Medications in Lactation

See Also

Medications in Pregnancy

Approach

Assess benefit versus risk for medication
1. Safest treatment in Lactation is non-medication therapy
2. Topical Medications are typically safer than systemic medications (except those applied in the region of the nipple)
Choose medications safe for Lactation (see categorized list and resource links below)
1. Medications that are safe in infants are typically safe in Lactation
2. Medications safe in pregnancy does NOT always correlated for safe in Lactation
Preferred medication characteristics
1. Medications with a short half life
2. Medications with poor oral absorption
3. Medications with low lipid solubility and high Protein binding
4. Relative concentration in Breast Milk is less than in maternal blood
5. Low oral absorption by infant
6. Medications that do not interfere with Breast Milk supply
7. Medications that do not alter Breast Milk taste
Take medications just before or after Lactation or before infant's longest sleep time
Ask women of child-bearing age if they are lactating when prescribing medications
Pumping and Dumping is not benign (especially in early Lactation)
1. Even 1-2 days of Lactation interruption can result in stopping Breast Feeding altogether
Patient Education
1. Lactating women should ask physician or pharmacist before new medication

Physiology

Medications diffuse into Breast Milk from serum
1. Active transport of medications (e.g. Cimetidine, Nitrofurantoin) into Breast Milk is uncommon
Medication concentrations in Breast Milk and absorption by the infant depend on several characteristics
1. Serum drug concentration
2. Medication diffusion characteristics (see preferred medication characteristics as above)
3. Older infants have greater function in Drug Metabolism
4. Breast structural changes
  1. Large alveolar cell gaps in the early Postpartum Period allow for easier medication diffusion into Breast Milk

Grading

Safety of Medications in Lactation is assessed by AAP and ACOG in the U.S.
American Academy of Pediatrics (AAP)
1. Compatible with Lactation
2. Use with Caution
3. Incompatible with Lactation
4. Unknown or not evaluated
American College of Obstetricians and Gynecologists (ACOG)
1. L1: Safest
2. L2: Safer
3. L3: Moderately safe
4. L4: Possibly hazardous
5. L5: Contraindicated

Management
Antibiotics considered safe in Lactation

Preferred
Acceptable
1. Macrolides
  1. Erythromycin is concentrated in human milk with increased risk of Pyloric Stenosis)
2. Fluoroquinolones
  1. Considered safe by AAP (but risk of Arthropathy)
  2. Calcium in Breast Milk decreases infant gastrointestinal absorption
3. Aminoglycosides
Use with caution
1. Clindamycin
  1. Diarrhea risk
  2. Hematochezia risk with IV administration in lactating mothers
2. Doxycycline
  1. Appears safe for use up to 21 day duration
  2. Calcium in Breast Milk decreases infant gastrointestinal absorption
3. Metronidazole
  1. Diarrhea risk, candida infection risk
4. Nitrofurantoin
  1. Avoid in infants with G6PD and in the first month of life due to Hemolysis risk
5. Sulfa Antibiotics
  1. Avoid in infants with G6PD and in the first month of life due to Hyperbilirubinemia and Kernicterus risk

Management
Analgesics

Agents considered safe in Lactation
1. Acetaminophen (Tylenol)
2. Ibuprofen (Motrin)
  1. Preferred NSAID
3. Toradol
  1. Probably safe (but Parenteral dosing has not been studied)
4. Topical NSAID (e.g. topical Diclofenac)
5. Local Anesthetics (e.g. Lidocaine)
Agents to use with caution
1. Aspirin (AAP recommends use with caution)
2. Opioids
  1. Risk of infant sedation (use low dose and short duration)
  2. Morphine
  3. Fentanyl
  4. Hydrocodone (Vicodin, <30 mg/day)
Agents to avoid in Lactation
1. Meperidine (Demerol)
  1. Long-acting metabolites with increased infant sedation risk
2. Tramadol
  1. Ultra-rapid metabolizers may expose infants to toxic Opioid doses
3. Hydromorphone (Dilaudid)
  1. Long half life
4. Oxycodone
  1. Concentrates in Breast Milk
  2. CNS Depression seen in 20% of exposed lactating infants
5. Naproxen
  1. Long Half-Life
  2. Case reports of infant adverse effect on LactMed (bleeding, Anemia, Emesis)
6. Other NSAIDs are not recommended due to limited safety data
7. Codeine
  1. Poor Analgesic with variable activity, and generally not recommended as an Analgesic for anyone
  2. Ultra-rapid metabolizers may expose infants to toxic Opioid doses

