First seizure

[buddyrhonda]

What causes someone to have a weak leg after having an epileptic seizure (grand mal) for the first time?

[Godofredo MD]

Hi.

The period of transient weakness/paralysis that occurs after a seizure is called Todd's paralysis.  The paralysis is generally experienced on one side of the body and usually resolves within 24-48 hours. The etiology of this condition is not known. Treatment is only symptomatic as the weakness/paralysis resolves quickly.

However, it is essential to  to distinguish the occurrence of Todd's paralysis from a stroke, which would require different and emergent treatment.

Hope this helps.

[Caliber2005]

Hi,
How are you feeling now?
Did you have any other symptoms after the first event?
If during the seizure, if you have suffered any trauma to nerve supplying the lower limb it can cause weak leg.
If during the seizure, you have suffered trauma to part of brain having motor neurons of lower leg, then it can cause weakness.
How are the reflexes in that leg?
Has it been evaluated by a neurologist?
Are you been treated by neurologist? If yes, then what he has to say about this?
I think you should consult neurologist if symptoms are persisting at earliest.