US Pharm. 2006;31(9):50-71.

Pregnant women represent a challenging population to treat with both OTC and prescription medications. Well-designed, prospective studies are seldom conducted in pregnant women, and the safety and efficacy of drug therapy is often unclear (Table 1). Therefore, health care practitioners have only modest guidance on what medications are safe for use in pregnant women. Pharmacists face this dilemma on a daily basis with regard to OTC medications during pregnancy. Herein, the appropriate treatment of six gastrointestinal (GI)disorders that occur during pregnancy will be reviewed.

Nausea and Vomiting
Nausea and vomiting of pregnancy (NVP) most commonly affects women in their first trimester. The frequency of NVP may be variable as up to 85% and 50% of pregnant women experience nausea and vomiting, respectively.1 Although often referred to as morning sickness, NVP can occur at any time during the day. The etiology of NVP is unknown and controversial. Psychological factors, GI tract dysfunction, and hormonal changes have been studied as possible causes, but the data are inconclusive. Another study has shown that chronic Helicobacter pylori infection was significantly more prevalent in pregnant women suffering from NVP, compared to pregnant women not suffering from NVP.2


Nonpharmacologic Treatment
Pharmacists should not recommend pharmacologic treatment for NVP. For mild cases of NVP, nonpharmacologic methods to prevent nausea (Table 2) can be recommended. However, pregnant women should always be referred to their physician if such measures are ineffective or if NVP symptoms are more severe. Several serious conditions can initially present with moderate to severe nausea and vomiting. These conditions range from preeclampsia to liver disorders. If a pregnant patient presents with moderate to severe nausea and vomiting, she should be referred to her physician for further evaluation.

It is important to assess the appropriateness of physician recommendations. For nonpharmacologic therapy, physicians may recommend acupressure. There are conflicting data on the effectiveness of acupressure bands. However, these devices appear to be safe.


Pharmacologic Treatment
The American College of Obstetrics and Gynecology (ACOG) issued recommendations for the treatment of nausea and vomiting in pregnancy in 2004.3 One recommendation is for a woman to take a multivitamin while she is trying to conceive. It has been noted in clinical trials that there may be a lower incidence of vomiting if women take a multivitamin at the time of conception. 3 Physicians may suggest many drug therapy options to treat NVP, including pyridoxine, antiemetics, antihistamines, corticosteroids, antimotility agents, and anticholinergics. In general, drug therapy is typically reserved for severe cases of NVP after balancing risk versus benefit.

Ginger, on the other hand, has been shown to decrease nausea and vomiting in cases of hyperemesis gravidarum, and there are no reports of fetal abnormalities.4,5 Ginger contains gingerols and shogaols that may directly affect the digestive tract to prevent nausea and vomiting. Yet, the use of ginger remains controversial. Some warn against the use of ginger because of possible antiplatelet effects. Ginger contains thromboxane synthetase inhibitor. This inhibitor may interfere with testosterone receptor binding in the fetus.6 However, ginger is used as a spice in other cultures in amounts similar to those used to treat NVP, and there are no reports of harm caused with these doses.7 Ginger is available in many forms (e.g., ginger ale, ginger root, and tablets). Administration of 1 g/day in divided doses before meals and at bedtime has been used to prevent nausea.

Emetrol: Emetrol, a combination of dextrose, levulose, and phosphoric acid, is used off-label for treating NVP. This combination of ingredients may act directly on the GI tract to decrease smooth muscle contraction, thus delaying gastric emptying. The pregnancy category for Emetrol is unknown. Table 1 lists pregnancy categories for all medications discussed in this article.

