Prescribing for the pregnant patient
ABSTRACTPrescribing in pregnancy can be challenging for providers facing insufficient information about drug safety, overestimation of the risk of medications by both the patient and the care provider, and increasing litigation costs. This article provides key concepts to consider when prescribing for a pregnant patient and offers practical advice for choosing the safest possible drug treatments.
KEY POINTS
- There is no protective physiologic barrier between the maternal and fetal environments.
- The gestational stage may determine the effect of a medication on the fetus.
- The physiologic changes of pregnancy affect the pharmacokinetics of medications.
- Sole reliance on the US Food and Drug Administration’s pregnancy safety category may be inadequate.
- Key questions: Is the problem self-limited or amenable to nonpharmacologic management? How do the patient’s (and provider’s) presumptions affect decisions about this medication in pregnancy? How does pregnancy affect the problem, and how does the problem affect pregnancy?
How do the patient’s (and your) values and understanding affect the decision?
Is the patient willing to take medication? What are her beliefs with regard to her problem and how it should be managed in pregnancy?
Women and clinicians bring many worries and prejudices to the use of medications in pregnancy. The experiences of the patient and her family and friends may present huge obstacles to needed medication use in pregnancy. Misinformation in the media and from family members, friends, and other health care providers are other obstacles. The only way to deal with this issue is to ask your patient directly about her fears and concerns regarding each prescription written.
Clinicians also need to address fears or prejudices they themselves may have about medication safety in pregnancy. These may arise from a single bad experience in caring for a pregnant woman, discomfort with uncertainty, or a belief that pregnant women should avoid any and all risks of exposures, even when the mother’s condition warrants pharmacologic treatment.
Being informed, both scientifically and about one’s own biases or tendencies, is an essential foundation for rational prescribing in pregnancy.
Is the problem affected by pregnancy, and how?
Pregnancy can affect many medical conditions, and in different ways. Conditions such as asthma, migraine headache, and cardiac arrhythmia are exacerbated in pregnancy, placing the mother and fetus at increased risk of morbidity. Conditions such as Graves disease and hypertension may improve as pregnancy progresses, and medications often can be withdrawn as the patient progresses further along in gestation.
Understanding the effect of pregnancy on a particular problem may help the clinician to make an informed decision about medication use in pregnancy.
How does the problem affect pregnancy?
Considering the risk of untreated disease to the pregnancy may help in decision-making.
Many medical conditions can negatively affect the development of the fetus. A glaring example is diabetes mellitus, with poor glycemic control being linked to congenital malformations, spontaneous abortion, and fetal demise. Chronic conditions with periodic exacerbations such as asthma or epilepsy place the fetus at increased risk during a flare-up.
Therefore, for chronic conditions, continuing maintenance therapy is best. Preconception counseling in such cases is crucial, so that a drug with adequate safety data can be substituted before pregnancy. In this way, any risk to the mother or the embryo from exacerbation of disease as such adjustments are made is avoided.
For conditions arising de novo in pregnancy, the underlying principle remains the same. Is the risk of pharmacotherapy more than the risk of untreated disease? Invariably, the answer to this question supports medication use, and an educated provider will be able to choose a treatment that is justifiable in most circumstances.
CHOOSING A MEDICATION
Fetal well-being depends on maternal well-being. It therefore helps to think of medication use in pregnancy as “justified or not” rather than “safe or not.” Table 3 lists some conditions commonly seen in pregnancy, selected drugs of choice that can be safely used for treating those conditions, and alternates that may be justified in some circumstances.5,6,14–18
GOOD PRACTICES WHEN PRESCRIBING IN PREGNANCY
Prescribing in pregnancy will be most successful when both the patient and the prescribing physician consider the fetal benefit gained from optimizing maternal health. Good prescribing practices to ensure optimum therapeutic benefit when caring for a pregnant patient are to:
- Involve the patient in decision-making. Recognize her concerns, worries, and preferences regarding her illness and its treatment.
- Inform the patient of the risk of an untreated medical condition, weighed against the risk of medication.
- Choose medications with the most available safety data. Let the patient know what resources you have referred to in choosing the medication.
- It is advisable to perform a search each time a prescription is written for a pregnant or lactating woman.
- When possible, have the discussion in the preconception period.
- Consider the dynamic physiology of gestation. Choose the right drug for the right trimester.
- Discuss the plan with the patient and other providers.
- Define clear criteria for when to discontinue the treatment.
