Meds in Pregnancy Flashcards
1979-2015 FDA pregnancy categories established A-D, X, and N…what does each mean?
A= no risk to fetus in any trimester
B = no risk shown in animal studies, but no studies in pregnant women
C = animal studies have shown AEs, but no studies in humans, potential benefits may warrant use despite risks
D = positive evidence of human fetal risk, but can use if benefits outweighs the risk
X = don’t use unless absolutely necessary
N = not classified
New FDA labeling uses three subsections for risk: pregnancy, lactation, females/males reproductive potential…explain each
Pregnancy: use of drug in pregnant women (dosing, potential risk to fetus, registry about risk summary, clinical considerations, and data)
Lactation: risk summary, clinical considerations, and data
F/M Repro Potential: pregnancy testing, contraception, infertility related to drug
Decreased gastric emptying/SI motility, increase in gastric pH, N/V, inhalation drugs, IM delivery
Pharmacokinetic changes in absorption (study)
Total body water increased up to 8L, albumin concentration, body fat increased by approx 4kg
Pharmacokinetic changes in distribution (study)
P450 system can be induced or inhibited by estrogen and progesterone (higher or lower rate of….)
Metabolism (P450 system)
Renal blood flow increased by 60-80%, GFR increased by 50% (meaning increased…)
Elimination
Dependent on placental blood flow, some don’t cross placenta, large molecular weight don’t cross, metabolism in immature fetal liver/placenta?
Pharmacokinetic changes in fetal-placental drug transfer
Due to fetal circulation bypassing fetal liver to heart and brain, elimination low through maternal compartment, acidic fetal plasma favors movement of lipophilic drugs form mom to fetus?
Pharmacokinetic changes in fetal drug accumulation
Non-pharm, ginger, doxylamine, stopping use of diphenhydramine/meclizine, add metoclopromide, switch antihistamines to promethazine or procholperazine, add ondansetron or glucocorticoids
What are these for?
Nausea in pregnancy
No known safety concerns, reduces nausea but not vomiting?
Ginger
Improves mild-moderate nausea, but not vomiting, no teratogenic concerns, but can cause sensory neuropathy at high doses?
Pyridoxine (Vitamin B6)
Combo of these tow used for nausea and vomiting, moderately effective, removed in 1983 due to teratogenic concerns but there’s scientific basis for this/show safe use in pregnancy?
Doxylamine and pyridoxine combo
Used for persistent N/V, discontinue use of doxylamine prior to starting these
Meclizine and diphenhydramine
Some risk of cleft pallet malformation with Meclizine
Dopamine antagonists for persistent N/V?
Metoclopromide (long term use could see tardive dyskinesia, dystonia)
Promethazine (sedation and dystonia, lowers seizure threshold)
Prochlorperazine (some case reports of malformations, not conclusive trials)
Two serotonin antagonists for persistent N/V?
Ondansetron (controversial…two trials showed a bunch of risks)
Granisetron (no safety data in pregnancy)
Used in short course for refractory N/V, avoid in 1st trimester due to cleft palate risk, exaggerated AEs in pregnancy?
Glucocorticoids
Promethazine and Metoclopramide are probably more efficacious
What do we do for GE reflux in preg?
Smaller meals, less spicy, elevate bed, antacids, sucralfate, H2 antagonists, PPI
Safe in pregnancy and lactation, can be constipating (aluminum and calcium) or diarrhea (magnesium)
Antacids
Not well absorbed, likely safe, forms viscous paste-like gastric lining?
Sucralfate
Ranitidine and cimetidine have the most safety data, excreted in breast milk?
H2As
Likely safe in pregnancy, excreted in breast milk but destroyed by baby’s stomach?
PPIs: omeprazole, lansoprazole, pantoprazole have most data
The one absolute NONO drug in pregnancy for reflux?
Bismuth Subsalicylate (pepto-bismol)
Meds in pregnancy for constipation?
Fiber, docusate, mag hydroxide or lactulose or bisacodyl for refractory cases
Not shown to be teratogenic in animals, but human studies are inconclusive, drug for diarrhea?
Loperamide
Cannot use NSAIDs or ASA in preg for pain, so use what?
Acetaminophen, but there is possibly an ADHD risk
Antihistamines preferred in preg?
1st: diphenhydramine and chlorpheniramine
2nd: fexofenadine, loratadine, cetirizine
For cough suppressants, codeine, hydrocodone, dextromethorphan can cause withdrawal symptoms in baby with long-term use…one large trial correlated what with opioid use?
Congenital anomalies
Also don’t use Guaifenisin (inguinal hernias)
For rhinorrhea, sneezing, throat pain, best to use what?
Clean water spray, cepacol
Decongestant: short term use of intranasal oxymetazoline may be beneficial, but not well studied
For the Abx, look at the chart (slide 34) and know which ones to absolutely not use
Slide 34
Three anti-fungal drugs that are absolutely NOs?
Butoconazole and Miconazole/Ticonazole
Best anti-virals during pregnancy?
Valacyclovir (Valtrex) is considered safe
In terms of topical creams/ointments, what two groups do we absolutely not use?
High-potency steroids and Tretinoin (Retinoid/Retin A)
Begins 20th week after pregnancy (typically 3rd trimester) - pregnancy induced HTN presents with persistent headaches, blurred vision, ab pain, light sensitivity
Preeclampsia
Lifestyle changes work, for meds we use Methyldopa or Labetalol
Urgent/emergent: hydralazine, labetalol, nifedipine
Very serious complication of preeclampsia characterized by one or more seizures during pregnancy…if untreated can kill…presents with seizures, swelling, sudden weight gain, coma, brain damage, death
Eclampsia, DOC is Magnesium Sulfate IV, IV fluids
Gestational DM if left untreated = large birth weight, premature delivery, C-section, increased risk of death of fetus, how we treat?
Insulin…need specialized care though b/c it’s complicated (all are cat B except glaring and glulisine which are C)
Glyburide and Metformin are both cat B, but lack long-term safety data
NTD risk increased with family history, certain anti-seizure meds, obesity, diabetes
How do we prevent?
400-1000mcg folic acid/day before
1000mcg folic acid/day during preg
Prior preg w/NTD: 4mg folic acid at least 1 month before peg and throughout 1st trimester
Anemia (IDA, folate-deficiency anemia, Vit B12 deficiency anemia), how we treat?
Iron rich food, non-animal protein, recommended iron daily allowance for pregnancy is 27 mg/day
Supplements: ferrous fumarate, ferrous sulfate, ferrous gluconate
Meds in lactation, don’t take right before breastfeeding
If med is not safe for infant, discontinue if possible, if short term pump and dump, if long term switch to formula