Management
Procedural Sedation

Agents considered safe in Lactation
Agents with unknown safety in Lactation
1. Ketamine

Management
Anticonvulsants in Lactation

Very low Breast Milk concentrations (highly bound)
1. Phenytoin (Dilantin)
2. Tiagabine (Gabitril)
3. Valproate
Low to moderate Breast Milk concentrations
1. Carbamazepine
2. Phenobarbital
3. Lamotrigine
4. Topiramate (Topamax)
5. Zonegran
6. Primidone (metabolized in part to Phenobarbital)
  1. Risk of infant sedation
  2. AAP recommends using with caution
High Breast Milk concentration (minimally bound)
1. Gabapentin
2. Levetiracetam (Keppra)
3. Ethosuximide (AAP: Compatible with Lactation)

Management
Respiratory

Allergic Rhinitis
1. Preferred medications
  1. Intranasal Corticosteroids (e.g. fluticasone, budesonide)
2. Acceptable medications
  1. Second Generation Antihistamines (e.g. Loratadine)
    1. May decrease milk supply
3. Other medications to use with caution or avoid
  1. First Generation Antihistamines (e.g. Diphenyhydramine)
    1. Risk of infant sedation and decreased milk supply
Upper Respiratory Infection
1. Preferred medications
  1. Nasal Saline
  2. Topical Decongestants (e.g. Oxymetazoline)
2. Other medications to use with caution or avoid
  1. Pseudoephedrine
    1. Risk of decreased milk supply
Asthma
1. No major medication contraindications (most Asthma medications are considered safe in Lactation)
2. Preferred medications
3. Accetable medications
  1. Omalizumab (Xolair)
  2. Systemic Corticosteroids (oral or IV)
    1. Prednisone has very low Breast Milk concentrations without infant adverse effects
    2. High dose or prolonged use may have additional risks
      1. May decrease milk production
      2. Delay Breast Feeding 4 hours after Corticosteroid dose to reduce infant exposure
4. Medications to avoid or use with caution
  1. Theophylline

Management
Cardiovascular Medications in Lactation

Antihypertensives
1. Preferred agents considered safe in Lactation
  1. ACE Inhibitors (avoid in first 6 weeks, risk of renal toxicity in Premature Infants)
    1. Does not significantly pass into Breast Milk
    2. Captopril
    3. Enalapril
    4. No data on Lisinopril (but considered safe as with other ACE Inhibitors)
  2. Hydrochlorothiazide
    1. Theoretically may decrease milk production (not observed)
  3. Angiotensin Receptor Blockers
    1. High Protein binding with minimal passage into Breast Milk (however limited safety data)
    2. Avoid in the Lactation of newborns and Preterm Infants
  4. Methyldopa
2. Other agents to use with caution or avoid
  1. Calcium Channel Blockers
    1. Poorly pass into Breast Milk
  2. Beta Blockers
    1. Typically avoided in Lactation
    2. Beta Blockers are highly variable in their Breast Milk concentrations across the class
    3. Metoprolol and Labetalol appear to be safest (lower Breast Milk concentrations) in this class if needed during Lactation
    4. Avoid Acebutolol
Miscellaneous drugs considered safe in Lactation
1. Digoxin
2. Coumadin
3. Heparin (not excreted into Breast Milk)
Medications to avoid in Lactation
1. Amiodarone

