Hi There, Thank you for asking. The reason is that Zonigran is metabolized by a rout in the liver
that a substance which is found in grapefruit is metabolized. This causes a change in the plasma level of the medication you are using. This is not applied to other citrus fruits so you can freely eat other citrus fruits. Zonigran is a medication which alters the PH of your blood by excretion of acid and retaining of amonia. This helps to change the threshold for the seizure
and stabilize the neurons cell membrane. I wish you a seizure free life. If you do not have seizure for two years, the doctor may decrease or discontinue your medications. i wish you a good health.