Pyridoxine: Pyridoxine (vitamin B6), either alone or combined with doxylamine, has been used to prevent nausea and vomiting. ACOG recommends pyridoxine as the first step in a pharmacologic treatment plan, due to available safety and efficacy data. Pyridoxine is pregnancy category A if used at doses comparable to the recommended daily allowance (RDA) of 2.2 mg. In fact, many pregnant women may be vitamin B6 deficient, since the demand for this vitamin increases during pregnancy. Exceeding the RDA is not recommended, because the pregnancy category falls to a C level at such doses. The recommended dose of pyridoxine as a treatment for nausea and vomiting ranges from 10 to 25 mg three to four times daily. The prenatal vitamin PremesisRx contains 75 mg of pyridoxine. While this combination makes theoretical sense, this product has not been proved to reduce NVP.3

Pyridoxine was once combined with doxylamine in a product known as Bendectin, which was withdrawn from the market in 1983 due to possible birth defects. However, evidence indicates that this combination may not be teratogenic. Furthermore, doxylamine is pregnancy category B. In 1983, the FDA regarded three studies as the most conclusive regarding the teratogenicity of Bendectin but concluded that there was no definite causal relationship, since nausea and vomiting could increase the risk of teratogenicity. It was not possible to determine if use of Bendectin was completely devoid of fetal risk. Bendectin was thus withdrawn from the market to avoid possible litigation. Pyridoxine-doxylamine (Diclectin) is available in Canada and is still recommended by U.S. physicians. The standard dose of doxylamine is 12.5 mg three to four times daily. Doxylamine is recommended for use in combination with pyridoxine for patients in whom pyridoxine monotherapy was not effective.3

Anticholinergic Medications: Women may also be advised to take antihistamines or anticholinergics such as meclizine, dimenhydrinate, and diphenhydramine. These medications are used to treat NVP, due to their effectiveness. All three are rated pregnancy category B and have not been associated with an increased risk of malformations.3 Common doses are diphenhydramine 25 to 50 mg every four to six hours as needed or dimenhydrinate 50 to 100 mg every four to six hours as needed.

In summary, no OTC medications are FDA approved for the treatment of NVP. For women considering becoming pregnant, a multivitamin should be recommended. If a pregnant patient is experiencing nausea and/or vomiting, nonpharmacologic treatment can be suggested as initial therapy. However, if this fails to control symptoms, or if a woman has moderate to severe nausea and vomiting, she should be referred to her physician for further evaluation. If an OTC medication is recommended, it should be used in conjunction with nonpharmacologic measures. Pharmacists should counsel patients to take the medication on an "as-needed" basis, rehydrate if necessary, and follow up with their physicians if nausea and/or vomiting worsens.


Heartburn or gastroesophageal reflux disease (GERD) is common during pregnancy and is reported by about 30% to 50% of pregnant women; the incidence may be as high as 80% in certain populations.8-10 Although the exact mechanism is unclear, reduced lower esophageal sphincter (LES) pressure has a role in the pathogenesis of GERD in pregnancy. During early pregnancy, the LES pressure responses to hormonal, pharmacologic, and physiologic stimulation are reduced. 11 The resting LES pressure falls about 33% to 50% of baseline, probably due to increased progesterone levels.8 Abnormal gastric emptying or delayed small bowel transit may also contribute to the pathogenesis, but the impact of increased abdominal pressure due to an enlarging uterus is controversial.8

GERD symptoms during pregnancy are similar to those in the general population.8,12 Heartburn is the predominant symptom, but regurgitation also occurs frequently.8 Symptoms can occur at any time during pregnancy but are generally worse during the last trimester.9,13 Dietary triggers that worsen symptoms include fatty foods, spicy foods, and caffeine. Since GERD during pregnancy usually has a short duration and resolves after delivery, complications (e.g., esophagitis and stricture) are rare.8

Nonpharmacologic Treatment
The preferred and safest initial treatment for GERD during pregnancy is lifestyle modification. Such measures include avoiding foods that trigger symptoms (e.g., spicy or fatty food) and elevating the head of the bed (see Table 3). Chewing gum may also help because it stimulates salivary glands, which can help neutralize acid.8 Lifestyle modifications may control mild symptoms in women, but drug therapy may be necessary if symptoms are not relieved by these measures (Table 4).

