CS1

What is the neonatal period of life?

first 28 days of life

What are the risk of drugs at neonatal age?

the risk of toxicity is increased by reduced drug clearance and differing target organ sensitivity

What injections should be avoided in children?

intramuscular due to being painful

What are the two most common ways dosing is calculated for children?

Total body weight, specific age ranges

What are other less common ways dosing is calculated?

Body surface area, Corrected gestational age for preterm neonates, ideal body weight

What is defined as a child in the BNF?

1 month to 17 years

What is premature defined as?

born before 37 weeks gestation

What drugs may be dosed via body surface area?

Chemotherapeutic drugs

Why is important to identify if a child is obese?

as body composition and physiological changes in obesity can affect drug pharmacokinetics and the distribution of drugs into tissues, risk of overdose if TBW is used for some drugs

What can drugs do to the foetus in the first trimester?

congenital malformations (teratogenesis)

What period of time is the biggest risk of congenital malformations (teratogenesis)?

third to the eleventh week of pregnancy

What can drugs affect un the 2nd and 3rd trimesters?

growth or functional development of the foetus

What is the risk with giving drugs before term or during labour?

Can have adverse effects on labour or on the neonate after delivery

What period of development is the pre-embryonic phase?

First 17 days

What can happen in the pre-embryonic phase?

Exposure to drugs will result in survival or death of the embryo (all or nothing principle)

What period of time is the embryonic phase?

18 to 55 days

What can happen in the embryonic phase?

embryo will be most vulnerable to teratogens during this time

What period of time is the foetal period?

56 days until birth

What happens during the foetal period?

Organs continue to develop, drugs can affect growth, functional abnormalities such a deafness may occur during this period

When is a pregnancy considered full term?

lasted 39 to 41 weeks.

How long is late term in pregnancy?

41 weeks

How long is post term in pregnancy?

42 weeks

What is considered early term in pregnancy?

Before 39 weeks

How may absorption be changed in pregnancy?

Medication may be vomited before it can be absorbed

Medication timing may change or co-administration with ant-emetic

Progesterone + other hormones slow gastric emptying decreasing absorption and bioavailability

How may distribution change in pregnancy?

Plasma volume increases progressively

Total body water increases by 8 litres, decreased plasma proteins increased levels of free drug

Regional blood flow changes

How may metabolism change in pregnancy?

Progesterone can cause hepatic enzyme changes

How may elimination change during pregnancy?

Higher cardiac output up to 20% by 8th week of pregnancy, GFR and plasma flow increases, affect on renally excreted drugs

What is child bearing age considered?

15-45 years

What age is the use of contraception necessary until?

55

What is the risk of birth defect for women taking valproate?

1 in 10

What birth defects are seen in women taking valproate?

Spina bifida

Facial and skull malformations

Malformations of the limbs, heart, kidney, urinary tract and sexual organs.

What is the risk of developmental problems in pregnant women taking valproate?

3 to 4 in every 10

What developmental problems may arise with pregnant women taking valproate?

• Being late in learning to walk and talk

• Lower intelligence than other children of the same age

• Poor speech and language skills

• Memory problems.

What does the BNF identify regarding drugs and pregnancy?

Harmful effects in pregnancy which trimester, what drugs are not known to be harmful in pregnancy, human and animal data where appropriate

When is the first pregnancy scan done?

8-14 weeks (the ‘dating’ scan)

When is the 2nd pregnancy scan done?

18-21 weeks (‘anomaly’ or ’mid-pregnancy’ scan)

What other tests are done during pregnancy?

Blood test, bp, urine for infection and signs of infection, oral glucose tolerance test

What may protein found in a pregnant persons urine mean?

an infection that needs to be treated

be a sign of pre-eclampsia .

What problems can pre-eclampsia cause?

Seizures, can be life threatening, can affect the growth and health of the baby

What could be a sign of pre-eclampsia?

rise in blood pressure later in pregnancy

What monitoring would be appropriate with a pregnant patient with pre-existing diabetes?

glucose tolerance decreases so

• More frequent blood glucose monitoring

• More frequent doses of insulin or metformin

Why would monitoring be appropriate with a pregnant patient with pre-existing epilepsy?

many antiepileptic drugs are teratogenic

An increases risk of folate deficiency

Why would monitoring be appropriate with a pregnant patient with pre-existing high BP?

risk of pre-eclampsia

May need to switch BP medication during pregnancy

Why would monitoring be appropriate with a pregnant patient with pre-existing mental health conditions?

many drugs are not ideal in pregnancy but would need to make a risk benefit assessment

What should the conversation about stopping antidepressants during pregnancy?

Risk of stopping abruptly vs not treating depression, may still be a teratogenic risk even if medication is stopped immediately, what other treatment options are available

What is the risk of spontaneous abortion in pregnancy?

10 to 20 out of every 100 pregnancies.

What is the risk of risk of spontaneous major malformation?

1 to 40

Why is breast feeding beneficial?

the immunological and nutritional value of breast milk to the infant is greater than that of formula feeds.

What are the concerns about breastmilk carry drugs to the infant?

amount of drug or active metabolite of the drug delivered to the infant, infant pharmacokinetics, the affect of the drug on the infant

Describe the first 72 hours post partum with medications and breast milk?

Open cellular gaps in alveolar allow for passage of immunoglobulins, gaps enable free movement of medications in breast milk, the absolute drug dose is low due to small volume being consumed?

Describe the after first 72 hours post partum with medications and breast milk?

The alveolar cellular gaps close with prolactin, preventing free movement of drugs into breastmilk, medication now needs to pass through cell membrane, molecule size now affects ease of passage into milk

How can phenobarbital affect breast feeding?

can inhibit the sucking reflex in infants by causing drowsiness

How can bromocriptine affect breast feeding?

can affect lactation (used for the suppression and prevention of lactation)

How can metronidazole affect breast feeding?

safe to use in breastfeeding, can give the milk a bitter taste which makes it less palatable to the baby

What information do you need to collect when talking to parent about breast feeding?

• Which medication, dose, frequency, route, duration?

• Was it taken in pregnancy?

• Other options?

• Is breastfeeding established?

• Gestation at birth and age now

• Weight

• Medical history

• Babies medication

• Any issues with sucking e.g. tongue tie?

• Any known allergies?

What does the BNF tell us about the use of drugs in breast feeding?

caution or are contra-indicated in breast-feeding,

an be given to the mother during breastfeeding because they are present in milk in amounts which are too small to be harmful

might be present in milk in significant amount but are not known to be harmful

Where care is needed when prescribing in breast-feeding,

What should be remembered about drugs and breast feeding?

insufficient evidence is available to provide guidance and it is advisable to administer only essential drugs to a mother during breast-feeding

Absence of information does not imply safety