Explain the factors which influence the transfer of drugs across the placenta to the foetus.
Good answers showed an understanding of diffusion, the influence on transfer of lipid
solubility, molecular size, degree of ionisation and protein binding. They also made reference
to placental transporters and placental metabolism. Extra points were scored for mentioning
that the real concern is teratogenicity to the foetus.
Syllabus O2 2d
Reference: Katzung 10th edition p 971-973.