The FDA has not determined the pregnancy category for antacids, and there are few data on the effects of antacids on the fetus. In animal studies, magnesium-, aluminum-, or calcium-based antacids were not teratotogenic.14 One retrospective case-controlled study reported a significant increase in congenital malformations in infants with third trimester antacid exposure. However, analysis of individual antacids found no link to congenital anomalies.15 Antacid use has not been shown to be unsafe, but there have been no controlled studies.16


Despite the limited data, experts have agreed that antacids should be the first OTC treatment for heartburn during pregnancy.12 Antacids provide fast and effective relief, and up to half of women will require only antacids to control GERD.8 Magnesium-, calcium-, and aluminum-containing antacids at recommended doses are considered safe to use during pregnancy, although some experts preferentially recommend calcium/magnesium-containing antacids, because high doses of aluminum-containing antacids may increase aluminum levels in women and cause fetal harm.8,12,17

Alginates are generally as effective as antacids in controlling GERD symptoms.18 A formulation of Gaviscon that has a lower sodium content was studied in an open-label study in 150 pregnant women.19 Although effective in relieving heartburn, adverse events were reported in 10 fetuses.19 Furthermore, magnesium trisilicate (found in some Gaviscon preparations) may cause fetal nephrolithiasis, hypotonia, respiratory distress, and cardiovascular impairment if used long-term and at high doses.19


In summary, calcium- or magnesium-containing antacids are preferred during pregnancy. Usual dosage of antacids on an as-needed basis should be recommended. Calcium-based antacids provide an additional source of calcium during pregnancy, which may help prevent hypertension and preeclampsia.12 Patients should be counseled on potential interactions of antacids with other drugs and supplements such as iron.

Histamine-2 Receptor Antagonists (H2RAs)
All H2 RAs are FDA pregnancy category B. Cimetidine and ranitidine have been used safely during pregnancy over the last 30 years.8 Only ranitidine, however, has been specifically evaluated in heartburn during pregnancy. Both studies, albeit small and short in duration, showed improvement in heartburn symptoms with ranitidine and no adverse pregnancy outcomes.9,19 There are no prospective randomized studies on the safety of cimetidine and other H2RAs during pregnancy, but the general consensus is that cimetidine and possibly famotidine are safe.8,12 Cohort studies have shown similar pregnancy outcomes and rates of malformation in women exposed to H2RAs during the first trimester, compared to controls. 20,21 Although one animal study suggested antiandrogenic effects of cimetidine and feminization of male offspring, data are conflicting and have not been reported in humans.8,16,22 Famotidine was not fetally toxic or teratogenic in animal studies. Animal studies of nizatidine have conflicting results. One showed no adverse effects on fetal rat pups, but another study in rabbits given 300 times the recommended dose for humans resulted in abortions, low fetal weights, and fewer live fetuses. Thus, other H 2RAs may be safer than nizatidine.

For women with refractory symptoms despite lifestyle modification and antacid use, H2RAs are commonly used for pregnant women.12 Ranitidine is preferred due to available data, but cimetidine is likely safe. If symptoms persist with antacids, physician referral is advised. A pregnant woman should use the lowest dose necessary (e.g., 75 mg of ranitidine once daily) until she is evaluated by a physician.

Proton-Pump Inhibitors (PPIs)
Omeprazole, the only PPI available OTC, is pregnancy category C. Recent retrospective and prospective cohort studies suggest that usual doses of omeprazole and other PPIs during the first trimester do not present a major teratogenic risk in humans.23-26 A prospective cohort study was conducted on the safety of PPI use in pregnancy.27 In 410 pregnant women taking PPIs (295, omeprazole; 62, lansoprazole; 53, pantoprazole) mostly in the first trimester, the rate of major anomalies was comparable between PPI-exposed women and controls. Although these data suggest safety of use, PPIs should be used during pregnancy with medical supervision and only in women with complicated GERD refractory to other therapies.8,12 These women should be referred to a medical practitioner for further evaluation and management.

In summary, a pregnant woman complaining of GERD or heartburn can be instructed to use nonpharmacologic treatment. Antacid therapy may be recommended if lifestyle modification does not control symptoms. If symptoms continue, low-dose H2RA therapy can be used until she can be seen and evaluated by a physician. Omeprazole OTC should be reserved for patients who are acting on the recommendation of their physician.

