Does Isoniazid Interact with Dexamethasone Intensol?
Isoniazid and Dexamethasone Intensol have a moderate drug interaction according to U.S. FDA drug labeling data. Serum concentrations of isoniazid may be decreased by dexamethasone. The mechanism involves increased isoniazid clearance. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Moderate
- Isoniazid Class
- Antimycobacterial
- Dexamethasone Intensol Class
- Corticosteroid
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Isoniazid and Dexamethasone Intensol occurs because increased isoniazid clearance. Clinically, this means serum concentrations of isoniazid may be decreased by dexamethasone. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Isoniazid and your doctor is considering prescribing Dexamethasone Intensol (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider