Drug General Information (ID: DDIS62QTEH)
Drug Name			Tolevamer		Drug Info		Thyroid, porcine		Drug Info
Drug Type		Small molecule				Hormones
Therapeutic Class		Potassium-Binding Resin				Thyroid Drugs

Mechanism of Tolevamer-Thyroid, porcine Interaction (Severity Level: Moderate)
Complex formation Click to Show/Hide Mechanism Graph
Drug Name		Tolevamer				Thyroid, porcine
Mechanism		Cation exchange resin/polymer				Binds to cation exchange resin/polymer
Key Mechanism Factor 1
		Factor Name		Chelation
		Factor Description		Chelation is a direct drug interaction that usually involves the formation of dimers or trimers, resulting in larger complexes and poorer absorption.
Mechanism Description		Decreased absorption of Tolevamer due to formation of complexes caused by Thyroid, porcine

Recommended Action
Management		Thyroid hormone preparations and ion-exchange resins should be administered at least 4 hours apart. Close clinical and laboratory monitoring of thyroid function is recommended during coadministration, since adjusting the dosing interval may not completely prevent the interaction.

References
1	McLean M, Kirkwood I, Epstein M, Jones B, Hall C "Cation-exchange resin and inhibition of intestinal absorption of thyroxine." Lancet 34 (1993): 1286. [PMID: 8098431]
2	Product Information. Kayexalate (sodium polystyrene sulfonate). Sanofi Winthrop Pharmaceuticals, New York, NY.
3	Product Information. Synthroid (levothyroxine). Abbott Pharmaceutical, Abbott Park, IL.