Oral Absorption of an Azole for Antifungal Therapy in a Patient with Hypochlorhydria or Achlorhydria

 

Azoles that may have reduced absorption if gastric pH is too high:

(1) itraconazole

(2) ketoconazole

 

Clinical findings of decreased absorption due to elevated gastric pH:

(1) poor clinical response or lower than expected serum levels

(2) exclusion of noncompliance and drug resistance

(3) hypochlorhydria or achlorhydria due to

(3a) underlying disease (atrophic gastritis, etc.)

(3b) pharmacologic depression of acid production (H2 inhibitor, proton pump inhibitor)

(3c) excess ingestion of buffer or antacids

 

Lange et al found that ingestion of a cola or other acidic beverage when taking an azole can significantly increase absorption.