Bismuth Subsalicylate (BSS) is a common over-the-counter medication used to treat various gastrointestinal complaints. Sold under various brand names, it provides relief from digestive discomforts, including indigestion, upset stomach, nausea, and diarrhea. During pregnancy, the safety profile of many common drugs changes, and expectant mothers must exercise caution. This article examines the safety of BSS use during pregnancy and outlines why this remedy is discouraged for pregnant individuals.
Understanding the Risk Component
The primary concern regarding Bismuth Subsalicylate use in pregnancy stems from the salicylate component. When ingested, BSS quickly hydrolyzes in the stomach, separating into minimally absorbed bismuth and readily absorbed salicylic acid. Salicylic acid is a chemical relative of aspirin and is classified as a non-steroidal anti-inflammatory drug (NSAID). Salicylates interfere with the body’s prostaglandin system, which regulates functions including blood clotting and muscle contraction. The antiplatelet properties of salicylates increase the risk of bleeding for both the mother and the developing fetus. This interference with prostaglandins is directly implicated in severe complications that can affect the fetus, particularly later in gestation, and is the basis for restricting BSS throughout pregnancy.
Trimester-Specific Safety Guidance
The risk associated with BSS use is not uniform across the entire pregnancy, but rather escalates significantly as the due date approaches.
For the first trimester, the period of organ development, caution is advised due to the general association between NSAID exposure and congenital defects. While specific data on BSS and first-trimester defects are not robust, avoiding salicylates during this formative time is a prudent recommendation.
The second trimester is often considered a safer window for certain medications, but Bismuth Subsalicylate is discouraged. Although immediate risks are lower than in the third trimester, the body absorbs the salicylate component, and the risk for complications related to prostaglandin inhibition increases. Healthcare providers recommend avoiding BSS entirely, as safer alternatives are available to manage digestive symptoms.
The third trimester presents the highest risk, and BSS use is strictly contraindicated. Salicylates can cause the premature closure of the fetal ductus arteriosus, a blood vessel that diverts blood away from the lungs while the baby is in the womb. If this vessel closes too early, it can lead to pulmonary hypertension and heart failure in the fetus. Additionally, the antiplatelet effect increases the risk of maternal and fetal bleeding during delivery and can prolong labor.
Safe Alternatives for Digestive Discomfort
Since Bismuth Subsalicylate is not recommended, pregnant individuals should focus on alternative, pregnancy-safe strategies for managing common digestive discomforts.
Heartburn and Indigestion
Over-the-counter antacids containing calcium carbonate, such as Tums, are considered safe and effective. Lifestyle adjustments, such as eating smaller, more frequent meals and remaining upright for at least 30 minutes after eating, can also reduce symptoms.
Gas and Bloating
Simethicone (Gas-X) is an effective and non-absorbed option for gas and bloating, a common complaint due to hormonal changes. Increasing fluid intake and incorporating more dietary fiber helps manage constipation, which contributes to gas. A gentle stool softener like docusate may be recommended by an obstetrician.
Nausea and Diarrhea
Nausea, especially during the first trimester, can often be managed with Pyridoxine (Vitamin B6), an American College of Obstetricians and Gynecologists (ACOG) recommended first-line treatment. Medications for diarrhea should be selected with guidance from a healthcare provider, but simple dietary changes and increased hydration are initial steps. Always consult with an obstetrician before starting any new medication.