Drug interactions
Fosphenytoin + Linagliptin
Severity: Moderate
Fosphenytoin and Linagliptin: moderate 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
Fosphenytoin is converted to phenytoin, a CYP3A4 and P-gp inducer, which can lower linagliptin concentrations. This may reduce the glucose-lowering effect with long-term co-administration, as seen with other strong inducers such as rifampin.
What this interaction means in plain words
Fosphenytoin and Linagliptin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Fosphenytoin belongs to Central Nervous System; Linagliptin belongs to Endocrine.
Why it happens
Induction of CYP3A4 and P-glycoprotein by phenytoin increases linagliptin clearance and reduces exposure.
What to do
Monitor glycemic control and consider an alternative antidiabetic agent that is not affected by inducers if control is inadequate.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Linagliptin
- Alogliptin-pioglitazone + Linagliptin Moderate
- Amlodipine-benazepril + Linagliptin Moderate
- Amobarbital + Linagliptin Moderate
- Apalutamide + Linagliptin Moderate
- Benazepril + Linagliptin Moderate
- Bexarotene + Linagliptin Moderate
Other interactions of Fosphenytoin
- Dronedarone + Fosphenytoin Contraindicated
- Fosphenytoin + Ledipasvir-sofosbuvir Contraindicated
- Fosphenytoin + Lorlatinib Contraindicated
- Fosphenytoin + Lurasidone Contraindicated
- Fosphenytoin + Ranolazine Contraindicated
- Fosphenytoin + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
Frequently asked questions
Can I take Fosphenytoin with Linagliptin?
MediHelp rates the interaction as moderate. Fosphenytoin and Linagliptin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Fosphenytoin is converted to phenytoin, a CYP3A4 and P-gp inducer, which can lower linagliptin concentrations. This may reduce the glucose-lowering effect with long-term co-administration, as seen with other strong inducers such as rifampin.
How serious is the interaction between Fosphenytoin and Linagliptin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor glycemic control and consider an alternative antidiabetic agent that is not affected by inducers if control is inadequate.
What other medicines interact with Linagliptin?
MediHelp also lists interactions of Linagliptin with, for example, Alogliptin-pioglitazone, Amlodipine-benazepril, Amobarbital. The full list is on the Linagliptin page.
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