Details of Drug-Drug Interaction
| Drug General Information (ID: DDIJ0WXCRI) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Drug Name | Liotrix | Drug Info | Ferrous fumarate | Drug Info | |||||
| Drug Type | Small molecule | Small molecule | |||||||
| Therapeutic Class | Thyroid Drugs | Iron Supplement | |||||||
| Structure | |||||||||
| Mechanism of Liotrix-Ferrous fumarate Interaction (Severity Level: Moderate) | |||||||||
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| Complex formation Click to Show/Hide Mechanism Graph | |||||||||
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| Drug Name | Liotrix | Ferrous fumarate | |||||||
| Mechanism | Binds to polyvalent cations | Polyvalent cations | |||||||
| 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 |
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| Recommended Action | |||||||||
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| Management | Some experts recommend separating the times of administration of levothyroxine and iron-containing preparations by at least 2 to 4 hours. Monitoring of serum TSH levels is recommended. Patients with gastrointestinal or malabsorption disorders may be at a greater risk of developing clinical or subclinical hypothyroidism due to this interaction. | ||||||||
| References | |||||||||||||||||||
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| 1 | Campbell NR, Hasinoff BB, Stalts H, Rao B, Wong NC "Ferrous sulfate reduces thyroxine efficacy in patients with hypothyroidism." Ann Intern Med 117 (1992): 1010-3. [PMID: 1443969] | ||||||||||||||||||