Pharm-Pregnancy Drugs-Melissa** Flashcards
What are the top ten drugs consumed during preggos? specifically: -#1? -#9? #10?
1 analgesics, #9 alcohol, #10 Fe + vitamins
Diethylstilbestrol (DES):
What was its former therapeutic use?
What was its teratogenic effect**?
Used to prevent premature birth
ONLY KNOWN TRANSPLACENTAL CARCINOGEN
-Causes VAGINAL clear cell adenocarcinoma in daughters born to mothers taking drug
Bendectin:
What was its former therapeutic use?
Why was it withdrawn from the market?
- # 1 anti-emetic used during preggos in 1950s-60s
- suspected teratogenicity (not confirmed)
Thalidomide:
What was its former/ current therapeutic use?
Why was it withdrawn from the market?
- Former anti-emetic
- Currently used chemotherapeutic agent
- Teratogenic effects: amelia (missing limb), phocomelia (misshapen limbs), facial/ear abnormalities
When is MOST damage by drugs done to fetuses?
During embryonic period: weeks 3-8 (patient may not know they are preggos)
List the fetal anomalies that can result during the following stages of intrauterine development:
Pre-organogenesis
Embryonic
Fetogenesis
Pre-organogenesis (wks1-2)–> all or nothing
Embryogenesis (wks3-8)–> CNS problems (spinabifida…), cardiac defects, etc.
Fetogenesis (wks9-38)–> gonadal, CNS, etc.
What percentage of birth defects are associated with drug exposure? What is the most common cause of birth defects? How does pregnancy influence drug absorption?
-4-5 percent of all birth defects due to drugs
-most defects have unkown cause
-note that pregnancy doesn’t change drug absorption
(the baby usually gets whatever you take!)
How does pregnancy influence drug distribution?
- ^ plasma volume + total body water = dilute drug
- DECREASE plasma albumin = ^ FREE FRACTION DRUG
How does pregnancy influence drug biotransformation?
^ opportunities to biotransform!
Mom liver + placenta + fetal liver
How does pregnancy influence drug excretion?
^ GFR up to 70% (renally excreted drugs will be lost at faster rate)
How do most drugs pass from mom to placenta?
How do amino acids and glucose cross?
What two types of drugs DO NOT cross the placenta?
- most: passive diffusion (larger go slower)
- AA’s and glucose cross via active transport
- Heparin + Insulin don’t cross, most others do
Define FDA Pregnancy Categories A, B, C, D, X:
–which is the target for therapy?
A = ZERO RISK (not many drugs fit here)
B = Goal; No risk in animal studies OR problems from animal studies not confirmed in human trials
C= No human studies available to trump problems from animal studies OR no studies available (still used)
D = PROBABLY NOT SAFE/ EVIDENCE OF HUMAN RISK; try not to use these
X = THESE ARE NOT ALLOWED IN PREGGOS; BENEFITS DO NOT OUTWEIGH RISK
Which category drugs are regularly used in preggos?
From where do we get most data confirming or denying safety of drug use in pregnancy?
A-C are commonly used with risk benefit analysis
*A don’t really exist, though.
Most data comes from data registries
Why should these drugs be avoided in early pregnancy?
- DES
- Warfarin
- Systemic retinoids
- Androgens in high doses
- Steroids in high dose
- Tetracyclines
- DES–> adenocarcinoma in daughters
- Warfarin–> MSK/CNS problems
- Systemic retinoids –> CNS, craniofacial, CV
- Androgens in high doses –> virilization etc.
- Steroids in high dose–>cleft palate
- Tetracyclines–>yellow teeth, decrease bone growth
Why are these drugs under high suspicion of producing abnormalities EARLY in preggos– what abnormalities are they thought to cause?
- Lithium
- Phenytoin
- Chloroquine
- Lithium –> Ebstein’s anomaly
- Phenytoin –> Everything bad
- Chloroquine–>deafness
List 5 antibiotic classses to be avoided in preggos and what they can do to the fetus:
- Co-trimoxazole–> folate antagonist + hyperbilirubinimia
- Chloramphenicol–> gray baby
- Aminoglycosides–> ototoxicity
- Sulfonamides–> Hyperbilirubinimia= kernicterus
- TCN: tooth discoloration, bone problems
ASN: what can it do and when in preggos is it dangerous?
Late preggos
- Kernicterus and fetal or maternal hemorrhage
Antithyroid Drugs: what can they do and when in preggos are they dangerous?
Late preggos
-Goiter and hypothyroid in baby
BDZs: what can they do and when in preggos are they dangerous?
Late preggos
- Floppy baby
Oral anticoagulants: what can they do and when in preggos are they dangerous?
Late preggos
- fetal/ retroplacental hemorrhage, microcephaly
(not IV heparin, heparin ok.)
Oral sulfonylurea hypoglycemics: what can they do and when in preggos are they dangerous?
Late preggos
- fetal hypoglycemia (intuitive, sulonfylureas = ^^ insulin)
What are the first and second line treatments for preggos with UTI?
#1 Nitrofurantoin, #2 Penicillins -Trimethoprim-Sulfamethoxazole (risk benefit!!)
How do we treat bacterial vaginosis in preggos?
TOPICAL Metronidazole
How do we treat vaginal candidiasis in preggos?
TOPICAL azoles
