Drug General Information (ID: DDI58ZJKED)
Drug Name			Posaconazole		Drug Info		Dexlansoprazole		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antifungal Agents				Proton Pump Inhibitors
Structure

Mechanism of Posaconazole-Dexlansoprazole Interaction (Severity Level: Moderate)
Altered gastric pH Click to Show/Hide Mechanism Graph
Drug Name		Posaconazole				Dexlansoprazole
Mechanism		Gastric pH sensitive				Gastric alkalinizer
Key Mechanism Factor 1
		Factor Name		Gastric pH
		Factor Description		The normal pH range of gastric acid is between 1.5 and 3.5 and is highly acidic, consisting mainly of hydrochloric acid. Changes in the pH of the stomach can alter the absorption of drugs.
Mechanism Description		Decreased absorption of Posaconazole due to altered gastric pH caused by Dexlansoprazole

Recommended Action
Management		Concomitant use of posaconazole oral suspension with proton pump inhibitors should generally be avoided. If possible, prescribers may consider suspending the PPI until completion of posaconazole therapy, or substituting an antifungal agent like fluconazole or voriconazole whose absorption is not affected by stomach pH. Delayed-release tablets of posaconazole may be used with PPIs, as no pharmacokinetic interaction has been demonstrated with esomeprazole.

References
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6	Product Information. Noxafil (posaconazole). Schering-Plough Corporation, Kenilworth, NJ.
7	Shields RK, Clancy CJ, Vadnerkar A, et al "Posaconzaole serum concentrations among cardiothoracic transplant recipients: factors impacting trough levels and correlation with clinical response to therapy." Antimicrob Agents Chemother 55 (2011): 1308-11. [PMID: 21189337]
8	Vaes M, Hites M, Cotton F, et al. "Therapeutic drug monitoring of posaconazole in patients with acute myeloid leukemia or myelodysplasic syndrome." Antimicrob Agents Chemother 56 (2012): 6298-303. [PMID: 23027198]
9	Walravens J, Brouwers J, Spriet I, Tack J, Annaert P, Augustijns P "Effect of pH and Comedication on Gastrointestinal Absorption of Posaconazole: Monitoring of Intraluminal and Plasma Drug Concentrations." Clin Pharmacokinet 50 (2011): 725-34. [PMID: 21973269]
10	Krishna G, Moton A, Ma L, Malavade D, Medlock M, McLeod J "Effect of gastric pH, dosing regimen and prandial state, food and meal timing relative to dose, and gastro-intestinal motility on absorption and pharmacokinetics of the antifungal posaconazole." 18th European Congress of Clinical Microbiology and Infectious Diseases April (2008): 20.