Drugs in pregnancy Flashcards
effect on creatinine clearance
increases
effect on protein binding
most increase protein binding
hihgly protein bound drugs effected
effect on gastric emptying
decreased therefore increased absorption
effect on plasma volume
increases by 50%
can get anemia if RBC mass lags behind
effect on skin absorption
increased becuase increased vascularity
effect on cardiac output
increases 2 fold
if heart cant pull it off get edema in the legs
effect on peripheral resistance
decreases
effect on diastolic BP
decreases
effect on pulmonary resistance
increases
effect on colloid oncotic pressure
decreases
change in blood gas
increase ppH
decrease CO2
placentas major functions
transfer nutrient and oxygen remove waste products synthesize hormones, peptides, steroids link between the circulations barrier to protect from drugs/toxin in the maternal blood
what happens to blood flow through the placenta to maternal side during pregnancy
increases
why is metabolism different in the fetus
liver enzymes are different
kidney is immature, filtration reduced
what are some adverse drug reactions that occur
teratogenesis osteoporosis uterin stimulation or suppression deug dependent infant breathing difficulties in neonat impaired intellectula or social development
what is the risk of malformations with most teratogens
10%
Why is it hard to prove a drug is teratogenic
incidence of congenital anomalies is low
animal tests not applicable
exposure needs to be prolonged
controlled experiment cant be done in humans
behavioural issues hard to identiy or link
requirements to prove a drug is a teratogen
must cause specific set of malformations
act only between 4-7 weeks of gestation
incidence should increase with increasing dose and duration of exposure
if there is no proof for teratogenicity is the drug safe
no
shepards principles of teratolofy
agent must be rpesent during critical periods of developmetn
acts directly on the embryo
experimental models corroborating the findings
preimplantation/presomite period
conception to 2 weeks
somite period
2-4 weeks
organ structure formation period
4-8 weeks
organ function/substructure period
8+ weeks
what occurs if teratogen exposed during first trimester embryonic period (3-8wks)
gross (structural) abnormalities
what occurs if teratogen exposed during the fetal period (9-40wks)
functional problems
learning deficits
behavioural abnormalities
what are two commone types of teratogenic drugs
antieliptics
antipsychotics
live vaccines
nsaids
problems from diethylstilbesterol
vaginal cancer
female children born with vaginal and cervical carcinomas and uterine anomalies
male children abnormal genitalia/sperm
thalidomide malformations
absence of limbs (phocomlia) gongenital heart defects eye defect urogenital GI hearing loss
SSRIs in pregnancy
disocntinuing high risk because stress bad
treated with low doses appears safe
maybe cardiac malformations
what do women think is the teratogenic risk
25%
