What the FDA labels say about taking them together
Hydrochlorothiazide/spironolactone and indomethacin
Hydrochlorothiazide/spironolactone's FDA label of March 11, 2026 names indomethacin in its drug interactions section; indomethacin's label does not name hydrochlorothiazide/spironolactone itself but warns about its class (Aldosterone antagonists, Thiazide diuretics). The hydrochlorothiazide/spironolactone label: “Combination of NSAIDs, e.g., indomethacin, with potassium-sparing diuretics has been associated with severe hyperkalemia.”
Check it at the source: the hydrochlorothiazide/spironolactone FDA label on DailyMed (effective March 11, 2026, Mylan Pharmaceuticals Inc.); the indomethacin FDA label on DailyMed (effective December 19, 2025, Glenmark Pharmaceuticals Inc., USA).
What does the hydrochlorothiazide/spironolactone label say about indomethacin?
Hydrochlorothiazide/spironolactone label, drug interactionsCombination of NSAIDs, e.g., indomethacin, with potassium-sparing diuretics has been associated with severe hyperkalemia.
Hydrochlorothiazide/spironolactone label, warningsSpironolactone, when used with ACE inhibitors or indomethacin, even in the presence of a diuretic, has been associated with severe hyperkalemia.
Source: FDA drug label (Spironolactone and Hydrochlorothiazide), Mylan Pharmaceuticals Inc., effective March 11, 2026 (SPL set 0c8c973f-13a2-4883-8316-4006398e2931), via openFDA; the full label on DailyMed
What does the indomethacin label say about hydrochlorothiazide/spironolactone?
Indomethacin's label does not name hydrochlorothiazide/spironolactone itself; it warns about its class (Aldosterone antagonists, Thiazide diuretics):
Indomethacin label, drug interactionsClinical studies, as well as post-marketing observations, showed that NSAIDs reduced the natriuretic effect of loop diuretics (e.g., furosemide) and thiazide diuretics in some patients.
Indomethacin label, drug interactionsBoth indomethacin capsules and potassium-sparing diuretics may be associated with increased serum potassium levels.
Source: FDA drug label (Indomethacin), Glenmark Pharmaceuticals Inc., USA, effective December 19, 2025 (SPL set f7ed39e2-5431-4e47-935c-c7441d058f94), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Hydrochlorothiazide/spironolactone | Indomethacin | |
|---|---|---|
| Labeled for | Heart failure, Edema (fluid retention), High blood pressure | Rheumatoid arthritis, Osteoarthritis |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.483 per tablet 25-25 tablet | $0.210 per capsule 75 mg capsule |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once