Isotretinoin
Isotretinoin is a teratogen; there is about a 20–35% risk for congenital defects in infants exposed to the drug "in utero", and about 30–60% of children exposed to isotretinoin prenatally have been reported to show neurocognitive impairment. Because of this, there are strict controls on prescribing isotretinoin to women who may become pregnant and women who become pregnant while taking isotretinoin are strongly advised to terminate their pregnancies.
Glutaric aciduria type 1
5-hydroxytryptophan, the precursor of serotonin that is not metabolized to glutaryl-CoA, glutaric acid and secondary metabolites, could be used as an adjunct to selective tryptophan restriction, considering the risks associated with the procedure. However, the evidence in favour of selective tryptophan restriction remains insufficient and the consensus evolves towards the restriction of lysine only (Kolker & al. 2006).