Drug interactions
Hydrochlorothiazide + Tizanidine
Severity: Moderate
Hydrochlorothiazide and Tizanidine: 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
Tizanidine can lower blood pressure, and hydrochlorothiazide adds to this through diuresis and volume reduction. The combination may produce excessive hypotension or orthostatic symptoms, especially in older patients.
What this interaction means in plain words
Hydrochlorothiazide and Tizanidine 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.
Hydrochlorothiazide belongs to Cardiovascular; Tizanidine belongs to Musculoskeletal.
Why it happens
Additive pharmacodynamic hypotension from central alpha-2 agonism and thiazide-induced volume depletion.
What to do
Monitor blood pressure and orthostatic symptoms when starting or adjusting either drug. Start tizanidine at a low dose and reduce the diuretic if 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 Tizanidine
- Ciprofloxacin + Tizanidine Contraindicated
- Fluvoxamine + Tizanidine Contraindicated
- Pefloxacin + Tizanidine Contraindicated
- Pipemidic acid + Tizanidine Contraindicated
- Benzhydrocodone / acetaminophen + Tizanidine Major
- Brexanolone + Tizanidine Major
Other interactions of Hydrochlorothiazide
Frequently asked questions
Can I take Hydrochlorothiazide with Tizanidine?
MediHelp rates the interaction as moderate. Hydrochlorothiazide and Tizanidine 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. Tizanidine can lower blood pressure, and hydrochlorothiazide adds to this through diuresis and volume reduction. The combination may produce excessive hypotension or orthostatic symptoms, especially in older patients.
How serious is the interaction between Hydrochlorothiazide and Tizanidine?
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 and orthostatic symptoms when starting or adjusting either drug. Start tizanidine at a low dose and reduce the diuretic if hypotension occurs.
What other medicines interact with Tizanidine?
MediHelp also lists interactions of Tizanidine with, for example, Ciprofloxacin, Fluvoxamine, Pefloxacin. The full list is on the Tizanidine page.
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