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Date of last update: 10/04/2017.

Forum Name: Neurology Topics

Question: dilantin residue in body ?

 jewelrylady - Wed Nov 05, 2008 7:04 pm

When an individual stops taking seizure meds.(Dilantin) does it take a while for it to leave the system ? If so, how long ? My son took it for many years and has been off it for 2 months with just one seizure. Sometimes he gets a light-headed feeling and cannot speak, although he hears what is going on around him. Could this be an absence seizure?
 John Kenyon, CNA - Mon Dec 08, 2008 11:09 pm

User avatar Hello -

The half-life of Dilantin is about 22 hours, with a rough residual presence of 42 hours. The numbers tend to be somewhat lower (shorter duration) in children. Since your son has been off the drug for 2 months there should be no residue of the drug present even in trace amounts.

The apparent seizure activity you describe sounds more like a focal or partial seizure rather than an absence seizure, since with the latter the patient rarely even realizes it's taken place, and so wouldn't be aware of what's going on around him nor remember hearing anything. It's more like a lost moment or a skip in time.

I hope this is helpful to you. Best of luck to you both and please follow up with us as needed.

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