Medication use in Pregnancy & Lactation

Question 1

CURRENT FDA labeling requirements:

Answer 1

1. Pregnancy (includes labor and delivery)
2. Lactation (includes nursing mothers)
3. Females and males of reproductive potential

Question 2

______% of medicines approved since 1980 have enough information to determine their safety during pregnancy

Answer 2

Fewer than 10

Question 3

The FDA estimates that ____ % of all birth defects are caused by medications

Answer 3

<1

Question 4

When prescribing medications to pregnant people here are some things to consider:

Answer 4

○ Minimize the number taken
○ Limit use to situations with significant benefit
○ Choose the med with the best safety profile
○ Use at the lowest dose and for the shortest duration possible

Question 5

Regarding medication use, Avoid fetal drug exposure, when possible, especially in the _____

Answer 5

first trimester

Question 6

Placenta general functions

Answer 6

1. Gas exchange (wholly responsible for O2 and CO2 transfer)
2. Metabolic transfer
3. Endocrine function
4. Immunological functioning

Question 7

Medication use in pregnancy is considered when the drugs _____

Answer 7

benefits outweigh known risks

Question 8

Drugs that Do Not Cross the Placenta do not:

Answer 8

● Do not have direct toxic effect
● Do not have teratogenic effect

Question 9

T/F Drugs that Do Not Cross the Placenta will not harm the fetus

Answer 9

F

Question 10

How can Drugs that Do Not Cross the Placenta harm the fetus?

Answer 10

1. Constricting Placental Vessels
   a. Impairs gas and nutrient exchange
2. Producing Severe Uterine Hypertonia (uterine contractions)
   a. Results in anoxic injury
3. Altering Maternal Physiology
   a. I.e. hypotension

Question 11

A drugs penetration of the placenta depends on:

Answer 11

● Drug’s Molecular Weight
● Extent of its binding to another substance
○ I.e. - carrier protein
● Area available for exchange across
placental villi
● Amount of drug metabolized by the
placenta

Question 12

Molecular Weight importance in drugs that do/dont cross the placenta

Answer 12

● Drugs with molecular weight <500 daltons
○ Readily cross the placenta (into fetal circulation)
● Drugs with high molecular weight (I.e. protein-bound drugs)
○ Usually do not cross the placenta

Question 13

Drug effects on developing fetus at < 20 days post-fertilization

Answer 13

■ “All or nothing effect”
● Kills the embryo or has no effect
● Teratogenesis unlikely

Question 14

Drug effects on developing fetus at 20-56 days post-fertilization

Answer 14

Teratogenesis=most likely to occur!
● Spontaneous abortion
● Sublethal gross anatomic defect (teratogenesis)
● Covert embryopathy (manifests later in life)
● No measurable effect

Question 15

Drug effects on developing fetus in the 2nd/3rd trimesters

Answer 15

■ Teratogenesis unlikely
■ Altered growth and function of normally formed organs

Question 16

Treatment of vaginal candidiasis during pregnancy

Answer 16

● TOC - Topical Clotrimazole or
miconazole X 7 days vaginally
● Avoid oral azole particularly in the first
trimester
○ May increase risk of miscarriage and
its impact on birth defects is unclear

Question 17

Thalidomide effects on pregnancy

Answer 17

Prescribed for nausea and morning sickness in pregnancy
● 100,000 infants worldwide born with Phocomelia (malformation of limbs) only 40% survived

Question 18

Which drug caused Phocomelia
(malformaiton of limbs)?

Answer 18

Thalidomide

Question 19

Bacterial vaginosis treatment during pregnancy & risks

Answer 19

● TOC: Oral or topical metronidazole
○ Some providers avoid metronidazole in first trimester (b/c crosses placenta), but
meta-analysis has not found any relationship to birth defects. It is mutagenic in bacteria and carcinogenic in mice but there is no human evidence of harm

Question 20

Pregnant pts + common cold = _____

Answer 20

↑↑ risk of rhinosinusitis and
eustachian tube dysfunction

Question 21

Acute Sinusitis treatment in pregnancy (bacterial) & what to avoid

Answer 21

○ If using an antibiotic follow traditional sinusitis treatment plans. PCN and cephalosporins are the safest classes
● Beclomethasone (Beconase AQ) or Budesonide (Rhinocort) nasal sprays
● Oxymetazoline (Afrin) nasal spray (max. 3 days)
● Rhinorrhea
○ Ipratropium bromide nasal spray (Atrovent) or cromolyn nasal sprays (Nasalcrom

○ Avoid:
■ Doxycycline (teeth staining)
■ Levofloxacin (cartilage abnormalities)

Question 22

Strep Pharyngitis treatment in pregnancy & risks

Answer 22

● TOC: Penicillin, amoxicillin or cephalosporins
no risks mentioned

Question 23

Oral decongestants use in pregnancy

Answer 23

avoid during first trimester
○ TOC for seasonal allergies in 2nd -3rd trimester -
Pseudoephedrine 60 mg max 4x/day

Question 24

beta-blocker that is not contraindicated with pregnancy

Answer 24

labetalol

Question 25

ACE/ARBS safety in pregnancy

Answer 25

● ACE Inhibitors and ARBs are Contraindicated
○ Because of potential for teratogenesis
■ Growth retardation, renal failure, persistent PDA, fetal
hypotensive syndrome

