Drug General Information (ID: DDIZR8K3J9)
Drug Name			Sodium bicarbonate		Drug Info		Selpercatinib		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antidiarrheals				Antineoplastics
Structure

Mechanism of Sodium bicarbonate-Selpercatinib Interaction (Severity Level: Major)
Altered gastric pH Click to Show/Hide Mechanism Graph
Drug Name		Sodium bicarbonate				Selpercatinib
Mechanism		Gastric alkalinizer				Gastric pH sensitive
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 Selpercatinib due to altered gastric pH caused by Sodium bicarbonate

Recommended Action
Management		Concomitant use of selpercatinib with locally-acting antacids or other agents with acid neutralizing or reducing effects should generally be avoided. If coadministration is required, the manufacturer recommends taking selpercatinib 2 hours before or 2 hours after the antacid.

References
1	Product Information. Retevmo (selpercatinib). Lilly, Eli and Company, Indianapolis, IN.