Product information and disease description Product description Product information Drug/Drug, drug/disease interactions

Effects of other drugs on tiratricol

7 evidence topics · 3 sources

Clinical drug interaction studies

“Many drugs can exert effects on thyroid hormone pharmacokinetics and may alter the therapeutic response. No clinical drug interaction studies have been conducted with EMCITATE.” (opens the prescribing information at this quote)

Drugs that may affect tiratricol absorption

Drug or drug class	Effect	Clinical recommendation
Bile acid sequestrants and ion exchange resins	“Bile acid sequestrants and ion exchange resins decrease thyroid hormone exposure by binding and delaying or preventing absorption.”	“Avoid concomitant use of bile acid sequestrants and ion exchange resins with EMCITATE.”
Iron and calcium supplements	“Iron and calcium may interfere with the absorption of tiratricol.”	“If concomitant use of iron or calcium supplements is necessary, administer iron or calcium supplements consistently at the same time each day relative to EMCITATE dosing.”
Proton pump inhibitors	“Changes in gastric pH associated with PPI therapy may increase the absorption of tiratricol.”	“Serum concentrations of T3 should be monitored and dose adjustments of EMCITATE considered when initiating, modifying or discontinuing PPI treatment.”

Drugs that may alter plasma binding of T3

Drug or drug class	Effect	Clinical recommendation
Oral estrogen-containing products	“These drugs may increase serum thyroxine-binding globulin (TBG) concentration and increase total T3 serum levels.”	“Monitor clinical symptoms and evaluate free T3 levels.”
Anabolic steroids and glucocorticoids	“These drugs may decrease serum TBG concentration and decrease total T3 serum levels.”	“Monitor clinical symptoms and evaluate free T3 levels.”
Salicylates, more than 2 g/day	“Salicylates inhibit binding of T3 to TBG and transthyretin and may inhibit binding of tiratricol to transthyretin.”	“Monitor clinical symptoms and evaluate free T3 levels.”

Drugs that may increase hepatic metabolism of tiratricol

Drug or drug class	Effect	Clinical recommendation
Drugs that increase hepatic drug-metabolizing enzyme activity	“Administration of drugs that increase hepatic drug-metabolizing enzyme activity may increase the hepatic degradation of thyroid hormones and tiratricol.”	“Serum concentrations of thyroid hormones should be monitored and dose adjustments of EMCITATE considered when initiating, titrating or discontinuing treatment with enzyme inducing agents.”

In vitro transporter substrate studies

“Tiratricol is not a substrate for P-gp, BCRP, OAT1, OAT3, OCT1, OCT2, OATP1B1, OATP1B3, MATE1 or MATE2-K.” (opens the prescribing information at this quote)

Drugs that may affect tiratricol: European summary of product characteristics

Drug or drug class	Statement in the summary of product characteristics
Antacids, charcoal, calcium, cationic resins, iron, and sucralfate	“Antacids, charcoal, calcium, cationic resins (e.g. cholestyramine), iron, sucralphate, and other gastrointestinal agents may interfere with the gastrointestinal absorption of tiratricol. These treatments should be taken before or after tiratricol (more than 2 hours before or after if possible). In the case of cholestyramine, tiratricol should be taken 1 hour before or 4 hours after the resin dose.”
Proton pump inhibitors	“Co-administration with PPIs may cause a decrease in the absorption of the thyroid hormones, due to the increase of the intragastric pH caused by PPIs such as omeprazole, esomeprazole, pantoprazole, rabeprazole and lansoprazole. Serum concentrations of T3 should be monitored and dose adjustment of tiratricol considered when initiating, changing or discontinuing PPI treatment.”
Sevelamer	“Sevelamer may decrease the concentration of thyroid hormones and result in reduced efficacy of tiratricol. Sevelamer should be taken more than 2 hours before or after administration of tiratricol.”
Enzyme inducers, including antiepileptics	“Medicinal products that can induce the enzyme system in the liver, such as barbiturates, phenytoin carbamazepine, rifabutin, rifampicin or products containing St. John’s wort (Hypericum perforatum) may increase the hepatic clearance of tiratricol.”
Antimalarials	“Concomitant use of tiratricol and antimalarial medicinal products (chloroquine, proguanil) may cause clinical hypothyroidism.”
Non-contraceptive oestrogens	“Non-contraceptive oestrogen and oestrogen containing products (including hormone replacement therapy) may increase the requirement of tiratricol treatment dose.”
Orlistat	“Orlistat may decrease tiratricol absorption which may result in hypothyroidism (changes in thyroid function should be monitored).”

Proton pump inhibitors: published management recommendations

“Patients should be monitored for signs of gastroesophageal reflux disease and may benefit from treatment with proton pump inhibitors (PPIs).” (opens the source at this quote in a new tab)
“While this finding is debated and has not been replicated upon coadministration of PPIs and TRIAC, additional monitoring of TH levels is recommended when the dose of either is initiated, adjusted, or discontinued.” (opens the source at this quote in a new tab)