The most common generalised seizure is of the tonic-clonic type (grand mal). This kind of seizure can start as a partial seizure with secondary generalisation or directly as a primary generalised seizure.
The mechanism of the seizure begins with the abnormal channel function, proceeds with the loss of inhibitory control and finally spreads over different brain region. The loss of GABA inhibition is characteristic for the tonic-clonic seizure.
At the time that the GABA inhibition is restoring excitation starts to oscillate with the inhibitory moments. During this period of excitation and inhibition the patient displays shaking movements (when the motor cortex is involved; the clonic phase). The seizure ends when the GABA-ergic inhibition completely restores and overrules the excitations.
Possible causes of seizures are the following, EXCEPT: