8 - Drugs In Pregnancy Flashcards
The required Daltons for drugs to cross the placenta:
Drugs with <1000 D cross the placenta (500> D cross easily)
Main determinant of the drug concentration in the fetus:
Mother’s blood concentration
Other factors:
Lipid solubility and protein binding
Placental blood flow
Main determinant of the drug concentration in the milk:
Maternal serum concentration
Fetal age and drugs effect:
— Unlikely before 20d after fertilization
— Teratogensis during organogenesis [between 20–56d after fertilization + 34–69d after LMP] —> Cause anatomical defects and abortion
— Teratogensis unlikely after organogenesis [2nd—3rd trimester] —> instead it may alter the growth and function of fetal organs and tissues
Category B Abs:
Penicillin, cephalosporins, macrolides [Azithromycin and erythromycin], nitrofurantoin, metronidazole, vancomycin
Nitrofurantoin use and S/E:
Used to treat UTI in pregnant, and carry a risk of hemolytic anemia if used in late pregnancy
Vancomycin S/E:
Ototoxicity
Category C Abs:
Aminoglycosides [Neo and Tobramycin], Quinolones, trimethoprim, chloramphenicol
Chloramphenicol S/E:
Gray baby syndrome
Category D abs:
Tetracycline, aminglycocides [Streptomycin and gentamicin]
Antivirals B and C:
B —> Acyclovir [For Varicella]
C —> Amantadine
Category B Antifungal:
1– Amphotericin [DOC for pregnancy fungal infections]
2– Terbinafine [For Onychomycosis]
Category C antifungals:
1– Ketoconazole
2– Fluconazole
Category D NSAIDS:
Aspirin, ibuprofen, diclofenac
Category D NSAIDS S/E:
Premature closure of Ductus arteriosus