Management
Mental Health Disorders

Antidepressants considered potentially safe in Lactation
1. Antidepressants used during pregnancy are typically continued safely into Lactation period
2. AAP recommends use with caution
  1. Unknown longterm effect
  2. Use if benefits outweigh risk
3. Preferred agents
  1. SSRIs are generally considered safe in pregnancy (but preferred agents have long data record)
  2. Sertraline
  3. Paroxetine
    1. Not used in pregnancy (Teratogenic in first trimester)
4. Other agents to use with caution or avoid
  1. Fluoxetine
    1. Risk of colic, irritability, Sleep Disorders, feeding problems and decreased growth
    2. Long half life
  2. SNRI (e.g. Venlafaxine)
    1. Typically considered compatible with Breastfeeding
    2. However, SSRIs are preferred due to longer data record
Anxiolysis
1. Antidepressants (see above)
2. Benzodiazepines
  1. May be used in Lactation with rare infant sedation
    1. However avoid combining with other agents causing sedation (e.g. Opioids)
  2. Preferred
    1. Lorazepam
  3. Use with caution or avoid
    1. Clonazepam
      1. Higher infant sedation risk
Attention Deficit Disorder
1. Preferred medications
  1. Methylphenidate (Ritalin)
    1. Safest of the ADHD Medications in Lactation
    2. Low levels of Methylphenidate are found in Breast Milk, but not in infant serum
    3. Risk of lower Prolactin levels, and theoretical risk of decreased Lactation effects (but not observed)
2. Accetable medications
  1. Amphetamines (e.g. Dextroamphetamine or Adderall)
    1. Considered acceptable in Lactation
    2. Decreases Serum Prolactin
    3. Higher Breast Milk and infant serum levels
3. Oher ADHD Medications to use with caution or avoid
  1. Clonidine
    1. Diffuses easily into Breast Milk and risk of infant Hypotension
  2. Atomexetine (Strattera)
    1. Limited safety data
Opioid Replacement Therapy
1. Opioid replacement is far safer than relapse of Opioid Abuse
2. Buprenorphine or Methadone
  1. Buprenoprhine has less safety data compared with Methadone
  2. Risk of poor weight gain
  3. Risk of motor delay at 1 year with Methadone
  4. Risk of sedation and respiratory depression
    1. Highest risk with Methadone >100 mg/day or if infant unexposed to Opioids in utero
  5. Opioid Withdrawal
    1. May occur with abrupt Lactation Discontinuation
Cannabinoids and Marijuana
1. Tetrahydrocannabinol is concentrated in Breast Milk and found in infant serum
2. Some Cannabinoids are contaminated with Heavy Metals, pestacides that may be harmful to infants
3. Regular Marijuana use may interfere with parental care of the infant

Management
Diabetes Mellitus

Preferred medications (not found in Breast Milk)
1. Insulin
2. Metformin
3. Second Generation Sulfonylurea (e.g. Glipizide, Glimepiride)
Other agents with unknown effects (Limited safety data, use with caution or avoid)
1. Manufacturers recommend against use in Lactation
  1. However, these drugs are large Proteins unlikely to enter Breast Milk or have infant GI absorption
2. GLP-1 Agonist (e.g. Semaglutide, Liraglutide)
3. SGLT2 Inhibitor (e.g. Empagliflozin, Canagliflozin, Dapagliflozin)

Management
Contraception

Preferred
1. Nonhormonal Contraception (e.g. Copper-T IUD)
  1. However, IUD expulsion is higher risk immediately postpartum
2. Progestin-Only Contraception (e.g. Nexplanon, Mirena IUD, Mini-Pill)
Use with caution
1. Combination Oral Contraceptives (with Estrogen)
  1. May decrease milk production (avoid in first 4-6 weeks postpartum)
  2. Estrogens have no effect on Breast Milk composition or infant growth and development

