NAPLEX: Drug Use in Pregnancy & Lactation

What is considered the first trimester?

Week 0-12 (Pregnancy lasts 37-40 weeks usually?)

- Embryo most susceptible to birth defects caused by teratogens

What does a drug have to be able to do to be teratogenic?

It has to be able to cross the placenta into the fetal circulation

What organization publishes guidelines for safe and effective drug use in conditions impacting women?

The American College of Obstetricians and Gynecologists (ACOG)

How is a obstetric history described?

Gravida (G) and Para (P)

- Gravida is the number of times the person has been pregnant

- Para is the number of times a patient has given birth

What can folate (Vitamin B9) deficiency lead to?

Brain and spinal cord (neural tube defects)

- Adults should consume 400 mcg of dietary folate equivalents (DFE) per day

- During pregnancy, folate requirements increase to 600 mcg DFE/day.

- Females of childbearing potential should increase their folic acid consumption from dietary supplements, fortified food AND their regular diet

Vitamin D and Calcium in pregnancy

Pregnant women from 19-50 years old require 1,000 mg/day of calcium and 15 mcg/day (600 IU/day) of vitamin D

Old Pregnancy Categories

A: No Risk

B: No fetal risk via animal studies

C: Animal studies have shown harm to fetus but no studies in pregnant women. Only use if benefit outweighs the risk

D: Positive evidence of risk to the human fetus but the benefits may outweigh the risk

X: Use in pregnancy is C/I

Updated Pregnancy Sections in Package Inserts

8.1 Pregnancy

- a pregnancy risk summary is required for all medications that includes the risk of adverse developmental outcomes based on human and animal data and the drug's pharmacology

- includes any dose adj, maternal/fetal adverse reactions and disease risk

- includes pregnancy exposure registry info

- pregnant women should be encouraged to participate in registries which exist for select disease states and drugs

- the registries collect health info from women who take prescription drugs and vaccines when pregnat and breatfeeding

- info is collected on the newborn baby

8.2 Lactation

- includes whether the drug/metabolites are present in human milk, the effects on the breastfed infant and the effects on milk production

- if applicable, ways to minimize exposure and monitor for adverse reactions are included

8.3 Females and males of reproductive potential

- includes any effects on fertility and requirements for pregnancy testing and contraception

What immunizations are indicated for all pregnant women?

1. Inactivated influenza Vaccine

2. A single dose of Tdap during each pregnancy

What is a reputable, up-to-date resource for prescribing/dispensing to pregnant women?

Briggs' Drugs in Pregnancy and Lactation

LactMed

What acne drug is teratogenic?

Isotretinoin & topical retinoids

What antibiotics are teratogenic?

Quinolones & Tetracyclines

What anticoagulants are teratogenic?

Warfarin

What hormones are teratogenic?

Most, including estradiol, progesterone, raloxifene, duavee, testosterone, contraception

What migraine medications are teratogenic?

1. Dihydroergotamine

2. Ergotamine

What dyslipidemia, HF, htn medications are teratogenic?

Statins & RAAS inhibitors (ACEi, ARBS, aliskiren, Entresto)

Other common teratogens

- Hydroxyurea

- Lithium

- Methotrexate

- Misoprostol

- NSAIDs

- Paroxetine

- RIbavirin

- THalidomide

- Topiramate

- Weight loss drugs

- Valproic Acid

Preeclampsia

- Elevated blood pressure and evidence of organ damage, most often to the kidneys or liver

- ACOG & ADA guidelines recommend adding daily low-dose aspirin at the end of the first trimester for pregnant women at risk for preeclampsia (T1D or T2D)

Treating pain in pregnancy

Codeine and tramadol should not be used due to risk of excessive sleepiness, breathing difficulty and/or death especially in mothers taking codeine who were CYP450 2D6 ultra-rapid metabolizers

- Avoid opioids, even in small doses

Lactation Recommendations

AAP recommends babies be exclusively breastfed for the first 6 months of life, as long as it is mutually desired by mother and baby.

- Babies receiving breast milk partially or exclusively should receive 10mcg (400 IU) of vitamin D daily

- Breastfed babies require 1mg/kg daily iron during months 4-6

- Mothers who are breastfeeding should increase diet by 500 calories

Morning Sickness, Nausea & Vomiting during Pregnancy

- Lifestyle first

- Pyridoxine (B6) ± doxylamine (Bojesta, Diclegis)

- Possibly Ginger

GERD/Heartburn in Pregnancy

Lifestyle First:

- Eat smaller, more frequent meals, avoid foods that worsen GERD

- Elevate head of the bed and do not eat 3 hours prior to meals

- If lifestyle fails, use calcium antacids (Tums)

Flatulence in Pregnancy

Simethicone (Gas-X, Mylicon)

Constipation in Pregnancy

Lifestyle First:

- Increase fluid intake

- Increase dietary fiber intake

- Increase physical activity

- If lifestyle fails, fiber supplements (psyllium, calcium polycarbophil)

Cough, cold, allergies in pregnancy

First line: Cromolyn

Second line: First-generation antihistamines (Chlorpheniramine)

- If nasal steroids are needed for chronic allergy symptoms, all ICS are considered to be sage

- Budesonide (Rhinocort Allergy) and beclomethasone (Beconase AQ) are preferred

Pain in pregnancy

Acetaminophen first-line

- Avoid NSAIDS, including aspirin

Asthma in pregnancy

- Maintenance therapy: Budesonide is preferred (also preferred steroid for infants; respules are used in nebulizer)

- Rescue therapy: Inhaled albuterol

Iron Deficiency Anemia in pregnancy

- Supplemental iron, prenatal vitamins with iron

Hypertension in pregnancy

Labetalol, methyldopa or nifedipine

- ACEi, ARBs, Aliskiren, Entresto are all C/I

Diabetes in pregnancy

Insulin is preferred, metformin & glyburide are commonly used

Vaginal Fungal Infections in Pregnancy

Topical antifungals x 7 days

Urinary Tract Infections in Pregnancy

- Cephalexin 500mg q6h x7 days

- Ampicillin 500mg q6h x7 days

- Nitrofurantoin and Bactrim should be considered last line during the 1st trimester and should not be used in the last 2 weeks of pregnancy

- Must treat bacteriuria, even if asymptomatic

VTE in pregnancy

LMWH is preferred over UFH

- Prophylaxis pneumatic compression devices ± LMWH

Hypothyroidism in pregnancy

Levothyroxine (will require 30-50% dose increase during pregnancy)

Hyperthyroidism in pregnancy

If drugs ar enecessary (Graves' disease), use propylthiouracil in 1st trimester

- High risk for liver damage