Thank you for the opportunity to speak today. My name is Dr. Laura Gottschalk and I’m speaking today on behalf of the National Center for Health Research. Our research center scrutinizes scientific and medical data and provides objective health information to patients, providers, and policy makers. We do not accept funding from pharmaceutical companies, therefore I have no monetary conflicts of interest. However, I am currently 8 months into breastfeeding my second child, so I do have a personal interest in all of the issues being discussed at this workshop.
As a lactating mom, it can be frustrating trying to figure out what medicines I can and can’t take while breastfeeding. However, I realize that I am lucky because none of the medications that I take are absolutely necessary. Yet, many mothers, such as those on antidepressants or in need of chronic pain management, don’t get the luxury of just going without. Therefore, we are pleased that the FDA has organized this meeting to discuss the current challenges in studying drugs in lactating women. We realize that one of the hurdles faced in lactation studies is simply trying to find lactating patients who are willing to participate. However, while trying to recruit patients, we would like to encourage the inclusion of women of diverse races, ethnicities, and age when possible.
Historically, clinical trials have been performed on young, white men. Clearly, sex isn’t issue with lactation studies. However age, race, and ethnicity can all play a large role in how drugs are metabolized, and as a result, transmitted to the breast milk. A classic example is the case of the infant who died as a result of the mother’s codeine use. Normally, codeine has been considered safe for use in breastfeeding mothers and is frequently prescribed to women after cesarean section births. However, this particular mother happened to have a genotype that classified her as an “ultra-rapid metabolizer” of codeine. This resulted in her body quickly metabolizing codeine into a large bolus of its active form, morphine, which was passed on to her infant through her breast milk, ultimately resulting in the death of the baby.
The frequency of the “ultra-rapid metabolizer” genotype varies between populations. Per the FDA website, about 1-10% of Caucasians are classified as “ultra-rapid metabolizers.” However, among North Africans, Ethiopians, and Saudi Arabians, 16-28% of the population is considered an “ultra-rapid metabolizer.” This is just one example of how characteristics of a racial or ethnic group can contribute to the drug response of a patient. Additionally, it is well documented that age of a patient can change the pharmacokinetics and pharmacodynamics of drugs. Although no lactating woman would be considered “elderly,” there is the possibility of a difference in metabolism between a 16 year old mother compared to a 40 year old mother.
As has been discussed here, more clinical studies are desperately needed to determine the safety of drugs in lactating mothers. When these studies are in the planning stages, be cognizant of enrolling mothers that represent a wide diversity of races, ethnicities, and–when appropriate for the drug–ages. We need safety information for ALL mothers and their breastfeeding infants. Thank you.