Prescribing in Pregnancy

Question 1

State the overall guidance for prescribing in pregnancy

Answer 1

Lowest effective dose for shortest period using safest drug if maternal benefit > foetal risk

Question 2

Most drugs cross the placenta. True/False? What is the exception to this?

Answer 2

True

Except LMWH

Question 3

How might pharmacokinetics be affected by pregnancy?

Answer 3

Less absorption (morning sickness)
Increased distribuition (> plasma volume and fat)
Increased metabolism
Decreased binding (> free drug)
Increased elimination in renal-excreted drugs (>GFR)

Question 4

What should a female take 3 months prior to and in the first 3 months of pregnancy?

Answer 4

400 mcg folic acid

5mg folic acid in epileptics

Question 5

In which trimester is a baby at most risk from teratogenicity?

Answer 5

1st trimester (4th - 11th week)

Question 6

What teratogenic effect do ACEI/ARBs have?

Answer 6

Renal hypoplasia

Question 7

What teratogenic effect do antiepileptics have?

Answer 7

Cardiac defects
Facial and limb defects
Neural tube defects

Question 8

What teratogenic effect does lithium have?

Answer 8

Cardiac defects

Question 9

What teratogenic effect does methotrexate have?

Answer 9

Skeletal defects

Question 10

What teratogenic effect does warfarin have?

Answer 10

Limb and facial defects

Question 11

List adverse effects of medications on labour

Answer 11

Progress of labour
Adaptation of foetal ciculation
Suppression of foetal systems e.g. resp depression
Bleeding e.g. warfarin

Question 12

What are frequent seizures in pregnancy associated with in the child?

Answer 12

Lower IQ
Hypoxia
Bradycardia
Death

Question 13

Which antiepileptics should be avoided in pregnancy?

Answer 13

Valproate

Phenytoin

Question 14

Which class of diabetic drugs is not safe in pregnancy?

Answer 14

Sulfonylureas

Question 15

When does BP fall during pregnancy?

Answer 15

2nd trimester

Question 16

Which antihypertensives should be avoided in pregnancy?

Answer 16

ACEI/ARB

Question 17

List alternative antihypertensives that can be used in pregnancy

Answer 17

Labetalol
Methyldopa
Nifedipine MR

Question 18

Which medications are safest for use in nausea and vomiting?

Answer 18

Cyclizine

Question 19

Which medications are safest for use in UTI?

Answer 19

Nitrofurantoin
Cefalexin
Trimethoprim in 3rd trimester

Question 20

Which medications are safest for use in pain?

Answer 20

Paracetamol

Question 21

Which medications are safest for use in heartburn?

Answer 21

Antacids

Question 22

Which drug is used to treat and prevent VTE in pregnancy?

Answer 22

LMW Heparin

Question 23

Why is warfarin contraindicated in early and late pregnancy respectively?

Answer 23

Teratogenic

Risk of haemorrhage during delivery

Question 24

Most drugs enter breast milk. True/ False?

Answer 24

True

Especially small molecules, lipophillic drugs

Question 25

List some common drugs that can concentrate in breastmilk and their effect

Answer 25

Phenobarbitone (suckling difficulty)
Amiodarone (hypothyroidism)
Cytotoxics (bone marrow suppression)
BZDs (drowsiness)
Bromocriptine (suppresses lactation)

Question 26

Which antibiotic given in pregnancy or early childhood can cause blue staining of teeth?

Answer 26

Tetracycline

Question 27

List facial features of foetal alcoholic syndrome

Answer 27

Short palpable fissures
Flat midface
Epicanthal folds
Short nose, low bridge
Indistinct philtrum
Thin upper lip

Question 28

Which antiepileptic can cause cleft lip/palate?

Answer 28

Phenytoin

Question 29

Which antiepileptic is associated with neural tube defects?

Answer 29

Valproate