Hydrochlorothiazide/Triamterene and Lisinopril Interaction
Drug interaction information between Hydrochlorothiazide/Triamterene and Lisinopril.
Hydrochlorothiazide/Triamterene and Lisinopril have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Hydrochlorothiazide/Triamterene and Lisinopril. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Taking these two types of blood pressure medicines together can cause your blood pressure to drop too low, especially when you first start. This can make you feel very dizzy or lightheaded.
What To Do
Your doctor may start you on a lower dose of the new medicine to keep your blood pressure steady. Be sure to stand up slowly and tell your doctor if you feel faint.
FDA Label Information
Drug Interactions Lisinopril Hypotension - Patients on Diuretic Therapy: Patients on diuretics and especially those in whom diuretic therapy was recently instituted, may occasionally experience an excessive reduction of blood pressure after initiation of therapy with lisinopril. The possibility of hypotensive effects with lisinopril can be minimized by either discontinuing the diuretic or increasing the salt intake prior to initiation of treatment with lisinopril. If it is necessary to continue the diuretic, initiate therapy with lisinopril at a dose of 5 mg daily, and provide close...
Hydrochlorothiazide/Triamterene Also Interacts With
- Hydrochlorothiazide major
- Aliskiren major
- Losartan minor
- Spironolactone minor
- Propranolol minor
Lisinopril Also Interacts With
- Hydrochlorothiazide major
- Aliskiren major
- Losartan minor
- Spironolactone minor
- Propranolol minor
Frequently Asked Questions
Can I take Hydrochlorothiazide/Triamterene and Lisinopril together?
This is a minor interaction. Your doctor may start you on a lower dose of the new medicine to keep your blood pressure steady. Be sure to stand up slowly and tell your doctor if you feel faint.
How serious is the interaction between Hydrochlorothiazide/Triamterene and Lisinopril?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Hydrochlorothiazide/Triamterene and Lisinopril interact?
Taking these two types of blood pressure medicines together can cause your blood pressure to drop too low, especially when you first start. This can make you feel very dizzy or lightheaded.
Understanding the Hydrochlorothiazide/Triamterene and Lisinopril Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Hydrochlorothiazide/Triamterene belongs to the Thiazide / Potassium-Sparing Diuretic Combination class and Lisinopril belongs to the ACE Inhibitor class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Taking these two types of blood pressure medicines together can cause your blood pressure to drop too low, especially when you first start. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Hydrochlorothiazide/Triamterene has 13 total documented interactions on file in this dataset, and Lisinopril has 15. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor may start you on a lower dose of the new medicine to keep your blood pressure steady. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Hydrochlorothiazide/Triamterene or Lisinopril based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.