All drugs transfer into milk. The extent is less than drug transfer during pregnancy.
General Advice
- Consider non-drug measures first; avoid all drug therapy if possible, as the infant does not usually benefit from drug exposure via breast milk.
- The infant risk depends on the dose ingested via milk, the oral availability, and the clearance in the infant.
- Monitor the infant for adverse effects of the drug (e.g. failure to thrive, sedation, diarrhoea).
- Dose after a feed where possible, to minimise drug exposure. Concentrations in the milk follow concentrations in maternal plasma.
- Drug therapy rarely constitutes a reason to avoid breastfeeding. Consult readily with specialists in the area (e.g. Medicines Information).
| Table 1: Drugs considered ‘Safe’ 1 when Breastfeeding Full-term Healthy Babies 2 | |
| 1. An infant dose <10% of the maternal dose on a mg/kg basis – Weight Adjusted Maternal Dose (WAMD) for drugs that do not have a low therapeutic index.
2. This table is a guide only and the list is not exhaustive. Consult when the infant is premature, has significant renal or hepatic disease or G6PD deficiency, or when the maternal dose is unusually high or poorly controlled (e.g. social drugs). |
|
| Class | Examples of Individual Drugs |
| Analgesics | opioid analgesics* (short courses – < 2 days): morphine, oxycodone, codeine, paracetamol |
| Anticoagulants | enoxaparin, heparin, warfarin (monitor infant INR) |
| Anticonvulsants* | carbamazepine, phenytoin, valproate sodium |
| Antidepressants* | SSRIs: citalopram, escitalopram, paroxetine, sertraline
SNRIs: venlafaxine tricyclics: amitriptyline, nortriptyline |
| Antidiabetic | insulin, metformin |
| Antihistamines | cetirizine, loratadine |
| Antihypertensives | ACE inhibitors: enalapril, quinapril
beta blockers: labetalol, metoprolol, propanolol calcium channel blockers: diltiazem, nifedipine methyldopa |
| Antimicrobials | betalactams: amoxicillin, flucloxacillin
cephalosporins: cefalexin, ceftriaxone, cefazolin, cefuroxime, cefotaxime, cefepime, ceftazidime macrolides: azithromycin, clarithromycin, erythromycin, roxithromycin metronidazole (shorter courses – e.g. 400 to 600 mg BD for 7 to 10 days; avoid higher doses e.g. 2000 mg) nitrofurantoin trimethoprim, trimethoprim/sulfamethoxazole |
| Antipsychotics* | haloperidol, olanzapine, quetiapine, risperidone |
| Antivirals | aciclovir, valaciclovir |
| Benzodiazepines* | Short courses ( < 2 days) of midazolam, temazepam, zopiclone |
| Cardiac | digoxin |
| Contraceptives | progestogen-only, combined oral contraceptives after 6 weeks post-partum |
| Corticosteroids (short courses) | prednisone (<20 mg/day) |
| Gastrointestinal drugs | domperidone
proton pump inhibitors: omeprazole, pantoprazole mesalazine ranitidine |
| NSAIDs | diclofenac, ibuprofen |
* For all, monitor infant for adverse effects (e.g. sedation, jitteriness, lethargy, poor feeding).
| Table 2: Drugs Considered ‘Unsafe’ During Breastfeeding
Consult Medicines Information ( 80900). May require individual decisions. |
| amiodarone |
| antineoplastic drugs |
| ergotamine |
| immunosuppressants (some) |
| iodine-containing agents |
| lithium (requires infant drug concentration monitoring) |
| retinoids (e.g. isotretinoin) |
| social drugs (e.g. alcohol, cannabis), opioids (long courses > 2 days) |