Navigating the array of prescription and over the counter (OTC) medications during pregnancy or lactation requires a benefit versus risk analysis for each individual request in order to consider the importance of effective treatment whilst taking care of both maternal and fetal well-being. It is a pharmacist’s responsibility to ensure a safe and informed decision is made for the patient regarding their medication. Nine in ten women consume at least one medication during pregnancy. Research has shown that Australian community pharmacists are “risk averse” and “cautious in offering advice” to pregnant or breastfeeding patients who present in the pharmacy. The same can be assumed for pharmacists in Ireland.

Patients frequently exercise extreme caution when using medications while pregnant as they fear something bad could happen to their growing baby. However, the patient should be reminded that, “the health of the child begins with the health of the mother”. Following a risk-benefit analysis, it is often the case that the risk posed to mother and/or infant, by not treating a maternal condition, outweighs a theoretical risk of adverse fetal or pregnancy outcomes posed by use of a medication. It should be borne in mind that there are only a small number of medications that are absolutely contraindicated for use during pregnancy, including but not limited to warfarin, DOACs, methotrexate, sodium valproate, ACE-inhibitors, ARBs and isotretinoin.

Similarly, the medications that patients take may discourage them from breastfeeding. A study carried out in 2000 discovered that 28.1 per cent (n=124) of mothers were not questioned if they were breastfeeding when purchasing a medication from a pharmacy.  It is imperative to ask whether or not breastfeeding is ongoing as it cannot be assumed that a medicine used in pregnancy will have the same risk during breastfeeding. Pharmacists can encourage the safe and appropriate use of medications while breastfeeding through health promotion and interactions with new parents. The World Health Organization (WHO) recommends exclusive breastfeeding for the first six months of life, with supplemental breastfeeding continuing for two years and beyond. Breastmilk’s nutritional composition specifically meets a baby’s needs for growth and well-being. In order to assist this, pharmacists should ensure that patients take their medications as directed, when breastfeeding concomitantly is deemed safe.

This article provides a comprehensive guide tailored for pharmacists on how they can compile essential information, address patient enquiries effectively and confidently supply medicines, either on foot of a prescription or OTC, to patients who are pregnant or breastfeeding.

The role of the pharmacist

In terms of medication use in this cohort of patients, community pharmacists play the crucial role of being the last professional seen by a patient after medications have been prescribed. In the context of pregnancy and breastfeeding, some of the services that pharmacists provide include choosing the right vitamins and supplements for expecting and nursing mums, counselling on nausea and vomiting, and suggesting solutions for treating different kinds of pregnancy-related pain. Navigating these responsibilities can be demanding, especially under the pressure of a busy pharmacy setting when time is of the essence. The following resources will help you to source the most up to date and accurate information when addressing queries, which can then allow you to devote sufficient time to efficiently counsel and reassure your patients. It is essential to have access to reliable resources that facilitate prompt and informed counseling. These resources not only enable pharmacists to provide confident guidance but also instill a sense of reassurance in patients, especially those who are wary and may have experienced difficulties in conceiving.

Collecting information at the time of the query

1. Identify the medicine and the indication it is being used for;
2. Identify frequency, route and duration of the medicine being taken (if applicable); and
3. Ask how many weeks pregnant the patient is. Finding reliable information requires being trimester specific as there is a lot of data pertaining to the first trimester which would not be of relevance if the patient is in a different trimester.

How to find accurate safety information for medication use during pregnancy and breastfeeding