Diarrhea is characterized by an increased frequency and decreased consistency of fecal discharge, compared to a normal bowel movement pattern.28 More than three bowel movements per day is considered abnormal.29 Diarrhea is further classified as acute or chronic, based on its onset and duration. Four mechanisms lead to diarrhea: a change in active ion transport by decreased sodium absorption or increased chloride secretion, change in intestinal motility, an increase in luminal osmolarity, and an increase in tissue hydrostatic pressure.28 Diarrhea in pregnancy is typically linked to viral or bacterial infection.30 About 80% of diarrhea episodes are due to viral infection.31 The exact epidemiology of diarrhea in pregnancy is unknown.28 Complications of diarrhea include electrolyte imbalance and dehydration.7

Diarrhea symptoms in pregnancy are similar to those seen in the general population. Patients with acute diarrhea present with increased bowel movements. Acute diarrhea may also present with abrupt onset of nausea, vomiting, abdominal pain, headache, fever, chills, and malaise. Stools have a decreased consistency but are never bloody. It generally lasts 12 to 60 hours. When assessing patients with diarrhea, it is important to inquire about the frequency, volume, consistency, and color of stools.28

Nonpharmacologic Treatment
The first step in treating diarrhea is rehydration of fluids and electrolytes. Oral replacement therapy (ORT) can be used to treat nearly all cases of diarrhea. The World Health Organization recommends oral rehydration solutions that take advantage of the sodium/glucose couples active absorption mechanism. These solutions contain sodium and glucose and are formulated with a concentration and osmolality similar to luminal fluid.30 ORT options include decaffeinated beverages and juices. Sorbitol-containing ORTs should be avoided, as they may worsen preexisting diarrhea. Patients should also be advised to minimize or avoid caffeine, alcohol, and sugary beverage intake, because these products may also worsen preexisting diarrhea. If the patient has worsening diarrhea or is unable to keep up her diarrhea losses, she should be referred to her physician. If the patient has stupor, coma, intestinal ileus, or protracted vomiting, she should be taken to the emergency department for further evaluation.30 Additional questions to ask to determine whether OTC diarrhea treatment or physician referral is necessary are shown in Table 5.

Opiates and Opiate Derivatives
Opiate and opioid derivatives work by delaying the transit of intraluminal content or by increasing gut capacity, prolonging contact and absorption. Most opiates work peripherally and centrally. Loperamide, the only opiate derivative available OTC, is the exception and works peripherally. It has antisecretory effects and works by inhibiting the calcium-binding protein calmodulin and by controlling chloride secretion.28 Loperamide is pregnancy category B, and its use in pregnancy has not been associated with major malformations.30,32 However, one study showed that there may be a link between loper­ amide use and fetal cardiac malformation.31

Adsorbents such as attapulgite, kaolin, polycarbophil, and pectin are used for symptomatic relief in mild diarrhea. There is little evidence of their efficacy, and they may not alter stool frequency, stool fluid losses, or the duration of diarrhea. Adsorbents have a nonspecific mechanism of action. These compounds may adsorb nutrients, toxins, drugs, bacteria, and digestive enzymes in the GI tract. 28 According to the FDA, polycarbophil is the only effective adsorbent agent. Polycarbophil may modify watery stool output by absorbing up to 60 times its weight in water.29 Adverse effects of adsorbents are constipation, bloating, and fullness.28 These products are pregnancy category B.30


Bismuth Subsalicylate
Bismuth subsalicylate has antisecretory, anti-inflammatory, and antibacterial effects. 28 It works by reacting with hydrochloric acid in the stomach to form bismuth oxychloride and salicylic acid.29 It reduces the frequency of unformed stools, increases stool consistency, and relieves symptoms of abdominal cramping, nausea, and vomiting.28 Bismuth subsalicylate is pregnancy category C.30 Similar to other salicylate products, bismuth subsalicylate should not be used in the second and third trimesters due to risks to the mother and fetus. These risks include premature closure of the ductus arteriosus, bleeding, and potential for increased perinatal mortality.33 This product should be used only under the supervision of the patient's physician.31