Management
Imaging Contrast and Radiation

Imaging studies requiring no interruption in Breast Feeding (low infant exposure risk)
1. MRI imaging wih gadolinium
2. CT IV Contrast
  1. Does not require interruption of Breast Feeding (i.e. pump and dump)
  2. Only 1% of IV contrast reaches Breast Milk, and only 1% of that is absorbed by the infant
  3. Newman (2007) Can Fam Physician 53(4): 630–631 [PubMed]
3. Hepatobiliary Iminodiacetic Acid (HIDA Scan)
Many nuclear medicine scans require pumping Breast Milk and storing for set period until radiation has dissipated
1. Example: V/Q requires 13 hour interruption in Breast Feeding (but may pump and store)
Radioactive Chemicals used in Nuclear Medicine
1. Gallium-67 (in Breast Milk up to 14 days)
2. Indium-111 (in Breast Milk up to 20 hours)
3. Iodine 131 (in Breast Milk up to 14 days)
4. Radioactive Sodium (in Breast Milk up to 96 hours)
5. Technetium-99m (in Breast Milk up to 3 days)

Management
Assorted medications considered safe in Lactation

Management
Herbs and Teas

See Herbals
Avoid Caffeine more than 2 beverages per day
FDA does not regulate Herbals
1. Potency, purity and safety is not assured
Galactagogues (reported to increase Breast Milk production with low efficacy, but low toxicity risk)
1. Fenugreek
2. Fennel
3. Milk Thistle
Herbs that may decrease milk production
1. Sage
2. Peppermint
3. Parsley
4. Chasteberry
5. Jasmine
Herbs considered safe in Lactation
1. Chamomile
2. Garlic
3. Ginger
4. Ginseng
5. Valerian
Teas considered safe in Lactation
1. Chicory
2. Orange Spice
3. Raspberry
4. Red bush tea
5. Rose hips
Herbs to avoid due to reported adverse effects in infants
1. Kava
2. Yohimbine

Management
Contraindicated Drugs in Lactation

Medications that decrease milk production
1. Bromocriptine
Chemotherapeutic Medications
1. Cyclophosphamide
2. Cyclosporine
3. Doxorubicin
4. Methotrexate
5. Gold salts
6. Propylthiouracil
7. Methimazole
Cardiovascular medications to avoid in Lactation
1. Avoid Atenolol and use other Beta Blockers only with caution
2. Avoid Acebutolol
3. Avoid Amiodarone
Miscellaneous Medications
1. Dextroamphetamine
2. Ergotamine
3. Lithium
4. Metronidazole (esp. if 2 gram dose)
5. Chloramphenicol
6. Potassium Iodide
7. Phenindione (Anticoagulant)
Drugs of Abuse
1. Amphetamine
2. Cocaine
3. Heroin
4. Marijuana
5. Nicotine
6. Phencyclidine

Resources

LactMed (gold standard professional reference in U.S.)
1. https://toxnet.nlm.nih.gov/newtoxnet/lactmed.htm
InfantRisk
1. https://www.infantrisk.com/
E-Lactancia (spanish and english translations and includes lay language)
1. https://www.e-lactancia.org/
Thomas Hale's Medications and Mother's Milk (Online, Smartphone App, textbook)
1. https://www.halesmeds.com/

References

(2000) Harriet Lane Handbook, Mosby, p. 913
Hale (2006) Medications and Mother's Milk, Hale Publishing
Briggs (1998) Drugs in Pregnancy and Lactation, 5th ed
Mason and Wheaton in Herbert (2018) EM:Rap 18(11): 8-9
Middleton (1998) Allergy, Mosby, p. 941
Sakas and Welsh (2022) Crit Dec Emerg Med 36(3): 9
(1994) Pediatrics 93:137-50 [PubMed]
Howard (2001) Pediatr Clin North Am 48(2):485-504 [PubMed]
Spencer (2022) Am Fam Physician 106(6): 638-44 [PubMed]