week 4: Ch. 8-10 [Lifespan pharm] Flashcards
Most medications can cross the ____________ and are secreted in breast milk
placenta
_____% of women take at least one medication during pregnancy
90%
[and 80% during first trimester]
Pharmacotherapy is _____________ if possible until after delivery & lactation
postponed
What kind of conditions must be managed during pregnancy?
preexisting conditions
pregnancy complications
conditions unrelated to pregnancy
Physiological changes during pregnancy can alter the normal pharmacokinetic response by:
speeding it or slowing it
increased levels of _______________ cause a decrease in gastric tone and intestinal motility, resulting in delayed gastric emptying > extended drug absorption time
progesterone
High __________ levels cause increased hydrochloric
acid production.
▪ May affect absorption of certain acid labile drugs
estrogen
______________ increases pulmonary blood flow,
respiratory tidal volume, and minute volume by 40%
Progesterone
▪ Respiratory agents may be absorbed in larger
quantities.
▪ Higher serum drug levels
Distribution is affected during pregnancy by changes in total body water, which may increase by:
over 50%
[ Leads to greater hemodilution of plasma proteins and drugs ]
Highly lipophilic drugs are distributed into lipid-rich _____________
breast milk.
Maternal heart rate may increase up to ____ beats a minute leading to greater drug distribution.
15
Metabolism is significantly altered by __________
– Some cytochrome enzymes increase & others are decrease
pregnancy
Excretion is _____________ during pregnancy
▪ Renal changes due to pregnancy results in
increased renal elimination of drugs
▪ Doses of medications must be adjusted
Enhanced
Placenta = Temporary organ
– Allows for ___________ and ________ exchange between mother and fetus
nutrition and gas
____ % of the mother’s cardiac output circulates
through placenta
▪ Maternal blood does not circulate through fetus
10%
The __________ offers degree of protective filtration of maternal blood
▪ Prevents certain harmful substances from reaching fetus
▪ Vitamins, fatty acids, glucose, and electrolytes freely pass from mother to fetus.
placenta
Most drugs cross placenta by :
simple diffusion.
Few drugs cross placenta by way of :
active transport.
Drugs do not have to cross the placenta or enter fetal blood to cause:
fetal abnormalities.
Drugs may cause constriction of placental blood vessels, impairing :
nutrient exchange
Factors impacting transfer of drugs across placenta
–____________ level in the mother
▪ The higher the dose taken by mother, the more
drug circulates through the placenta.
▪ Rationale for prescribing lowest effective dose
– _________ of the drug
▪ Highly lipid-soluble drugs cross placenta more
easily than water-soluble drugs
*Molecular __________
*Protein binding
*Drug ionization
*_________________ to the placenta
– Plasma drug level in the mother
▪ The higher the dose taken by mother, the more
drug circulates through the placenta.
▪ Rationale for prescribing lowest effective dose
– Solubility of the drug
▪ Highly lipid-soluble drugs cross placenta more
easily than water-soluble drugs
*Molecular size
*Protein binding
*Drug ionization
*Blood flow to the placenta
Teratogens
– Substance, organism, or physical agent that
interferes with growth or development of embryo or fetus and produces permanent abnormality or death.
– Potential fetal consequences
▪ Intrauterine fetal death
▪ Physical malformations
▪ Growth impairment
▪ Behavioral abnormalities
▪ Neonatal toxicity
Incidents of teratogenic events occur in approximately ____% of all pregnancies
3%
Well-known example of a __________ is thalidomide.
teratogen
thalidomide effects
– Causes fetal effects from 35 to 48 days after last menstrual period
▪ 35 to 37 days, no ears
▪ 39 to 41 days, no arms
▪ 41 to 43 days, no uterus
▪ 45 to 47 days, no tibia
▪ 47 to 49 days, triphalangeal thumbs