Digestive Enzymes
Lactobacillus acidophilus is a digestive enzyme that helps shorten the course of diarrhea by restoring the normal flora. It may prevent changes in fecal flora and the resulting diarrhea associated with antibiotics.28 Limited data suggest no link between lactobacillus use and congenital abnormalities, but further research is needed. 34

A variety of OTC products are available to treat diarrhea. Many are pregnancy category B; however, pregnant women should consult their physician prior to using any OTC medications for diarrhea. For pregnant patients with mild diarrhea and minimal dehydration, it is safe to recommend ORT.


Constipation affects 11% to 38% of pregnancies.35 As in GERD, increasing progesterone levels have been implicated in the pathogenesis of constipation. Progesterone can decrease GI motility and may inhibit motilin, which also affects GI transit time.33 The effects of progesterone combined with decreased GI motility can cause constipation during pregnancy. Other predisposing factors for constipation include iron supplementation and an enlarging gravid uterus.33 The symptoms of constipation that a pregnant patient experiences are comparable to those of nonpregnant adults. These include straining, feelings of incomplete evacuation, and changes in stool frequency and/or consistency.12 If a pregnant woman develops abdominal pain, nausea, vomiting, weight loss, rectal bleeding, or cramping with constipation, she should be referred to a physician immediately.29

Nonpharmacologic Treatment
Lifestyle modification is the preferred and safest initial treatment for constipation during pregnancy. Modifications include increasing dietary fiber, liquid intake, and physical activity. Fiber therapy has been shown to increase stool frequency and soften formed stools.35 Yet, there are conflicting data on fiber's efficacy in treating constipation. The type of fiber may be one reason for this discrepancy. Some types of fiber, such as bran, are poorly absorbed. This type is better able to absorb water and is therefore more effective. Sources of fiber include pharmacologic or dietary supplementation. Supplementation should be gradual to lessen bloating and gas. Surprisingly, increasing fluid intake is also controversial. Increased fluids work best for constipated patients who are dehydrated.36 Liquid intake may be compromised by nausea and vomiting, especially in the first trimester. Minimizing the intake of foods that may lead to constipation, such as bananas, cabbage, or beans, may also be beneficial. While controversial, lifestyle and dietary modifications may be sufficient to control mild constipation. Physician referral and drug therapy may be necessary if symptoms are not relieved by these measures (Table 6).

Bulk-Forming Laxatives
Bulk-forming laxatives are advised for use in pregnancy, but most are pregnancy category C. This recommendation is based on their limited systemic absorption and good safety profile. Three common bulk-forming laxatives are available for general use: methylcellulose, polycarbophil, and psyllium. These agents work by increasing the water contained in stool, which improves stool weight and consistency.33 The bulkier stool, in turn, stimulates peristalsis. Paradoxically, the increase in stool consistency is also the reason why these agents can be used for the treatment of diarrhea. Bulk-forming agents can cause flatulence and/or bloating, which may already be a problem for this patient population. These adverse effects can be minimized by increasing fluid intake and by careful dose titration. Increased fluid intake will also decrease esophageal irritation/obstruction. Psyllium has been associated with allergic reactions, including anaphylaxis.12 Common doses are listed in Table 4.

Docusate works differently than other laxatives. Docusate decreases stool surface tension, which increases the fluid content of the stool, thereby softening stools. 33 Docusate is pregnancy category C but undergoes minimal systemic absorption and has not been associated with congenital defects.34,37 To relieve possible constipation with prenatal vitamins, some vitamins also contain docusate. This is an appropriate option after a patient has not achieved relief using nonpharmacologic measures and bulk-forming laxatives.

