Which of the following drug can be accumulated in foetus in very significant amount if given to pregnant mother?: (A) Thiopentone, (B) Propofol, (C) Midazolam, (D) Lignocaine
Answer is D. Local anaesthetic and opioids are bases. Once they reach the fetus they become nonionized (due to highly acidic pH) and can not come back to maternal circulation leading to toxic accumulations in fetus.