Preg & Breast - L2 Drugs Flashcards
(15 cards)
Pain relief -
Morphine
Morphine – strong opioid of choice in Breastfeeding – lowest effective dose & only short term – use non-opioids alongside to reduce need for morphine. Infant monitoring required
Breastfeeding: Gabapentin/Pregabalin
Gabapentin & pregabalin both lack data to support use in breastfeeding
Breastfeeding & Antibiotics: Nitrofurantoin
Nitrofurantoin: Excretion into breastmilk is clinically insignificant. Not to be used in premature infants, younger than 2 weeks of age, G6PD deficiency, jaundice – risk of neonatal haemolysis.
Breastfeeding & Antibiotics: Metronidazole
Metronidazole:
Excreted in moderate amounts (low molecular weight; low protein binding), fully orally bioavailable, short half-life, minimal risk accumulation.
Fine for short courses, monitor GI effects.
Premature or new-borns are unable to metabolize metronidazole well so use minimum effective dose or see alternative.
Breastfeeding & Antibiotics: Macrolides (Erythromycin & Clarithromycin)
Macrolides:
Erythromycin - Excreted in negligible amounts, but potential risk of hypertrophic pyloric stenosis – avoid in 1st month life
Clarithromycin - Excreted in negligible amounts, low risk – monitor for GI S/Es
Breastfeeding & Antidepressants – SSRIs, Tricyclics & etc
SSRI’s: Paroxetine & Sertraline are SSRI’s of choice due to shorter half-lives & pass into milk in smaller amounts compared to others
Breastfeeding & Antidepressants: Tricyclics - 3
- Tricyclics: Imipramine & nortriptyline are TCAs of choice as less sedating & reduce risk of infant sedation.
- They undergo 1st pass metabolism, which lowers how much the infant absorbs.
- Long half-lives could result in accumulation & increased S/Es
Breastfeeding & Anxiolytics – 4
- Use short-acting benzodiazepine (e.g. Lorazepam, oxazepam) at lowest effective dose
- Diazepam – Significant amount excreted in milk. S/E: risk of sedation & poor sucking in infant
- Use ‘Z’ drugs for sleeping disorders – zopiclone & zolpidem – again short half-life & small amounts in breastmilk
- Withdrawal effects may occur in the infant is mother suddenly stops breastfeeding
Breastfeeding & Antipsychotics – Haloperidol, Olanzapine
Haloperidol: Excreted in milk in variable amounts, so could be clinically significant
Olanzapine: 20mg or less is low in milk. Long half-life, need to monitor signs of accumulation – sedation, poor feeding etc.
Breastfeeding & Antipsychotics - Lithium
Lithium: Excreted in milk in moderate amounts. Regular checks on infant for signs of lithium toxicity – monitor poor feeding, poor weight gain, changes in behaviour, diarrhoea, tremor.
Breastfeeding & Anti-coagulants – Heparins, Warfarin, DOACs, Rivaroxaban, Apixaban & Edoxaban
Monitoring infant: Bruising & bleeding – in vomit, urine, stools
Heparins: LMWH/Unfractionated safe as large MW so little getting into breast milk. Inactivated in GIT, unlikely to enterinfant’s system
Warfarin: Oral anticoagulant of choice in breastfeeding – Very highly protein bound so less ‘free’ drug to pass into milk
DOAC’s: All DOAC’s may pass into breast milk. e.g. Dabigatran is largest DOAC & has a large volume of distribution, so expected to enter breast milk in low amounts, but low PO BA, so infant unlikely to absorb clinically significant amounts
Rivaroxaban: Large volume of distribution & high percentage of protein binding – very small passage in to milk
Apixaban & Edoxaban are not recommended: Apixaban levels in milk appear to be quite high.
Breastfeeding & Anti-hypertensives - Beta-Blockers
Beta-Blockers: Labetalol, metoprolol & propranolol are beta-blockers of choice to use during breastfeeding
Very small amounts get into milk and they have shorter half-lives to lower risk of accumulation.
Atenolol – excreted in small to moderate amounts
Bisoprolol – used with caution due to potential for accumulation (low protein binding & high PO BA suggests excretion into breast milk & absorbtion by infant. Half-Life 9-12 hours & 50% excreted in urine so potential for accumulation)
Breastfeeding & Anti-hypertensives - Calcium-Channel Blockers
Calcium-Channel blockers - Nifedipine & Verapamil are the preferred choice
ACE Inhibitors - 2
- Enalapril is ACEi of choice in breastfeeding – active metabolite is poorly absorbed PO & negligible amounts in milk
- Most ACEi metabolised to active metabolite which is poorly absorbed PO, so metabolite unlikely to be absorbed by infant
e.g.
A. Lisinopril – is active compound – no info on excretion in milk
B. Perindopril – long half-life (30 to 120hrs) so risk of accumulation
C. Ramipril – limited data show minimal amounts in milk
Breastfeeding & Anti-Epileptics – Carbamazepine, Phenytoin, Topiramate & Valproate
Levetiracetam: infant levels low or undetectable. Monitor for infant drowsiness
Lamotrigine: Significant in milk – long-half life increases risk of accumulation. Monitor for rash, apnoea, drowsiness & poor feeding
Carbamazepine & Phhenytoin: Very low risk & compatible with breastfeeding - Excreted in small amounts
Topiramate: Very low risk, moderate amounts excreted into breast milk, but no observed effects in infant
Valproate: Risk of significant birth defects & developmental disorders, so not recommended to be used in women of child-bearing age
