pharmacology Flashcards
You discover a new drug that a college of yours from asia minor shared with you that he says is all the rage where she’s from. It’s a pregnancy drug that is lipophilic and has a high pka. Unfortunately you don’t know much more about it. Do you think is safe? explain
No lipophillic drugs can cross the placenta easily and molecules with high pka’s have the potential to become ionized and then trapped in the fetus leading to a dangerous accumulation of drug.
Protein binding in the fetus can be different than in the pregnant mother, why does this matter? Which placental transporters help decrease fetal drug concentrations?
Protein binding by the fetus is analogous to ion trapping. Lower lipid soluble drugs are most affected and can be bound preventing excretion.
Placental transporteres P-gp (glycoprotein) , and BCRP help decrease fetal concentration of drugs.
What new components have been added to pregnancy categories for drugs? What 3 new categories are there?
Pregnancy, lactation, and reproductive potential in m/f
Pregnancy exposure registry (monitors outcomes of women exposed to certain drugs)
Risk summary of all data (human and animal)
Prescribing risk benefit counseling
Data backing up reasoning
Lactation
Drug effects on breastfed child and on milk production
Clinical counseling
Data
Reproductive potential both sexes
You’re re-evaluating you patients blood pressure medication as they have chronic HTN, and during the visit your nurse informs you that your patient is pregnant. How might this effect her prescription of lisinopril? Explain the drugs MOA
Lisinopril and ACE inhibitors in general cause significant renal failure in infants.
MOA inhibits peptidyl dipeptidase (ACE), which converts Angiotensin I to Angiotensin II (vasoconstrictor)
You have a baby in the NICU you notice trembling crying (high pitched), who then vomits and continues crying. What drug abuse of the mother would be consistent with this?
NAS neonatal abstinence syndrome- drug withdrawal from opioids.
Which drug decreases hospital stay, and NAS as compared to methadone?
Buprenorphine
What are some of the general effects on the fetus to Rx teratogens?
Direct effect on maternal tissue
Interference with placental exchange of O2 and nutrients
Direct effects on the differentiation of tissue in the fetus
Deficiency of critical substances
What syndrome in a fetus is caused by anti seizure drugs?
fetal hydantoin syndrome
phenytoin, phenobarbital, carbamazepine
What are some of the characteristic features of FAS?
low nasal bridge, epicentral folds, thin upper lip, poor growth, uncoordinated, delayed development-thinking, speech, social skills. Heart defects.
Increased risk of miscarriage ETOH
You’re doing an US of a fetus with growth restriction and notice your patients hx is positive for a previous spontaneous abortion. Unfortunately she also had a child die from SIDS. What substance is she exposed to that makes you concered about the present childs health?
Tobacco smoking/nicotine
You have a patient admitted with signs and symptoms of preterm labor how should you handle risk of GBS? She turns out to be having some brackston hicks contractions instead what should you do? What focused drug hx do you need before any drug administration can be done? How would you handle a patient with a severe allergy to the first line therapy that is in a hospital setting with resistant GBS?
Obtain a vaginal-rectal swab for GBS culture and start GBS prophylaxis treatment. If not in true labor discontinue treatment.
Drug hx- penicillin allergy
IF severe penicillin allergy you can’t give cephalosporines and if the strain is resistant (to clindamycin and erythromycin; or no data available) then use vancomycin.
Mifepristone has what MOA? What drug is it taken in conjunction with? How do they work synergistically together?
Progesterone receptor antagonist which causes decay of the decidua and detachment of the conceptus from the uterine wall. Its used in conjunction with misoprostol which stimulates uterine contractions, made easier by mifepristones sensitization of PG in the uterus.
Misoprostol has what 5 drug roles? What PG is it an analog to?
Abortifacient
Ripen/soften the cervix prior to labor
Induce labor
Treat postpartum hemorrhage via contraction of uterus
AND… Treat peptic ulcers by inhibiting gastric acid secretion from parietal cells and thus promoting gastric mucosa and bicarb secretion, as an analog to PGE1, not surprising side effect include cramping.
Which prostaglandins stimulate uterine contractions?
PG E1,2, F2alpha
Name the PG stimulated by the abortifacients carboprost and dinoprostone and the specific uses of these drugs.
Carboprost PGF2alpha used to treat postpartum hemorrhage due to uterine atony
Dinoprostone PGE2 (vaginal suppository) used to evacuate the uterine contents in case of failed abortion or intrauterine fetal death
