Terbinafine and Buproprion Association Induced Seizure (UMSLE Step 2 CK)

 

Seizure Activity & Bupropion – Easy Explanation

✔ What is Bupropion?

• An antidepressant used for bipolar disorder (if mood stabilizers don’t work).

• Works by blocking the reuptake of dopamine and norepinephrine (increasing their levels).

✔ Why Can It Cause Seizures?

• Bupropion lowers the seizure threshold, making seizures more likely.

• It is metabolized by CYP-2D6 (a liver enzyme).

✔ What Happens When Taken with Terbinafine?

• Terbinafine inhibits CYP-2D6, which increases bupropion levels in the body.

• This leads to a higher risk of medication-induced seizures.

✔ What Do Medication-Induced Seizures Look Like?

• Usually generalized tonic-clonic seizures (shaking, loss of consciousness).

• Rarely causes absence seizures (brief staring episodes).

✔ Management

• Switch terbinafine to a topical antifungal (if treating nail fungus).

• Switch bupropion to another antidepressant that doesn’t lower the seizure threshold.

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Why the Other Options Are Incorrect?

❌ Catatonic Episode (A)

• Marked by inability to move or speak (or repetitive movements).

• Lasts days, not just seconds to minutes.

❌ Glioblastoma Multiforme (B)

• Aggressive brain tumor that can cause seizures.

• Tumor-related seizures are usually focal, not generalized.

❌ Rapid Cycling Bipolar Disorder (C)

• Defined as ≥4 mood episodes per year (mania or depression).

• Doesn’t cause staring spells like absence seizures.

❌ Transient Ischemic Attack (E)

• Brief stroke-like symptoms that last minutes to hours.

• Causes focal neurologic deficits, not generalized seizures.

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Key Takeaways

✔ Bupropion lowers seizure threshold and is metabolized by CYP-2D6.
✔ Terbinafine inhibits CYP-2D6, increasing bupropion levels and seizure risk.
✔ Seizures from medications are usually generalized tonic-clonic.
✔ Treatment: Switch terbinafine to a topical antifungal or change the antidepressant.

So the Answer is Seizure activity