Nausea is the most common gastrointestinal symptom experienced during pregnancy.
NAUSEA AND VOMITING
Although the cause of nausea and vomiting during pregnancy is not known, the increase in the hormone human chorionic gonadotrophin is believed to be involved. Nausea is the most common gastrointestinal symptom experienced during pregnancy. Nausea and vomiting are estimated to occur in about 80% to 85% of all pregnancies during the first trimester. In 15% of women, nausea and vomiting may continue throughout the entire pregnancy. It is important to note that vomiting is rarely present without nausea.1,2
The use of acupressure and acustimulation for managing nausea and vomiting during pregnancy has produced mixed results. Therefore, these treatments are recommended for mild or moderate cases.2
Inform women that most cases of nausea and vomiting resolve on their own during weeks 16 to 20 of gestation. If nausea or vomiting is severe and does not respond to nonpharmacologic measures, the use of antihistamines may be considered.1,2 If OTC treatment options are ineffective, ondansetron may be prescribed.
Note that further research is required to evaluate the safety of all nausea and vomiting interventions, except antihistamines.1
Heartburn is another common symptom during pregnancy. In one large study that evaluated 607 pregnant women, 22% of the women reported having heartburn in the first trimester, 39% reported having it in the second trimester, and 72% reported having it in the third trimester.1
Mild and infrequent heartburn can be managed by lifestyle and dietary modifications. If these changes are ineffective in managing heartburn and it remains problematic, antacids, such as those containing calcium and magnesium, can be given. These antacids are Pregnancy Category B. It is important that patients not exceed the recommended daily dose.
It is important to consider a woman’s daily intake of calcium during pregnancy, especially if a calcium-containing antacid is added to her regimen. Pregnant women should take 1000 to 1300 mg of calcium per day.2
Women who experience frequent and moderate heartburn should see their health care provider for supervised management.2 Histamine2 (H2) blockers, such as Tagamet (cimetidine), Pepcid (famotidine), Zantac (ranitidine), and Axid (nizatidine), are classified as Pregnancy Category B and have been used during pregnancy. However, women should seek care from their health care provider instead of trying to self-treat their heartburn with H2 blockers. The proton pump inhibitor Prilosec (omeprazole) is classified as Pregnancy Category C and, therefore, should be taken only under a physician’s supervision.2
Constipation is commonly reported during gestation, affecting approximately 1 in 3 pregnant women.1,2 Constipation is thought to be caused by several factors, such as a growing uterus pushing on the colon, a reduction in intestinal muscle tone, and an increase in the progesterone level, all of which affect gastric motility and gastric transit time.1,2 The use of prenatal supplements containing iron and calcium may also be a contributing factor.2
The primary goal in treating constipation during pregnancy is to soften stools without using laxatives.2
Nonpharmacologic1,2 (Table 32)
Patients should increase their fiber intake and include prunes and/or prune juice into their diet. Bulk-forming laxatives are considered the first-line treatment in managing constipation during pregnancy, as this drug class is deemed safe and effective. With the use of these products, women should consume at least 1500 mL of fluids every day or at least 8 oz of fluid with each dose. If bulk-forming laxatives are not effective or are not tolerated well, other treatment options include emollient, senna, or bisacodyl. Medications that should not be used during pregnancy include saline cathartics.2
Hemorrhoids are more common in the last trimester of pregnancy. The results of one study showed that 8% of pregnant women experience hemorrhoids in the last trimester.1
Nonpharmacologic measures should be initiated to manage hemorrhoids. The intake of fiber and fluids should be increased. Sitz baths can be incorporated into the management plan.2 Review the patient’s supplements to ensure that calcium and iron do not exceed the recommended daily doses.2 Patients should be instructed to clean the anorectal area after each bowel movement. Patients should use a moistened, unscented, white toilet tissue or wipe.2
If medication is warranted, protectants are a good option because they are minimally absorbed. Protectants, except glycerin, can be used during pregnancy to temporarily relieve hemorrhoids that are causing discomfort, itching, irritation, and burning. If other agents are used, only products for external use are recommended.2
Dr. Garza received her doctor of pharmacy degree from the University of Texas at Austin. She is currently working as the director of the Life Sciences Library at RxWiki, where she continues to build her practice on the fundamental belief that providing patients with medication information and medical knowledge contributes significantly to the quality of care they receive, and improves quality of life and health outcomes. Her work focuses on educating patients and providing them with the resources needed to navigate the overwhelming and complex health system. Before RxWiki, she was director of pharmacy for a Central Texas Department of Aging and Disability facility.