Hydrochlorothiazide-olmesartan and Olanzapine / samidorphan 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
Additive hypotension from olanzapine alpha-1 adrenergic blockade combined with the diuretic and angiotensin receptor blocker.
What to do
Monitor blood pressure, including orthostatic readings, when starting or titrating olanzapine. Reduce the antihypertensive dose if symptomatic hypotension occurs.
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-olmesartan
- Aliskiren + Hydrochlorothiazide-olmesartan Contraindicated
- Dofetilide + Hydrochlorothiazide-olmesartan Contraindicated
- Hydrochlorothiazide-olmesartan + Sparsentan Contraindicated
- Acemetacin + Hydrochlorothiazide-olmesartan Major
- Amifostine + Hydrochlorothiazide-olmesartan Major
- Amiloride + Hydrochlorothiazide-olmesartan Major
Frequently asked questions
Can I take Hydrochlorothiazide-olmesartan with Olanzapine / samidorphan?
MediHelp rates the interaction as moderate. Hydrochlorothiazide-olmesartan and Olanzapine / samidorphan 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. Olanzapine can cause orthostatic hypotension, which may add to the effect of antihypertensive drugs. Patients may experience dizziness, syncope or falls, especially early in treatment or after dose increases.
How serious is the interaction between Hydrochlorothiazide-olmesartan and Olanzapine / samidorphan?
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 pressure, including orthostatic readings, when starting or titrating olanzapine. Reduce the antihypertensive dose if symptomatic hypotension occurs.
What other medicines interact with Hydrochlorothiazide-olmesartan?
MediHelp also lists interactions of Hydrochlorothiazide-olmesartan with, for example, Aliskiren, Dofetilide, Sparsentan. The full list is on the Hydrochlorothiazide-olmesartan page.
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