At 6 months Beth had absent/staring seizures and was put onto phenobarbitol elixir. Initially a loading dose was given intravenously to build up the amount in her bloodstream, this dose was 100mg.  Beth had a side effect of "paradoxical excitement" as the phamplet states, or put more simply, she was as high as a kite from this.  She would react with smiles and laughter to the simplest stimuli for about 24 hours.  Ongoing she was placed on a dosage of 15mg twice daily.  Since that time we have noticed moodiness and increased drowsiness - we have not seen her smile or laugh since she went on it.  We changed over to a tablet form and crushed it and mixed it with food for her which was much better to take than the sticky elixir.

Phenobarbitol does have a clear side effect of drowsiness and for this reason its not generally given to older children, only infants, as it can impact with attentiveness and learning ability.

Apparently there is an interaction with phenobarbitol and paracetamol, and as such giving paracetamol based pain killers may not be as effective and given in high doses over long periods may lead to liver issues.

Both prednisone and phenobarbitol are "addictive" and need to be weaned off rather than stopped immediately.