Pregnancy-Breastfeeding Flashcards
What FDA drug reviewer stopped Thalidimide from reaching the US?
Francis Kelsie
Define Teratogen
Any agent that acts during embryonic or fetal development to produce a permanent alteration of form or function
Define Hadegen
agent that alters normal maturation or function of an organ
Define Trophogen
agent that alters growth
Criteria for a teratogen
Defect thoroughly characterized
Agent must cross the placenta
Biologically plausible association
Consistent epidemiological findings
Suspected agent causes a defect in an animal
Exposure must occur during a critical development period
Category A
Safe drugs (less than 1%)- levothyroxine, nistatin, pre natal vitamins, potassium supplements
Category B
animal reproduction studies show no evidence of harm
Category C
animal studies show that drug is teratogenic
Category D
Drug can cause harm to when administered to a pregnant woman
Category X
Drug is contraindicated in women who are or may become pregnant.
Downsides to the Category drug list?
Drugs in categories D and X (and even C) may carry similar risks
Implies that all drugs in a category carry the same risk
What are some mechanisms of birth defects?
Disruption of folic acid metabolism
Fetal genetic composition
Homeobox genes
Paternal exposure
What are homeobox genes?
Genes that have to activate at a certain point, tells the fetus how to organize itself
What drug can disrupt homeobox genes?
Retinoic acid
What is the risk of a birth defect with no drugs?
3%
What is the worst case risk of a birth defect with drugs?
6%
What class of antibiotics can enter breast milk?
tetracyclines
What time period may have a greater risk of drugs entering breast milk?
First few weeks of breastfeeding may be greater risk
Characteristics of drugs that enter breast milk?
have to be non-ionized
low molecular weight
Lipid soluble drugs pass more freely
pH of plasma and milk
Guidelines for women with a positive TOX screen for drugs of abuse
Breastfeeding can be supported in mothers who have:
- Abstained from the use of illegal drugs 90 days before giving birth
- Are enrolled, active and planning to continue in a substance abuse treatment program
- Have a negative drug screen at delivery
- Have received consistent prenatal care
- Have no other contraindications to breastfeeding
