Obeticholic Acid + Dextromethorphan = Unknown or no reaction

Effect on Concentration

Obeticholic Acid
No change
Applies within class?
No
Dextromethorphan
Decrease
Applies within class?
No

Pharmacologic Effects

Obeticholic Acid
Effect
N/A
Applies within class?
No
Dextromethorphan
Effect
N/A
Applies within class?
No

Interaction History

N/A

Last Updated 20-Jul-2018

Summary

Sources

Obeticholic Acid versus Dextromethorphan ^

Study Design

In a fixed-sequence and 2-period study in n=19-24 healthy subjects were given a single oral dose of 30mg of dextromethorphan on day 1 and day 18. Obeticholic acid (OCA) 10mg or 25 mg daily alone was given for 17 days prior to the administration of the second dextromethorphan dose.

Study Results

Following multiple doses of OCA 10mg QD, AUC and Cmax of dextromethorphan decreased by 11% and 12% respectively. Following multiple doses of OCA 25mg QD, AUC and Cmax of dextromethorphan decreased by 11% and 17.4% respectively.

Study Conclusions

Per the investigators, the systemic exposures to dextromethorphan are small and thus no dose adjustment is needed when co-administering a CYP2D6 substrate with OCA.

References

Edwards JE, Eliot L, Parkinson A, Karan S, MacConell L. Assessment of pharmacokinetic interactions between obeticholic acid and caffeine, midazolam, warfarin, dextromethorphan, omeprazole, rosuvastatin, and digoxin in phase 1 studies in healthy subjects. Advances In Therapy. 2017; 9: 2120-2138.