(LifeWire) - In an ideal world, pregnant women would avoid all medication. That philosophy is not only unrealistic, but it is potentially risky for some expectant women whose acute or chronic illness requires ongoing treatment.
Fortunately, only a handful of common medications should be avoided during pregnancy, and only one over-the-counter (OTC) drug should be avoided at any stage of pregnancy, and that is aspirin -- unless specifically prescribed by your doctor. Because of its blood-thinning properties, aspirin can cause bleeding problems in the fetus, as well as heavy bleeding during childbirth.
Whether to treat headaches and colds or more serious conditions, such as infections, asthma or diabetes, many pregnant women avail themselves to using OTC or prescription drugs. The American Academy of Family Physicians reports a study that indicated more than 92% of women self-treat with OTC drugs while pregnant. Another survey revealed that 46% of women in their childbearing years of 18 to 44 took prescription medicine in the previous week, potentially impacting an undiscovered pregnancy, according to the United States Centers for Disease Control and Prevention.
Experts don't know how many birth defects are caused by prescription drugs. Obtaining complete information is limited by the ethical considerations of testing drugs on pregnant women. Some are tested on pregnant animals instead. Nonetheless, the FDA requires all drug labels to list the known risks to pregnant women or those who are trying to conceive.
Pregnancy drug labeling splits medications into five categories: A, B, C, D and X.
Group A includes the thyroid drug levothyroxine, which shows no recorded problems for babies in human studies.
Group B includes the pain reliever Tylenol (acetaminophen), antibiotics such as amoxicillin, the nausea drug Zofran (ondansetron) and some insulins for diabetes, which show no evidence of risk in humans. (While animal studies either showed no risk or small risk, human studies showed none.) Examples of problems related to Group B drugs include a very small increased risk of complications, such as pre-eclampsia or stillbirth. These drugs are still considered safe during pregnancy.Group C includes the yeast infection drug Diflucan (fluconazole), Ventolin (albuterol) for asthma, and the drugs Zoloft (sertraline) and Prozac (fluoxetine) for depression. Risks from Group C drugs cannot be ruled out, based on no available human studies and scant or negative studies on animals. Problems associated with this class of medications include slightly smaller birth weights and possible withdrawal symptoms in the baby after birth. However, the benefits of the drug to mother and infant may outweigh the risks.
Group D includes Eskalith or Lithobid (lithium) for bipolar disorder, the epilepsy drug Dilantin (phenytoin), and some cancer chemotherapies that show some problems for babies in human studies, including heart defects and other malformations. But again, the benefits may outweigh the risks.
Group X includes the cystic acne drugs: Accutane (isotretinoin) and Thalomid (thalidomide) for multiple myeloma and other conditions, which shows major risks to babies. Accutane, for instance, can cause heart defects, mental retardation, or abnormal head and brain size in infants, whereas thalidomide is associated with severe malformations, such as missing limbs. These prescription drugs should not be taken during pregnancy
Women planning to become pregnant -- especially those with chronic health conditions -- should review their medication needs with their doctors and switch to safer drugs if possible.
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