Drugs in pregnancy and at the extremes of age Flashcards
How is absorption affected in pregnancy
Gastric emptying delayed for oral preparations
How is distribution affected in pregnancy
Total body water and fat increases
Lower conc. of water soluble and lipid soluble drugs
How is metabolism affected in pregnancy
Increase in clearance of drugs - depens on liver enzyme activity - phenytoin , theophylline
How is elimination affected in pregnancy
Increase in renal plasma flow doubling the elimation of renally cleared drugs
Factors that can influence placental transfer
Lipid/ water solubility
Molecular size
Protein binding
Metabolism
What drugs to watch for in pregnancy
7 As and DMARDs
ACEi/ARBs Anticonvulsants Antibiotics Antipsychotics Antithyroid Anticoagulant abuse of drugs DMARDs/cytotoxics
treatment for nausea and vomiting in pregnancy
1st line - promethazine, cyclizine, prochloroperazine
2nd line-metoclopamide, ondansetron
Treatment for asthma in pregnancy
Predinsolone
Hypertension in pregnancy
Older drugs labetalol, methyldopa, nifedipine
How to deal with anticoagulation in pregnancy
LMW heparin
Avoid warfarin
DOACs- avoid
How is absorption affected in the neonate
Skin SA is greater so there is a greater absorption of topical agents
Intramuscular - absorption impaired reduced mass
Rectal absorption is relatively efficient
How is distribution affected in the neonate
Body water % increases
Albumin binding decreases
How is metabolism affected in the neonate
impaired oxidation - increase conc of drugs
How is elimination affected in the neonate
GF and reaborption are impaired
6 months - renal function usually normal
How is absorption affect in the elderly
PO - delayed - reduced motility and blood flow
