What the FDA labels say about taking them together
Captopril and triamterene
Captopril's FDA label of February 6, 2026 names triamterene in its drug interactions section; triamterene's label does not name captopril itself but warns about its class (ACE inhibitors). The captopril label: “Potassium-sparing diuretics such as spironolactone, triamterene, or amiloride, or potassium supplements should be given only for documented hypokalemia, and then with caution, since they may lead to a significant …”
Check it at the source: the captopril FDA label on DailyMed (effective February 6, 2026, AiPing Pharmaceutical, Inc.); the triamterene FDA label on DailyMed (effective December 5, 2024, Advanz Pharma (US) Corp.).
What does the captopril label say about triamterene?
Captopril label, drug interactionsPotassium-sparing diuretics such as spironolactone, triamterene, or amiloride, or potassium supplements should be given only for documented hypokalemia, and then with caution, since they may lead to a significant increase of serum potassium.
Source: FDA drug label (Captopril), AiPing Pharmaceutical, Inc., effective February 6, 2026 (SPL set 3b789f16-b291-4012-be39-af3beec3ff9a), via openFDA; the full label on DailyMed
What does the triamterene label say about captopril?
Triamterene's label does not name captopril itself; it warns about its class (ACE inhibitors):
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.
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
| Captopril | Triamterene | |
|---|---|---|
| Labeled for | High blood pressure, Heart failure, Chronic kidney disease | Heart failure, Edema (fluid retention) |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.228 per tablet 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