Stimulant Laxatives
Stimulant laxatives may be reserved for patients whose symptoms do not improve with nonpharmacologic treatment and bulk-forming laxatives or docusate. Their use should be infrequent, not habitual. The most common stimulant laxatives are bisacodyl and senna, which are pregnancy category C. These products act on the colon to stimulate motility. It is this mechanism of action that predisposes them to a higher incidence of diarrhea and abdominal pain than with bulk-forming laxatives.35 Common doses are 5 to 15 mg of bisacodyl orally per day or 10 mg suppository rectally per day and 1 to 2 tablets of senna orally twice daily. Senna has not been shown to be teratogenic in animals or humans.33,34,37

Numerous laxatives are available OTC, but they should be used sparingly. Mineral oil should be avoided, since it can decrease vitamin absorption and may increase the risk of lipid pneumonia. 29,33,38,39 Castor oil may cause uterine contractions and should not be used in pregnancy.33,38 Magnesium and saline laxatives are not recommended in pregnancy because of their potential effects on the patient's electrolyte balance and ability of the latter to cause water retention. 29,33,38 The potential for adverse events due to osmotic laxatives is higher in patients with preexisting renal disease or heart failure.

In summary, constipation during pregnancy should first be treated with nonpharmacologic therapy. Then, products that are not systemically absorbed should be used, such as bulk-forming laxatives. 29,30 Stimulant laxatives are second-line therapy and are recommended only if increased dietary fiber and bulk-forming laxatives fail to relieve constipation. Consultation with a physician is recommended prior to using pharmacologic agents.


Hemorrhoids have been frequently reported in the second and third trimesters of pregnancy. Although the etiology of hemorrhoids is unclear, several factors involved in the pathogenesis are well known. These factors include preexisting bowel disease, a low-fiber diet, straining with defecation, and vascular engorgement due to increased pressure caused by the enlarging abdomen.33

Hemorrhoids can present with symptoms similar to other anorectal disorders. The pharmacist should verify that the patient has had her symptoms evaluated by a physician before recommending a therapy. Swelling, itching, and burning are common symptoms and are similar to symptoms seen in nonpregnant adults.40 Before making any recommendations, the severity of the patient's symptoms should be assessed. Pain, severe symptoms, bleeding, fecal seepage, rectal protrusion, bowel habit changes, and a family history of colon cancer all merit immediate physician evaluation.29

Nonpharmacologic Treatment
As with other GI complaints, hemorrhoids should be treated nonpharmacologically with increasing dietary liquid and fiber. Foods and beverages that cause or aggravate symptoms should be restricted. Soaking in warm water in a sitz bath or a bathtub may also provide relief. Due to the relationship between straining and constipation and hemorrhoids, many treatments for constipation are also appropriate for hemorrhoids. Avoiding constipation and contributing factors to constipation will help improve symptoms. Nonpharmacologic measures that can provide relief are summarized in Table 7.

Pharmacologic Treatment
Local anesthetics, vasoconstrictors, topical corticosteroids, protectants, and astringents may be used to treat hemorrhoids. Topical anesthetics help relieve itching, burning, and pain.33 Absorption is minimal unless the skin is chafed. These products should be applied externally to the skin, and the patient should be counseled to watch for allergic reactions, which may mimic their hemorrhoid symptoms. Some vasoconstrictors are ephedrine, epinephrine, and phenylephrine. These agents decrease swelling but should not be used in pregnant women who have medical conditions that may be exacerbated by vasoconstriction, such as hypertension. It is difficult to assess the safety of vasoconstrictors in pregnancy because they are usually available in combination products. Topical hydrocortisone is another option for pain and itching relief. Several protectant products (e.g., petrolatum) are available and prevent further skin damage by providing a barrier against moisture. Petrolatum has poor absorption and is considered safe in pregnancy.29 Astringents such as witch hazel can sting, which may also exacerbate underlying symptoms. These topical agents have not been adequately evaluated for safety and efficacy in pregnant patients. Of all of these options, topical anesthetics, astringents, and skin protectants are likely the most safe. However, due to limited safety data, these products should be used under a physician's supervision.

