Drug Use During Lactation Flashcards
What is the best form of nutrition for young infants?
Breast milk
Mothers should breast feed exclusively for ____, and continue until at least ___ while other foods are introduced.
6 months; 12 months
Breast feeding provides:
1) Protection of the infant against gastric, respiratory, and urinary tract infections.
2) Reduction in the rate of obesity, and juvenile onset diabetes mellitus.
3) Reduction in the rate of atopic diseases.
Maternal benefits of beast feeding include:
1) Reduced risk of developing pre-menopausal breast cancer
2) Strengthens the mother-infant bond
The drug dose ingested by the infant via breast milk ___(usually/rarely) causes adverse effects.
Rarely
Almost all drugs enter breast milk by:
Passive diffusion through the lipid membrane of the alveolar cells of the breast.
Drugs that enter the breast milk should be:
1) Un-ionized
2) Not protein bound
Factors affecting rate and extent of passive diffusion of drug to breast milk include:
1) Maternal plasma drug level
2) Physiological differences between plasma and milk
3) Physicochemical properties of the drug
What is the pH of breast milk?
6.8 – 7.0
In which ways does breast milk differ from blood?
1) Lower pH
2) Lowering buffering capacity
3) Higher fat content
What are the drug parameters affecting the extent of transfer
into milk?
1) pKa
2) Protein binding
3) Lipophilicity
4) Molecular weight
What does the pKa determine?
Drug ionization at a given pH
Do highly ionized drugs tend to concentrate in milk?
No
Is Erythromycin acidic or basic?
Basic
For basic drugs, a greater fraction will be ionized at a(n) ___(basic/acidic) pH. What does this mean?
Acidic; That the milk compartment tends to trap weak bases.
Is Penicillin acidic or basic?
Acidic
Acidic drugs are more ionized at ___(lower/higher) pH values and will be trapped in the __ compartment.
Higher; Plasma
Drugs with higher pKa values generally have higher ____.
Milk/plasma ratios
Is Warfarin highly bound to plasma proteins?
Yes
Drugs that are highly bound to plasma proteins (warfarin) are likely to be retained in the __.
Plasma; because there is lower protein content in milk (~1%).
__-active drugs usually cross to breast milk.
CNS
Do water-soluble drugs effectively cross the alveolar epithelium of the breast?
No
Drugs with what molecular weight readily pass into the milk?
Low molecular weight (<200)
How do low molecular weight drugs pass into the breast milk?
Through small pores in the cell wall of alveolar cells
How do high molecular weight drugs pass into the breast milk?
By dissolving in the lipid layer
Which are virtually excluded from passing into breast milk?
Protein molecules (very large molecular weights >6000 daltons)
Drugs that pass minimally to breast milk would be:
1) Acidic drugs
2) Drugs with high plasma protein binding
3) Drugs with low-to-moderate lipophilicity
What is an example of a drug that would pass minimally into breastmilk?
Most NSAIDs
Drugs that pass significantly to breast milk would be:
1) Basic drugs
2) Drugs with low plasma protein binding
3) drugs with relatively high lipophilicity
What is an example of a drug that would pass significantly into breastmilk?
Sotalol
Why is there enhanced passage of drugs into breastmilk in the first few days of life?
Because in the first week, large gaps exist between alveolar cells
The large gaps between the alveolar cells close under the influence of:
Prolactin
What is colustrum?
The first breast milk released in the first 2 days after giving birth
Colustrum has high amounts of:
1) Immunoglobulins
2) Maternal lymphocytes
3) Maternal macrophages
Greater amounts of drugs are present in colustrum, but the amounts received by infants are low. Why?
Because of the low volume of colustrum produced
Which drug is actively pumped into breast milk?
Iodides
Which drug is found in breast milk in high concentrations?
Iodides
Which factors should be considered when assessing the risk to the infant?
1) Inherent toxicity of the drug
2) Multiple maternal therapy with drugs having similar adverse effects
3) Active metabolites
4) Drugs with long half-lives
5) Gestational age
6) Maternal drug regimen
Which drugs are contraindicated during lactation for being hazardous to infants?
