Can thiazide diuretics be used in patients with a sulfa allergy?
Sulfonamide antibiotics are one of the most common causes of drug allergies.
However, there is minimal evidence of cross-reactivity between sulfonamide antibiotics and nonantibiotics, such as thiazide diuretics.
Available data suggest that cross-reactivity may be due to a susceptibility to allergic drug reactions in general, rather than a specific sulfa allergy.
Considerations before prescribing a thiazide in patients with a sulfa allergy include the nature and severity of the initial reaction, the type of medication implicated (antibiotic vs. nonantibiotic), and whether alternative treatments are available.
Loop diuretics are not alternatives to thiazide diuretics because they increase calcium excretion.