What the FDA labels say about taking them together
Fosinopril/hydrochlorothiazide and triamterene
Fosinopril/hydrochlorothiazide's FDA label of April 28, 2024 names triamterene in its drug interactions section; triamterene's label does not name fosinopril/hydrochlorothiazide itself but warns about its class (ACE inhibitors, Thiazide diuretics). The fosinopril/hydrochlorothiazide label: “Potassium-sparing diuretics or potassium supplements can increase the risk of hyperkalemia.”
Check it at the source: the fosinopril/hydrochlorothiazide FDA label on DailyMed (effective April 28, 2024, Aurobindo Pharma Limited); the triamterene FDA label on DailyMed (effective December 5, 2024, Advanz Pharma (US) Corp.).
What does the fosinopril/hydrochlorothiazide label say about triamterene?
Fosinopril/hydrochlorothiazide label, drug interactionsPotassium-sparing diuretics (spironolactone, amiloride, triamterene, and others) or potassium supplements can increase the risk of hyperkalemia.
Source: FDA drug label (Fosinopril Sodium and Hydrochlorothiazide), Aurobindo Pharma Limited, effective April 28, 2024 (SPL set 35019655-9a30-4305-a262-936ad0e73071), via openFDA; the full label on DailyMed
What does the triamterene label say about fosinopril/hydrochlorothiazide?
Triamterene's label does not name fosinopril/hydrochlorothiazide itself; it warns about its class (ACE inhibitors, Thiazide diuretics):
Triamterene label, drug interactionsPotassium-sparing agents should be used with caution in conjunction with angiotensin-converting enzyme (ACE) inhibitors due to an increased risk of hyperkalemia.
Triamterene label, warnings and precautionsIf the ECG shows no widening of the QRS or arrhythmia in the presence of hyperkalemia, it is usually sufficient to discontinue Dyrenium (triamterene) and any potassium supplementation, and substitute a thiazide alone.
Source: FDA drug label (Dyrenium), Advanz Pharma (US) Corp., effective December 5, 2024 (SPL set ebb177c0-d45d-4443-a85a-e76bd9931a42), 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
| Fosinopril/hydrochlorothiazide | Triamterene | |
|---|---|---|
| Labeled for | High blood pressure | Heart failure, Edema (fluid retention) |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.634 per tablet 10-12.5 mg tablet | $5.98 per capsule 50 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