NUR 334 PHARMACOLOGY EXAM 1 MOD 1 – 2 COMPREHENSIVE QUESTIONS
AND VERIFIED ANSWERS ( DETAILED & ELABORATED)
There are some serious conditions, how-ever, that may require pharmacotherapy in
patients who are pregnant or lactating. For examples are
if the patient has epilepsy, hypertension, or a psychiatric disorder prior to the pregnancy,
infections, UTI, STI
In general, drugs that are water soluble, ionized, or bound to plasma proteins are ------------
--likely to cross the placenta.
LESS or MORE
LESS
The fetal membranes contain ----------------- that detoxify certain substances as they attempt
to cross the membrane.
enzymes
During Pregnancy: ABSORPTION
Hormonal changes as well as the pressure of the expanding uterus on the blood supply to
abdomi-nal organs
Increased levels of progesterone can delay gastric emptying,
Gastric acidity is also decreased,
Progesterone causes changes in the respiratory system during pregnancy—increased tidal
volume and pulmonary vasodilation—that may cause inhaled drugs to be absorbed to a greater
extent.
During Pregnancy: DISTRIBUTION & METABOLISM
The increased blood volume in the mother causes dilution of drugs and decreases plasma
protein concentrations, affecting drug distribution
Blood flow to the uterus, kidneys, and skin is increased whereas flow to the skel-etal muscles is
diminished.
Fat-soluble drugs are distributed into the lipid-rich breast milk and may be passed to the
lactating infant.
During Pregnancy:: EXCRETION
By the third trimester of pregnancy, blood flow through the mother's kidneys increases by over
50%. This increase has a direct effect on renal plasma flow, glomerular filtration rate, and renal
tubular absorption. Thus, drug excretion rates may be increased, and doses of many medications
may need to be adjusted
, 2
A teratogen
is a substance, organism, or physical agent to which an embryo or fetus is exposed that produces
a per-manent abnormality in structure or function, causes growth retardation, or results in death.
Potential fetal consequences include
intrauterine fetal death, physical malformations, growth impairment, behav-ioral abnormalities,
and neonatal toxicity.
Preimplantation period.
Weeks 1 to 2 of the first trimes-ter are known as the preimplantation period. Before implantation,
the developing embryo has not yet estab-lished a physical connection to the mother. This is
some-times called the "all-or-none" period because exposure to a teratogen either causes death of
the embryo or has no effect.
Drugs such as nicotine, however, can create a negative environ-ment for the embryo and
potentially cause intrauterine growth retardation.
Embryonic period.
During the embryonic period, from 3 to 8 weeks postconception, there is rapid development of
internal structures. This is the period of maximum sensitivity to teratogens.
Fetal period.
The fetal period is from 9 to 40 weeks post-conception or until birth. During this time, there is
continued growth and maturation of the fetus's organ systems. Blood flow to the placenta
increases and pla-cental vascular membranes become thinner. Such alter-ations maximize the
transfer of substances from the maternal circulation to the fetal blood.
Most drugs are category C because
very high doses in laboratory animals often produce teratogenic effects.
All category D and X drugs should be avoided during pregnancy due
to their potential for causing serious birth defects.
Current FDA pregnancy category: Risk category A
Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal
abnormalities in any trimester of pregnancy
Examples
Prenatal multivitamins, insulin, levothyroxine, folic acid
AND VERIFIED ANSWERS ( DETAILED & ELABORATED)
There are some serious conditions, how-ever, that may require pharmacotherapy in
patients who are pregnant or lactating. For examples are
if the patient has epilepsy, hypertension, or a psychiatric disorder prior to the pregnancy,
infections, UTI, STI
In general, drugs that are water soluble, ionized, or bound to plasma proteins are ------------
--likely to cross the placenta.
LESS or MORE
LESS
The fetal membranes contain ----------------- that detoxify certain substances as they attempt
to cross the membrane.
enzymes
During Pregnancy: ABSORPTION
Hormonal changes as well as the pressure of the expanding uterus on the blood supply to
abdomi-nal organs
Increased levels of progesterone can delay gastric emptying,
Gastric acidity is also decreased,
Progesterone causes changes in the respiratory system during pregnancy—increased tidal
volume and pulmonary vasodilation—that may cause inhaled drugs to be absorbed to a greater
extent.
During Pregnancy: DISTRIBUTION & METABOLISM
The increased blood volume in the mother causes dilution of drugs and decreases plasma
protein concentrations, affecting drug distribution
Blood flow to the uterus, kidneys, and skin is increased whereas flow to the skel-etal muscles is
diminished.
Fat-soluble drugs are distributed into the lipid-rich breast milk and may be passed to the
lactating infant.
During Pregnancy:: EXCRETION
By the third trimester of pregnancy, blood flow through the mother's kidneys increases by over
50%. This increase has a direct effect on renal plasma flow, glomerular filtration rate, and renal
tubular absorption. Thus, drug excretion rates may be increased, and doses of many medications
may need to be adjusted
, 2
A teratogen
is a substance, organism, or physical agent to which an embryo or fetus is exposed that produces
a per-manent abnormality in structure or function, causes growth retardation, or results in death.
Potential fetal consequences include
intrauterine fetal death, physical malformations, growth impairment, behav-ioral abnormalities,
and neonatal toxicity.
Preimplantation period.
Weeks 1 to 2 of the first trimes-ter are known as the preimplantation period. Before implantation,
the developing embryo has not yet estab-lished a physical connection to the mother. This is
some-times called the "all-or-none" period because exposure to a teratogen either causes death of
the embryo or has no effect.
Drugs such as nicotine, however, can create a negative environ-ment for the embryo and
potentially cause intrauterine growth retardation.
Embryonic period.
During the embryonic period, from 3 to 8 weeks postconception, there is rapid development of
internal structures. This is the period of maximum sensitivity to teratogens.
Fetal period.
The fetal period is from 9 to 40 weeks post-conception or until birth. During this time, there is
continued growth and maturation of the fetus's organ systems. Blood flow to the placenta
increases and pla-cental vascular membranes become thinner. Such alter-ations maximize the
transfer of substances from the maternal circulation to the fetal blood.
Most drugs are category C because
very high doses in laboratory animals often produce teratogenic effects.
All category D and X drugs should be avoided during pregnancy due
to their potential for causing serious birth defects.
Current FDA pregnancy category: Risk category A
Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal
abnormalities in any trimester of pregnancy
Examples
Prenatal multivitamins, insulin, levothyroxine, folic acid
