About one in four autistic individuals begin to have seizures during puberty. The exact reason for the onset of seizures is not known, but it is likely that the seizure activity may be due to hormonal changes in the body. Sometimes these seizures are noticeable, (i.e., associated with convulsions); but for many, they are small, subclinical seizures, and are typically not detected by simple observation.

Some possible signs of subclinical seizure activity include:

exhibiting behavior problems, such as aggression, self-injury, and severe tantrumming;
making little or no academic gains after doing well during childhood and pre-teen years;
and/or losing some behavioral and/or cognitive gains.
Personally, I have known a few autistic individuals who were considered high-functioning prior to puberty. During puberty, they experienced seizures which were not treated. By their late teens, they were considered, however, as low functioning.
Some parents have an EEG performed to see if their child shows any seizure activity. However, even if the EEG does not detect abnormal activity during the testing period, one cannot conclude that the person does not have seizures. To increase the likelihood of detection, some individuals are assessed with an EEG for 24 to 48 hours.

Interestingly, vitamin B6 with magnesium as well as dimethylglycine (DMG) are known to reduce or eliminate seizure activity in some individuals, even in cases where seizure drugs are ineffective.

Note that the majority of autistic individuals do not have seizures during puberty. In fact, many parents have told me that their son/daughter actually experienced a dramatic developmental leap forward during this period.

Parents of autistic children should be aware of the possible positive and negative changes that can occur with puberty. Of particular importance is the need for parents to be cognizant of the fact that about 25% of autistic individuals may experience clinical or subclinical seizures which, if left untreated, can lead to deleterious effects.

The Autism Research Institute distributes an information packet on seizures/epilepsy.
Click here to learn how to obtain this packet.