Drug Therapy During Pregnancy and Breastfeeding Flashcards
By the third trimester, renal blood flow is _______, causing a large increase in the glomerular filtration rate
doubled
To compensate for accelerated excretion, dosage must be increased
Hepatic metabolism ______ during pregnancy
increases
Tone and motility of bowel______ in pregnancy, causing intestinal transit time to ____________
decrease
increase
Due to prolonged transit time, there is more time for drugs to be absorbed. This could _______ levels of drugs whose absorption is usually poor. A reduction in dosage might be needed.
increase
Drugs that are ___________ cross the placenta easily
lipid soluble
Drugs that are ______, __________, or ________ cross the placenta with difficulty
ionized, highly polar, or protein bound
The provider should….
assume that any drug taken during pregnancy will reach the fetus
Pregnant patients who take heparin are at risk of
osteoporosis which can cause compression fractures of the spine
Withdrawal syndrome will ensue if…
regular use of dependence producing drugs (heroin, barbiturates, alcohol) during pregnancy and the drug dependent infant is not supported with the drugs
Drug effect of greatest concern that produces congenital anomalies
teratogenesis
Causes of congenital anomalies
genetic predisposition, environmental chemicals, and drugs
____________are produced by exposure to teratogens during embryonic period
gross malformations
Teratogen exposure during fetal period usually disrupts _____ rather than gross anatomy.
function
In the fetal period, growth and development of the brain are especially important. Disruptions of brain development can result in___________
learning deficits and behavior abnormalities
Preimplantation/presomite period, teratogens act in an
all or nothing fashion
To prove a drug is a teratogen, 3 criteria must be met:
- cause a characteristic set of malformations
- act only during a specific window of vulnerability
- incidence of malformations should increase with increasing dosage and duration of exposure
Fast acting teratogen, a single dose exposure
thalidomide
Must be taken repeatedly in high doses for gross malformation to result
alcohol
Teratogens that affect ____ may be nearly impossible to identify
behavior
Teratogens that produce delayed effects are hardest to identify
diethylstilbestrol
____________ taken late in pregnancy may cause hypoglycemia and respiratory complications along with a hypotonic state that is commonly called floppy infant syndrome
benzodiazepines
causes congenital deafness
aminoglycoside streptomycin
fetal hemorrhage is associated with
warfarin
spontaneous abortion can be caused by
misoprostol
How do you minimize drug risk during pregnancy?
develop a comprehensive list of current drugs used including prescriptions, OTC, nutritional supplements, and recreation drugs
Vitamin___ can cause craniofacial anomalies and CNS, cardiac, and thymus abnormalities
A
Some diseases like _____ pose a greater risk to fetal health than the drugs used for treatment
epilepsy, asthma, diabetes
When a pregnant patient has been exposed to a known teratogen, the first step is to
determine exactly when the drug was taken and exactly when the pregnancy began
If drug exposure was NOT during the period of organogenesis, the patient should be reassured that the risk of drug-induced malformation is
minimal
What should be done if the exposure did occur during organogenesis?
- references should be consulted to determine the type of malformation
- at least 2 ultrasound scans should be tone to assess the extent of injury
- if sever, termination of pregnancy should be considered
Drugs that are _______ enter breast milk readily
lipid soluble
Drugs that are ____, ____, or ____ tend to be excluded from breast milk
ionized, highly polar, or protein bound
Drug classes that are contraindicated during breastfeeding
controlled substances, anticancer, immunosuppressants, others
______________are associated with irritability or sedation and may decrease milk supply
first generation antihistamines
Most drugs detected in milk are in concentrations that
are too low to cause harm
When drugs must be used, steps taken to minimize risk
- dosing immediately after breastfeeding
- avid drugs with long half-life
- avoid sustained release formulations
- choose drugs that tend to be excluded from milk
- choose drugs that are least likely to affect the infant
- avoid drugs that are known to be hazardous
- use the lowest effected dosage for the shortest time possible
- abandon plans to breastfeed if necessary
Teratogenic effects during weeks 4-5 of gestation
Amelia/meromelia
Teratogenic effects during weeks 3-6 of gestation
TA, ASD, VSD, neural tube defects
Teratogenic effects during weeks 5-6 of gestation
cleft lip
Teratogenic effects during weeks 4-9 of gestation
low-set malformed ears, deafness, microphthalmia, cataracts, glaucoma
Teratogenic effects during weeks 6-16 of gestation
intellectual disorders
Teratogenic effects during weeks 6-8 of gestation
heart, upper and lower limbs, cleft palate
Teratogenic effects during weeks 16-38 of gestation
less sensitive: CNS, ears, eyes, teeth, palate, external genitalia
