Ethical dilemmas of potential adverse events

Doctors should advise patients of recognised adverse events of proposed therapy. It remains unclear what responsibility attaches to suspected potential for adverse events if these have not been reported. Vigabatrin (VGB) is a gabaergic anti-epileptic medication (AEM) reported to produce tunnel vision with constricted fields. Tiagabine (TGB), also a gabaergic AEM recently approved for sale, has not been reported to cause field defects but raising GABA also raises concern. Doctors must decide what needs to be discussed with patients; should patients on TGB have field testing similar to those on VGB; what should be done if constricted fields are confirmed in asymptomatic patients; and what reporting procedures should be adopted.