Effect of over-the-counter drugs on the unborn child: what is known and how should this influence prescribing?

The developing organism is unique in its responsiveness to drugs. The predictability of therapeutic effectiveness and safety of drugs in pregnancy using the adult as a model for pharmacokinetics and pharmacodynamics can result in grave consequences in the fetus. There exists a general misconception that since over-the-counter (OTC) drugs are readily available, these pharmaceutical agents can be viewed as safe to use by adults. Ingestion of OTC preparations during pregnancy results in placental transfer and accumulation of these drugs in the fetus. As the fetus lacks the ability to handle pharmaceutical agents, since renal function, metabolic pathways, etc. are not fully developed, drug exposure in utero may produce deleterious effects in the fetus but not the mother. Clinicians are aware of drug-induced effects on the fetus and have dramatically reduced the use of prescription drugs during pregnancy. However, the use of self-medication (OTC) has significantly increased during pregnancy through extensive, effective advertising by the pharmaceutical industry and lack of sufficient data indicating an OTC effect on the fetus. However, the consequences of OTC drug use need to be established, since these compounds continue to be used extensively, especially during pregnancy.