Phenobarbital is a phenobarbiturate used as an anticonvulsant, sedative, or hypnotic, depending to the doses prescribed. It has been on the French market since 1950. As with other antiepileptic drugs, the risk of giving birth to an infant with facial grooves and cardiopathies is increased, although it is not yet possible to ascribe this risk to drugs rather than to seizures. The combined use of phenobarbital and other antiepileptics (particularly diphenylhydantoin) increases its teratogenic effect. Some French authors have described facial dysmorphism that is characteristic of children born to mothers being treated with barbiturates. It is very similar to that of fetal hydantoin syndrome, with small saddle nose, large mouth with no philtrum, synophrys, and deformed helix. These signs disappear considerably with growth. Risk is much lower than with other antiepileptic treatments for women having been treated with barbiturates only. A few series suggest mildly altered intellectual capacities in children having been exposed in utero. Continued treatment during pregnancy also induces risk of hemorrhage in the newborn, and can be prevented by administering vitamin K. Large doses of barbiturates can cause addiction, and thus weaning signs such as tremulation and hyperactivity can be seen in the infant.
Last update: July 2005
- Dr Elisabeth ROBERT-GNANSIA