1) Antiarrhythmic drugs
2) Anticholinergic drugs
3) Anti-infective drugs
4) CNS stimulants
5) Cytotoxic agents
6) Illicit substances
7) Immunosuppressants
8) Thalidomide
9) Lithium
10) MAOIs
11) Radioactive substances
12) Skeletal muscle relaxants
13) Tetracyclines
14) Tricyclic antidepressants
15) Retinoic acid derivatives
Anticonvulsants should not be given with:
Psychotropic drugs
What is a drug with active metabolites?
Benzodiazepines
Fluoxetine has a ___(short/long) half-life
Long
Why are drugs with active metabolites contraindicated during lactation?
They may prolong infant drug exposure and lead to drug
accumulation.
Premature infants are more
susceptible to drugs because of:
Low clearance
What are some strategies to reduce the risk of drugs in breast fed infants?
1) Choose medications considered safe for use in infants
2) Give the maternal dose immediately after the infant has been fed
3) If the mother is receiving a single dose of a hazardous material (radiopharmaceuticals),
avoid breast feeding and resume after a reasonable washout period
4) Administer once-daily meds before the infant’s longest sleep
period to increase the interval to next feeding.
5) Breastfeeding mothers should avoid self-medication
6) When drug use is indicated, the lowest effective dose should be used for the shortest possible period of time.
7) Simplify maternal regimen as much as possible
8) New drugs are best avoided if a therapeutic equivalent is available for which data on safe use during lactation is available
9) Monitor exposed infants for adverse effects.
10) During short-term drug therapy, and if the medication is NOT compatible with breastfeeding, the mother can pump milk out and discard it to preserve here milk-producing capability
What is the usual washout period for drugs?
5 half-lives
Which drugs should be selected during lactation?
1) Short half-lives
2) High protein binding
______ are at greater risk of developing adverse effects to drugs after exposure via breast milk.
Neonates and premature infants
Gastric emptying time in neonates and premature infants is ___(shortened/prolonged) and may alter drug absorption.
Prolonged
Protein binding in neonates and premature infants is ___(increased/decreased).
Decreased
Do neonates and premature infants have higher or lower total body water?
Higher
Oxazepam is eliminated by:
Direct conjugation with glucuronide
Neonates and premature infants should not be exposed to oxazepam. Why?
Because their conjugation capacity is deficient
What does a Glucose-6 phosphate dehydrogenase (G6PD) deficiency do to erthyrocytes?
Makes them more susceptible to oxidative stress = hemolysis
Should you breastfeed with a G6PD deficiency if you’re taking hemolysis-inducing drugs?
No, even small amounts of the drug can cause hemolysis
What does a high intake of alcohol in breastfeeding mothers do?
1) Decreases milk let down reflex
2) Disrupts nursing
3) Causes sedation, fluid retention, and hormone imbalances in infants.
What does nicotine do during lactation?
Decreases basal prolactin production
Caffeine appears in breast milk __(slowly/rapidly) after maternal intake.
Rapidly
10 or more cups of coffee per day by the mother causes what in breast fed infants?
1) Fussiness
2) Jitteriness
3) Poor sleep patterns
Preterm and newborn infants metabolize caffeine ___(rapidly/slowly) and are at increased risk.
Slowly
Which drugs are the main cause of effects on milk production?
Drugs that affect dopamine activity
Cabergoline is a dopamine __(agonist/antagonist).
Agonist
Dopamine agonists __(increase/decrease) milk production.
Decrease
Domperidone is a dopamine __(agonist/antagonist).
Antagonist
Dopamine antagonists
__(increase/decrease) milk production
Increase
Early postpartum use of ___ may reduce the volume of milk.
Estrogens
Milk production can be abolished by the use of:
1) Estrogens
2) Oral contraceptives
Breast milk production can be increased by:
Metoclopramide
Metoclopramide stimulates ___ secretion
Prolactin
Can we give Amantadine during lactation?
No, it decreases milk production
What is Fenugreek?
A botanical galactagogue
Does Fenugreek increase or decrease milk production?
Increase
Do botanical galactagogues increase or decrease milk production?
Increase
Which botanical galactagogues are common?
1) Fenugreek
2) Fennel
3) Anise
4) Milk thistle
5) Barley