Conservative management for hemorrhoids is aimed at pain relief and stool softening. Other options for external hemorrhoids are topical anesthetics, vasoconstrictors, protectants, astringents, and topical corticosteroids. For pain relief, acetaminophen (pregnancy category B) can be recommended. NSAIDs should be avoided, as they may worsen bleeding and are pregnancy category D in the third trimester. Low-strength corticosteroid creams and/or witch hazel can be used for itching. 33 If used, topical corticosteroids should be applied in the smallest amount and for the shortest duration possible. Docusate can also be used to soften stools. Due to the lack of safety information regarding these products in pregnant patients and potential hemorrhoid complications that may be masked by inappropriate treatment, a physician should be consulted prior to recommending OTC products for hemorrhoid treatment.29

Conservative options are recommended to treat hemorrhoids during pregnancy. Since constipation may exacerbate hemorrhoids, prevention and treatment of constipation is also recommended. A physician should be consulted to evaluate other options if pain is not relieved by conservative methods. The patient should contact her physician if symptoms worsen, persist for more than seven days, or if hemorrhoids are linked to severe pain, protrusion, bleeding, or fecal seepage.29

GI Gas
GI gas manifests in two forms: belching and flatulence. Belching, also known as eructation, is the voluntary or involuntary release of gas from the esophagus or stomach. Belching mainly occurs after a meal, due to the relaxation of the LES. Most of the gas in the stomach comes from swallowing air. When too much air is swallowed, an individual may experience flatulence or abdominal pain, as well as belching. Chewing gum, eating rapidly, smoking, and drinking carbonated beverages may contribute to excessive ingestion of air. Flatulence occurs due to gas trapped in the digestive tract, when air is swallowed, or when bacteria in the large intestine breaks down undigested food.41 One study demonstrated that most healthy adults excrete gas an average of 10 times a day; however, other experts state that individuals may pass gas as much as 14 times each day.42,43

Although gas can affect anyone, it can be problematic in pregnant women. One cause is progesterone, which is produced during the early stages of pregnancy. Since progesterone relaxes the smooth muscles, including the intestinal tract, digestion is slowed, leading to increased stomach and intestinal gas. Slowed digestion also gives the intestinal bacteria more time to ferment the undigested food, resulting in more gas production.44

Pharmacologic Treatment
Gas in pregnant women can be treated with nonprescription medications. Some products that contain simethicone, a common treatment for gas, include Gas-X, Phazyme, Mylanta Gas Softgels, and Mylicon drops. This OTC medication relieves gas in the stomach and intestine by reducing the surface tension of gas bubbles. By altering the surface tension, the gas bubbles break and are able to be eliminated by belching or flatulence. Since simethicone is not absorbed from the GI tract, there are no known systemic side effects. It is pregnancy category C, and no congenital defects have been reported.37

Another treatment is alpha-galactosidase. Products that contain this enzyme include Beano and Gaz Away. This OTC medication hydrolyzes high-fiber foods and other foods that contain oligosaccharides before they can be metabolized by the bacteria in the large intestine. The recommended dose is adding about five drops to each serving of problematic food or taking three tablets with each meal. Five drops or three tablets contain 150 units of alpha-galactosidase. Drops should be added to the food after it has cooled. Other OTC options are lactase replacement products, such as Dairy Ease, Lactaid, and SureLac tablets. Lactase replacement may be effective for patients who are intolerant to lactose. These products break down lactose into glucose and galactose and are to be taken when dairy products are ingested. As lactase replacement acts locally in the gut, there are no reported systemic side effects. Pregnant women should check with their physician before taking these OTC medications. 29,45

Many pregnant women can control gas by making dietary changes. Table 8 lists nonpharmacologic approaches to managing gas in pregnancy.29,46 One main change is to limit the amount of gas-producing foods in the diet or totally eliminate foods that are not tolerated.


Pregnant patients may present with a variety of GI complaints. Nonpharmacologic and lifestyle modifications can be recommended with or without concomitant pharmacologic treatment. However, prior to recommending pharmacologic therapy, the patient should be evaluated by a physician. Pharmacists represent a key part of the health care team and can assess whether a pregnant patient's symptoms require immediate physician referral.  Additionally, pharmacists can assist patients and physicians with product selection based on available safety data. Once a product is selected, the pharmacist can counsel the patient on appropriate dosage and usage.

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