Abstracts of articles relevant to this topic are available through PubMed, a service of the National Library of Medicine:

Herranz JL, Armijo JA, Arteaga R. Clinical side effects of phenobarbital, primidone, phenytoin, carbamazepine, and valproate during monotherapy in children. Epilepsia. 1988 Nov-Dec;29(6):794-804. PMID: 3142761.

In this study of almost 400 children, 64% of those who took phenobarbital had some kind of side effect but only 4% had to stop taking the medication. The children who took phenobarbital had more behavioral disorders than the other children, including excitement at low blood levels and depression at high levels.

Vining EP, Mellitis ED, Dorsen MM. Psychologic and behavioral effects of antiepileptic drugs in children: a double-blind comparison between phenobarbital and valproic acid. Pediatrics. 1987 Aug;80(2):165-74. PMID: 3112727.

In this study, 21 children with epilepsy each took phenobarbital and valproic acid (Depakote) during separate 6-month periods. The researchers found subtle but significant changes in intellectual function and behavior. While taking phenobarbital, the children did not seem to be sedated but they did significantly less well on tests of thinking than when they were taking Depakote. They also showed more hyperactivity and worse behavior.

Mattson, RH, Cramer, JA, et al. Comparison of carbamazepine, phenobarbital, phenytoin and primidone in partial and secondarily generalized tonic clonic seizures. New England Journal of Medicine313:145-151, 1985. PMID: 3925335.

Phenobarbital was as effective as the other medications for generalized tonic-clonic seizures in adults, but it was less likely than carbamazepine (Tegretol, Carbatrol) to completely control partial seizures. It had fewer intolerable side effects than primidone (Mysoline).

Mitchell WG, Chavez JM. Carbamazepine versus phenobarbital for partial onset seizures in children. Epilepsia. 1987 Jan-Feb;28(1):56-60. PMID: 3098555.

Some individuals taking each medication showed changes in behavior or cognition, but overall the groups of children taking one of these two medicines did not differ significantly.