Prescribing in Pregnancy Flashcards
When are US scans for microcephaly and short limbs carried out?
usually after 22 weeks
What type of drug doesn’t cross the placenta?
large molecular weight eg heparin
What type of drug crosses the placenta quickly?
small, lipid soluble drugs
How is absorption of drugs affected by pregnnacy?
morning sickness
How is distribution of drugs affected by pregnancy?
increased- increased plasma volumes and fat stores; decreased protein binding- increased free drug
How is metabolism of drugs affected by pregnnacy?
increased liver metabolism of some drugs eg phenytoin
How is elimination of drugs affected by pregnancy?
elimination of renally excreted drugs increases- increased GFR
When is the period of greatest teratogenic risk?
4th-11th weeks
What type of development occurs during the 1st trimester?
organogenesis
What problems can ACEi and ARBs cause?
renal hypoplasia
What problems can androgens cause?
virilisation of femal foetus
What problems can antiepileptics cause?
cardiacl faical; limb and NTDs
What problems can cytotoxic drugs cause?
multiple defects; abortion
What problems can methotrexate cause?
skeletal defects
what problems can retinoids cause?
ear; CVS and skeletal defects
What problems can warfarin cause?
limb and facial defects
What type of development occurs during hte 2nd and 3rd trimesters?
growth of fetus; functional development
What problems do drugs during the 2nd and 3rd trimesters cause?
intellectual impriamnet and behavioural abnormalities
What problem did diethylstilbestrol cause?
vaginal adenocarcinoma in teenagers
How does seizure frequency during pregnnacy change for epilpetics?
increased in 10% women
Why does seizure frequency increase during women?
non-compliance; changes in plasma con. of drugs
What are frequent seizures during pregnancy associated with?
lower verbal IQ; hypoxia; bradycardia; IUD; maternal death
What epileptic drugs should really be avoided in pregnnacy?
valproate and phenytoin
What hypoglycaemic drug is not safe in pregnnacy?
SUs
What effect do beta blockers have on the fetus in late pregnnacy?
inhibit fetal growth
What drug should be used to treat N and V?
cyclizine
What drugs should be given for UTI in 1st and 2nd trimesters in pregnancy?
nitrofurantoin and cefalexin
What drugs should be given for UTI in the 3rd trimester?
trimethoprim
What is the risk of VTE in pregnnacy?
10x risk
Who should receive thromboprophylaxis with LMWH?
2 or more RF- obesity; age >35; smoking; para >3; prev DVT; C/S
What is the make up of foremilk?
protein rich
What is the make up of hindmilke?
higher fat content
What happens with longer feeds in terms of drugs?
longer feeds result in higher amounts of fat soluble drugs in mlik
What problems can phenobarbitone cause if taken whilst breastfeeding?
suckling difficulties
What problem can amiodarone cause if taken whilst breastfeeding?
neonatal hypothyroidism
What problem do cytotoxics cause if taken during breastfeeding?
bone marrow suppression
What problem can BZDs cause whilst breastfeeding?
drowsiness
What problem does bromocriptine cause whilst breastfeeding?
suppresses lactation
What problem does tetracycline cause if taken during pregnnacy or early childhood?
staining of bones and teeth
Which epileptic drug is particularly associated with cleft lip and palate?
phenytoin
Who should be given electrical stimulation for pelvic floor?
muscle strength grade 2 or less
Who should have physio input after delivery?
women who have had forceps delivery or 3rd/4th degree tear
