Pharmacology in Pregnancy and Breastfeeding Flashcards
Why could a woman be on medicines during pregnancy, childbirth and lactation?
Hypertension Asthma Epilepsy Migraine Mental health disorders Long-term anticoagulant therapy use
What are the routes of drug administration?
Oral
Intramuscular
Inhalation
Why is the oral route more complicated in pregnancy?
Nausea/vomiting
Increase in gastric emptying and gut motility
Why is the intramuscular route more complicated in pregnancy?
Blood flow may be increased, so absorption may also increase using this route
Why is inhalation more complicated in pregnancy?
Increased cardiac output and decreased tidal volume may cause increased absorption of inhaled drugs
How will a greater dilution of plasma affect the relative amount of plasma proteins?
Decreased
What affect does pregnancy have on GFR?
Increased - leads to increased excretion of many drugs
Can reduce plasma concentration and necessitate an increase in dose of renally cleared drugs
What are the functions of the placenta?
Attach the fetus to the uterine wall
Provide nutrients to the fetus
Allow the fetus to transfer waste products to the mother’s blood
When is teratogenicity a concern?
First trimester
When is fetotoxicity a concern?
Second and third trimester
What is folate antagonism?
Key process in DNA formation and new cell production
What are the mechanisms of folate antagonism?
Block the conversion of folate to THF by binding irreversibly to the enzyme
Block other enzymes in the pathway
What are the defects from folate antagonism?
Neural tube, oro-facial or limb defects
Which drugs can cause neural cell crest disruption?
Retinoid drugs (eg isotretinoin)
What problems are associated with neural crest cell disruption
Aortic arch anomalies Ventricular septal defects Craniofacial malformations Oesophageal atresia Pharyngeal gland abnormalities
What are possible fetotoxicity issues later in pregnancy?
Growth retardation Structural malformations Fetal death Functional impairment Carcinogenesis
What effects do anticonvulsants have on the foetus?
Valproate is associated with neural tube defects, as is carbamazepine and phenytoin
What effects do anticoagulants have on the foetus?
Warfarin is associated with haemorrhage in the fetus, as well as multiple malformations in the central nervous system and skeletal system
What effects do antihypertensive agents have on the foetus?
ACE inhibitors cause renal damage and may restrict normal growth patterns in the unborn child
What effects do NSAIDs have on the foetus?
Premature closure of the ductus arteriosus
What effects does alcohol have on the foetus?
Foetal alcohol syndrome
What effects do retinoids have on the foetus?
Ear, CNS, cardiovascular, and skeletal disorders
What are the symptoms of foetal alcohol syndrome?
Small head Poor growth Distinctive facial features Cerebral palsy Learning difficulties Mood, attention, or behavioural problems Hearing and vision problems
Which types of drugs should be avoided whilst breast feeding?
Cytotoxics Immunosuppressants Anti-convulsants (not all) Drugs of abuse Amiodarone Lithium Radio-iodine
