Drug interactions
Felbamate + Tolbutamide
Severity: Minor
Felbamate and Tolbutamide: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Felbamate inhibits CYP2C19 and may affect other hepatic pathways, and it could raise tolbutamide exposure, a CYP2C9 substrate. This might increase the risk of hypoglycemia, though documented evidence is limited.
What this interaction means in plain words
Felbamate and Tolbutamide have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Felbamate belongs to Central Nervous System; Tolbutamide belongs to Endocrine.
Why it happens
Felbamate may inhibit CYP2C9-mediated tolbutamide metabolism, decreasing its clearance.
What to do
Monitor blood glucose when felbamate is started or stopped and lower the tolbutamide dose if hypoglycemia occurs.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Tolbutamide
- Glyburide-metformin + Tolbutamide Major
- Insulin degludec-liraglutide + Tolbutamide Major
- Aceclofenac + Tolbutamide Moderate
- Acemetacin + Tolbutamide Moderate
- Acetylsalicylic acid + Tolbutamide Moderate
- Albiglutide + Tolbutamide Moderate
Other interactions of Felbamate
- Felbamate + Ulipristal Major
- Amisulpride + Felbamate Moderate
- Amitriptyline + Felbamate Moderate
- Apalutamide + Felbamate Moderate
- Asenapine + Felbamate Moderate
- Bosentan + Felbamate Moderate
Frequently asked questions
Can I take Felbamate with Tolbutamide?
MediHelp rates the interaction as minor. Felbamate and Tolbutamide have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Felbamate inhibits CYP2C19 and may affect other hepatic pathways, and it could raise tolbutamide exposure, a CYP2C9 substrate. This might increase the risk of hypoglycemia, though documented evidence is limited.
How serious is the interaction between Felbamate and Tolbutamide?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood glucose when felbamate is started or stopped and lower the tolbutamide dose if hypoglycemia occurs.
What other medicines interact with Tolbutamide?
MediHelp also lists interactions of Tolbutamide with, for example, Glyburide-metformin, Insulin degludec-liraglutide, Aceclofenac. The full list is on the Tolbutamide page.
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