Mother and the Fetus
Many drugs cross the placenta, but only some of them can have an adverse
effect on the fetus because of the immature fetal metabolism and slower excre-
tion rates. Waste products are excreted into the amniotic fluid and then absorbed
by the mother or swallowed by the fetus.
Alcohol, barbiturates, and narcotics—such as diphenhydramine (Benadryl),
amobarbital (Amytal), diazepam (Valium), codeine, heroin, methadone, morphine,
propoxyphene (Darvon)—that are used during pregnancy can lead to harmful
effects on the newborn. Use of these drugs during pregnancy can create an
addiction in the newborn. The baby will go into withdrawal from the drug when
they are born. This can result in hyperactivity, crying, irritability, seizures and
even sudden death.
When taken by the mother during the first trimester, some drugs have a ter-
atogenic effect on the fetus resulting in fetal defects. This includes mutagenic
(genetic mutation) or carcinogenic (causing cancer) effects. These drugs include
Thalidomide, which causes abnormal limb development, and cocaine, which
causes miscarriages, fetal hypoxia (lack of oxygen), low-birth-weight infants,
tremors, strokes, increase in stillbirth rates, congenital heart disease, skull
defects, and other malformations.
Adverse side effects of the drug on the fetus can be avoided by carefully
checking the Pregnancy Category of the medication before the medication is
administered to a pregnant woman. Regardless of the Pregnancy Category
of the drug, always carefully observe the pregnant patient after administering
medication to assure that the patient doesn’t show any observable adverse
response.Pediatrics
Special care must be given when administering medication to pediatric patients
because their organs are immature and they might have difficulty absorbing,
distributing, and excreting the medication. This is especially true with neonatal
patients.Neonatal patients can receive some medication through breast milk.
However, because the mother has already metabolized and excreted the medica-
tion, less than the original dose is passed into breast milk.(^54) CHAPTER 3 Pharmacology and the Nursing Process