Drug interactions
Hydrochlorothiazide + Magnesium hydroxide
Severity: Minor
Hydrochlorothiazide and Magnesium hydroxide: minor 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
Thiazide diuretics increase urinary magnesium loss and can lower serum magnesium over time. Occasional magnesium hydroxide as an antacid or laxative is unlikely to be affected in a meaningful way, and the effect is clinically small.
What this interaction means in plain words
Hydrochlorothiazide and Magnesium hydroxide have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Hydrochlorothiazide belongs to Cardiovascular; Magnesium hydroxide belongs to Gastrointestinal Tract.
Why it happens
Thiazides reduce renal magnesium reabsorption, increasing urinary magnesium excretion.
What to do
No action is needed for occasional use. In long-term thiazide therapy, check serum magnesium periodically and supplement if hypomagnesemia develops.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Magnesium hydroxide
Other interactions of Hydrochlorothiazide
Frequently asked questions
Can I take Hydrochlorothiazide with Magnesium hydroxide?
MediHelp rates the interaction as minor. Hydrochlorothiazide and Magnesium hydroxide have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Thiazide diuretics increase urinary magnesium loss and can lower serum magnesium over time. Occasional magnesium hydroxide as an antacid or laxative is unlikely to be affected in a meaningful way, and the effect is clinically small.
How serious is the interaction between Hydrochlorothiazide and Magnesium hydroxide?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No action is needed for occasional use. In long-term thiazide therapy, check serum magnesium periodically and supplement if hypomagnesemia develops.
What other medicines interact with Magnesium hydroxide?
MediHelp also lists interactions of Magnesium hydroxide with, for example, Ciprofloxacin, Dolutegravir, Gemifloxacin. The full list is on the Magnesium hydroxide page.
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