1. The UK Teratology Information Service (UKTIS), accessible at uktis.org, offers medical professionals scientific data regarding the effects of medications during pregnancy. It offers information from clinical trials and an overview of the medication’s recommended uses. This open access database is extremely practical and should be a community pharmacist’s first port of call;
2. Brigg’s Drugs in Pregnancy and Lactation is an excellent resource book that lists over 1,400 of the most common medicines taken during pregnancy and lactation in an alphabetical manner. The arrangement makes it easy for users to find a monograph. Be cautious as they list drugs using the American generic names. Paracetamol, for instance, will be under acetaminophen. Although the book can be purchased in paperback or online, updates are only made accessible online. The book can be accessed online through a subscription to the MedicinesComplete Compendium;
3. British National Formulary for Drugs in Pregnancy and Lactation is another well-known resource. It is easy to glance through as it contains subsections for fetal risk summary and breastfeeding summary. It will indicate whether a medication poses a low or high risk to a developing fetus;
4. Reprotox is a database containing summaries on the effects of drugs, chemicals, biologics, and physical agents on lactation and pregnancy that may be accessed at reprotox.org. The material is updated frequently, and it reads quickly and thoroughly. A membership is required, although it is available to students and those in training without charge. This resource offers quite in-depth analysis of most recent studies and surveillance relating to safety of medication use in this patient cohort;
5. MotherSafe is a free comprehensive counselling service that produces factsheets that are available on the website of the South Eastern Sydney Local Health District (available at seslhd.health.nsw.gov.au > MotherSafe > MotherSafe factsheets). These factsheets provide advice on how to handle ailments like constipation and heartburn that arise during pregnancy and lactation. The factsheets can be easily printed for use;
6. Best Use of Medicines in Pregnancy (BUMPS), found on medicinesinpregnancy.org provides free evidence-based and accurate information about the use of medicines in pregnancy. You can search for medicines using an A-Z index or by category, such as vaccinations or colds and flu;
7. Martindale: The Complete Drug Reference and Micromedex are useful as they provide clear and precise information from their pregnancy and lactation section in each drug’s monograph. Martindale can be accessed through Medicines Complete;
8. Searching the literature can be beneficial when combined with a precise search technique. Embase, PubMed and Medline can be used; and
9. The Summary of Product Characteristics (SmPC) provided by the pharmaceutical company which takes a very conservative medico-legal approach. It frequently contraindicates drug use in pregnancy. Women who are pregnant or nursing are often excluded from clinical research trials for ethical reasons, therefore a SmPc will often state “in view of lack of clinical data, use in pregnant women is not recommended”, in order to protect themselves from potential legal action. While the information contained within the product’s SPC should be considered from a medico-legal viewpoint, it is imperative for the health and wellbeing of both mother and fetus that the manufacturer’s recommendations are considered in the context of the information contained within the reference sources listed above. In cases where published literature is frequently absent, the manufacturer’s Medicines Information Department may be able to provide information for new pharmaceuticals on the market.

The following are for breastfeeding only:

10. LactMed® is a comprehensive and open access drugs and lactation database which can be found on the National Center for Biotechnology Information (NCBI);
11. e-lactancia is a free database which can be used to determine whether medications and alternative products are compatible with breastfeeding. It offers a brief overview and assigns a risk level ranging from very low to very high. If there is a danger associated, e-lactancia offers safe and breastfeeding-compatible alternatives which is extremely helpful when contacting a prescriber to make a recommendation;
12. The Breastfeeding Network (BfN) is a great source of information for breastfeeding women and provides a Drugs in Breastmilk service led by pharmacist Dr. Wendy Jones MBE. This service includes a series of factsheets about different medication accessible through the BfN website (breastfeedingnetwork.org.uk/drugs-factsheets). The factsheets are valuable as a quick and easy to use source of information available in a PDF format for easy printing; and
13. The Specialist Pharmacy Service (SPS) website has an excellent article titled Questions to ask when giving advice on medicines and breastfeeding (available at sps.nhs.uk > Guidance > Safety in breastfeeding). SPS is commissioned by the NHS and has resources published by a team of pharmacy professionals. The article is part of a series that will guide you on how to gather information and includes information sources on medicines in breastfeeding too.

Key points

1. Recommend using the lowest effective dose for the shortest required duration;
2. During first 12 weeks of gestation, it is best to minimise use of non-essential medications as this period is very important for the development of the fetus; and
3. Medications that have been used extensively and have a good safety record should be preferred. It is important to keep in mind that a lack of evidence of fetal harm or adverse pregnancy outcomes does not necessarily indicate that a medication is safe to use.

How to contact The National Maternity Hospital?

The pharmacy department at The National Maternity Hospital offers a medicines information service for healthcare professionals and patients.  If you have consulted the above reference sources and are still unsure and looking for support, you can contact the pharmacy team in the National Maternity Hospital by email at pharmacy@nmh.ie or call at 01 637 3485.

Conclusion

Pharmacists play a vital role in supporting appropriate medication use in women during their journey through pregnancy and into the postnatal period. Using the above-mentioned references, pharmacists can inform themselves about the safety of commonly used drugs during pregnancy and lactation. It is advised to consult several references in order to create a comprehensive response to a query, as opposed to relying solely on one source.

References are available upon request.