From the Guidelines
No, benazepril and Hydrochlorothiazide (HCTZ) is not a sulfa drug in the context of cross-reactivity with sulfonamide antimicrobials.
Rationale
- According to the study 1, Hydrochlorothiazide, a thiazide diuretic, is listed as a drug with no or weak evidence of cross-reactivity in patients with a history of a sulfonamide antimicrobial adverse reaction.
- The study 1 also notes that sulfonamide non-antimicrobials, such as thiazide diuretics, are structurally different from sulfonamide antimicrobials and have minimal concern for cross-reactivity.
- Key points to consider:
- Benazepril is an ACE inhibitor and is not a sulfonamide.
- Hydrochlorothiazide is a thiazide diuretic and is not a sulfonamide antimicrobial.
- The combination of benazepril and Hydrochlorothiazide is not a sulfa drug in the context of cross-reactivity with sulfonamide antimicrobials.
From the FDA Drug Label
Hydrochlorothiazide, USP is the 3,4-dihydro derivative of chlorothiazide. Its chemical name is 6-Chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1-dioxide. Benazeprilat, the active metabolite of benazepril, is a non-sulfhydryl angiotensin-converting enzyme inhibitor.
The combination of benazepril and Hydrochlorothiazide (HCTZ) does contain a sulfa drug, specifically Hydrochlorothiazide, which is a sulfonamide derivative.
- Key points:
From the Research
Benazepril and Hydrochlorothiazide (HCTZ) Composition
- Benazepril is a nonsulfhydryl ACE inhibitor prodrug, which is converted in vivo to its active form, benazeprilat 4
- Hydrochlorothiazide (HCTZ) is a diuretic, but its chemical structure does not contain a sulfa group, however, it is a sulfonamide derivative
Sulfa Drug Classification
- Sulfa drugs are a class of antimicrobials that contain the sulfonamide group, however, not all sulfonamide derivatives are classified as sulfa drugs
- Benazepril does not contain a sulfonamide group or a sulfa moiety, and is not classified as a sulfa drug 4
- Hydrochlorothiazide is a sulfonamide derivative, but it is not typically classified as a sulfa drug in the context of antimicrobial therapy, however, it may cause adverse reactions in patients with sulfa allergy 5
Clinical Use of Benazepril and HCTZ
- Benazepril and HCTZ are often used in combination to treat hypertension, and have been shown to be effective in reducing blood pressure in patients with mild to moderate hypertension 6, 7
- The combination of benazepril and HCTZ has been compared to other antihypertensive regimens, including benazepril plus amlodipine besylate, and has been shown to be effective in achieving blood pressure goals 5