Question 26

Treatment options for acne in pregnancy

Answer 26

○ Oral or topical erythromycin
○ Topical clindamycin
○ Topical azelaic acid
○ Benzoyl Peroxide - limited use; (less recommended, USE caution or if other
treatment options fail)

● Many treatments for acne are contraindicated in pregnancy (XXXXX)

Question 27

Migraine treatment in pregnancy

Answer 27

MUST r/o preeclampsia in every >20 wks gestation pt
● Migraine
○ TOC: Acetaminophen
○ 2nd line: acetaminophen combo treatments
■ I. e. - acetaminophen/metoclopramide; acetaminophen/codeine;
acetaminophen/caffeine/butalbital
○ 3rd line: NSAID

Question 28

Safe Hypertension treatments during pregnancy

Answer 28

● First choice: Labetalol (beta-blocker) - (Bronchospasm SE)
● Nifedipine (long acting CCB)
● Oral Hydralazine (direct vasodilator)
○ Only as “add-on” therapy d/t reflex tachycardia
● ACE Inhibitors and ARBs are Contraindicated

Question 29

Vertigo treatment with pregnancy

Answer 29

● TOC: Meclizine (for non-pregnant pts, it’s antihistamines)

Question 30

Depression treatment in pregnancy

Answer 30

● Initial: CBT
● Rx TOC - SSRI’s predominantly - sertraline (can also use during lactation)
- Avoid paroxetine and Fluoxetine
● If resistant to SSRI, switch to a different SSRI and/or change their current dose of the SSRI. if still refractory switch to an SNRI (typically venlafaxine)
● MAOI’s contraindicated

Question 31

Anxiety treatment in pregnancy

Answer 31

● Usually antidepressants are the optimal choice
● However, if anxiety is severe:
○ Combo antidepressant with Benzo (for a short bridge duration < 2 weeks)
■ Clonazepam
■ Lorazepam

Question 32

Nausea & Vomiting prevention in pregnancy:

Answer 32

● Prevention: folic acid
● Basics: Hard candy, small meals, ginger, take ½ prenatal vitamin or take vit w/o iron
● Avoid environmental triggers
● Acupuncture and acupressure (no evidence - but has placebo effect for some)

Question 33

Nausea treatment in pregnancy

Answer 33

○ Pyridoxine (Vit B6) monotherapy
○ TOC (if monotherapy fails): Pyridoxine (Vit B6)-doxylamine succinate combo
therapy (Diclegis/Bonjesta)

Question 34

Treatment for Nausea if vomiting persists

Answer 34

○ Diphenhydramine 25-50 mg Q4-6h
○ Meclizine 25 mg Q6h
○ Consider adding a dopamine antagonist (Prochlorperazine (Compazine),
promethazine, or metoclopramide (Reglan))

Question 35

Vomiting + hypovolemia treatment in pregnancy

Answer 35

○ Fluid replacement
○ IV antiemetic therapy in ED (often Ondansetron/Zofran)
○ Add Thiamine supplement to IV fluids (prevent Wernicke’s encephalopathy)
○ Home on Ondansetron (Zofran) = > 10 wks, use CAUTION if prior to 10 wks

Question 36

Zofran safety in pregnancy

Answer 36

use CAUTION if prior to 10 wks

Question 37

Headache and Pain treatment in pregnancy and lactation

Answer 37

● Acetaminophen: safe in all 3 trimesters and lactation
Maximum recommended dose: 3000 mg/day
● Aspirin: Avoid unless prescribed
● NSAIDS: 1st Tri = miscarriage; 3rd Tri premature PDA closure, renal
toxicity. Avoid in pregnancy
Lactation: Ibuprofen preferred
Post-Partum: Naproxen frequently used

Question 38

Antibiotics without KNOWN teratogenic effects

Answer 38

● Penicillins
● Cephalosporins
● Specific macrolides
○ Erythromycin
○ Azithromycin = usually best option
○ Clindamycin
● Augmentin
● Metronidazole
○ Avoid 1st trimester

Question 39

Antibiotics contraindicated in treatment

Answer 39

○ Aminoglycosides (Gentamicin etc…)
■ Ototoxicity and nephrotoxicity
○ Chloramphenicol
■ gray baby syndrome
○ Fluoroquinolones (levofloxacin, cipro etc…)
■ Fetal cartilage damage
○ Tetracyclines (doxycycline)
■ Maternal hepatotoxicity
■ Inhibition of fetal bone and fetal
discolored teeth

Question 40

Specific caution with bactrim in pregnancy

Answer 40

Bactrim (trimethoprim-sulfamethoxazole)
■ Avoid in 1st tri - interferes with folate synthesis

Question 41

Specific caution with Nitrofurantoin in pregnancy

Answer 41

■ Avoid in 3rd tri (if possible) - May lead to kernicterus
(bilirubin induced brain dysfunction)

Question 42

Specific caution with macrolides in pregnancy

Answer 42

■ Erythromycin
■ Clarithromycin
1. Don’t use unless there are no alternatives

Question 43

Specific caution with metronidazole in pregnancy

Answer 43

Avoid use in 1st trimeste

Question 44

Which antibiotic can cause gray baby syndrome?

Answer 44

Chloramphenicol

Question 45

Tetracyclines (doxycycline) safety in pregnancy

Answer 45

Contraindicated
Maternal hepatotoxicity
■ Inhibition of fetal bone and fetal
discolored teeth

Question 46

Which antibiotic can cause Ototoxicity and nephrotoxicity in pregnancy?

Answer 46

Aminoglycosides (Gentamicin etc…)