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, which is Hydrochlorothiazide, as it contains a sulfonamide group in its chemical structure.
- Key points:
- Hydrochlorothiazide is a sulfonamide derivative.
- Benazepril does not contain a sulfa group.
- The combination of benazepril and HCTZ contains a sulfa drug due to the presence of HCTZ 2.
From the Research
Benazepril and Hydrochlorothiazide (HCTZ) Classification
- Benazepril is an angiotensin-converting enzyme inhibitor, and its classification as a sulfa drug is not applicable 3, 4, 5, 6.
- Hydrochlorothiazide (HCTZ) is a sulfonamide-containing drug, which is a type of sulfa drug 7.
Key Points
- HCTZ is a sulfa drug due to its sulfonamide content, which can cause allergic reactions in some individuals 7.
- Benazepril and HCTZ are often used in combination to treat hypertension, and their efficacy and safety have been studied in various clinical trials 3, 4, 5, 6.
- The combination of benazepril and HCTZ has been shown to be effective in reducing blood pressure and improving cardiovascular outcomes in patients with hypertension 4, 5.
Allergic Reactions
- Patients with a history of allergic reactions to sulfonamide drugs may be at risk of experiencing hypersensitivity reactions to HCTZ 7.
- The mechanism of allergic reactions to HCTZ is not fully understood, but it is thought to be related to a predisposition to drug allergies rather than cross-sensitivity between sulfonamide antibiotics and nonantibiotic drugs 7.