The safety of drugs to treat IBD during lactation
This article highlights the dilemma facing prescribers when making
decisions about the safety of medications in mothers milk despite
recognition of the beneficial role of breastfeeding in reducing the risk
of IBD in later life.
It underlines the recommendation in the NICE Maternal and Child
Nutrition Guidelines 2008 (1) of the need to look at additional sources of
information NICE to determine the risk of any drug to be given to a
breastfeeding mother. To recommend interruption or cessation of
breastfeeding may have deleterious effects on the long- term health of
mother and child, particularly those with a family history of IBS.
Following this recommendation would have yielded further information
about the drugs listed below:
loperamide, metronidazole, Anti-tumour necrosis factor ,
Fluoroquinolones and azathioprine.
This would allow for the possibility of a fully informed consultation
with the mother and to prescribe appropriately allowing better control of
IBS and continued benefit of breastfeeding for mother and baby. Instead
only 44% of mothers in the study, breastfed their babies and some put
their own health at risk by stopping medication unnecessarily.
Hodinott et al (2) provided an excellent review of the benefits of
breastfeeding recently and it is important that this is borne in mind when
considering the treatment of lactating mothers with chronic or acute
In addition, in light of new FDA recommendations (3), the
pharmaceutical drug companies should be strongly encouraged to license
their products during lactation or provide information to facilitate
evidence based, qualitative prescribing.
The voluntary helpline and website run by BfN (4) on the safety of
drugs in breastmilk has many contacts each year from mothers who wish to
breastfeed but have been told that this is incompatible with their
medication – something which is rarely true.
With the prevalence of breastfeeding at 6-8 weeks a PSA indicator (5)
clinicians need to help by referring to specialist sources of information
on the safety of drugs in breastmilk rather than risk losing the long term
benefits of breastfeeding or the health of the mother who chooses to
breastfeed rather than take her medication.
1. Loperamide - the BNF app 5 (6) notes that the amount of loperamide
secreted into breastmilk is too small to be harmful. Hale in "Medications
and Mothers Milk 2006" (7) estimates a theoretical infant dose of
0.04ìg/kg/day and a relative infant dose of 0.03% well below the safe
limit of 10%.
2. Metronidazole given in divided doses of 200-400mg three times
daily is considered safe and is used frequently in obstetric infections
3. Azathioprine - a study published in 2006(8) was unable to detect 6
-thioguanine and 6-methylmercaptopurine nucleotides (6-TGN and 6-MMPN,
respectively) detected in any of 4 infants studied during maternal use of
azathioprine in breastfeeding and suggest that azathioprine is safe to be
used during breastfeeding. Similarly Moretti et al (9) studied 4 babies
and measured levels of 6-mercaptopurine in breastmilk and neonatal blood
for drug levels, white cell and platelet counts. Levels of metabolites
were below the level of detection in the neonates and no clinical signs of
immunosuppression were observed. Sau et al (10) studied 10 women and
similarly found no immunosuppression
4. Anti-tumour necrosis factor (infliximab) is poorly bioavailable so
levels are likely to be low (7).
5. Fluoroquinolones (e.g. ciprofloaxacin) are known to produce
juvenile arthropathy in rats exposed to the drug directly but this has not
been reported in babies who have been exposed to the drug short-term
through their mother's breastmilk (7).
1. NICE Maternal and Child Nutrition Guidelines 2008 PH11
2. Hoddinott, Tappin, and Wright. Breast feeding. BMJ 2008;336:881,
3. FDA Proposes New Rule to Provide Updated Information on the Use of
Prescription Drugs and Biological Products during Pregnancy and Breast-
feeding. May 28 2008 .
6. British National Formulary (BNF). Pharmaceutical Press (London)
7. Hale T Medications and Mothers Milk (Ed 12 ) 2006. PharmSoft
8. Gardiner SJ, Gearry RB, Roberts RL, Zhang M,Barclay ML, Begg EJ.
Exposure to thiopurine drugs through breast milk is low based on
metabolite concentrations in mother-infant pairs. Br J of Clin Pharmacol.
9. Moretti ME, Verjee Z, Ito S, Koren G. Breast-feeding during maternal
use of azathioprine. Ann Pharmacother. 2006;40:2269-72
10. Sau A, Clarke S, Bass J, Kaiser A, Marinaki A, Nelson-Piercy C
Azathioprine and breastfeeding-is it safe? BJOG 2007336:881,
Pharmacist The Breastfeeding Network Drugs in Breastmilk helpline run on a voluntary basis.Specialist interest in the safety of drugs in breastmilk
Competing interests: No competing interests