Safety of Gravol (Dimenhydrinate) During Pregnancy
Gravol (dimenhydrinate) is considered safe for use during pregnancy and is recommended as a first-line pharmacologic antiemetic therapy for nausea and vomiting of pregnancy when non-pharmacological approaches are insufficient. 1
Evidence for Safety
Dimenhydrinate has been extensively studied in pregnancy and demonstrates a favorable safety profile:
The FDA classifies dimenhydrinate as Pregnancy Category B, indicating that reproduction studies in rats and rabbits (at doses up to 20-25 times the human dose) have revealed no evidence of impaired fertility or harm to the fetus 2
Clinical studies in pregnant women have not shown that dimenhydrinate increases the risk of abnormalities when administered during any trimester of pregnancy 2
According to the 2024 American Gastroenterological Association clinical practice update, H1-receptor antagonists including dimenhydrinate are considered safe first-line pharmacologic antiemetic therapies for nausea and vomiting in pregnancy 1
Management Algorithm for Nausea and Vomiting in Pregnancy
Step 1: Non-pharmacological approaches
- Diet and lifestyle modifications:
- Eat frequent small, bland meals
- BRAT diet (bananas, rice, applesauce, toast)
- High-protein, low-fat meals
- Avoid spicy, fatty, acidic, and fried foods
- Identify and avoid specific triggers (foods with strong odors)
Step 2: First-line supplements (if non-pharmacological approaches fail)
- Ginger (250 mg capsule 4 times daily)
- Vitamin B6 (pyridoxine, 10-25 mg every 8 hours)
Step 3: First-line medications (if supplements are insufficient)
- H1-receptor antagonists including dimenhydrinate (Gravol)
- Doxylamine (alone or in combination with pyridoxine)
Important Considerations When Using Gravol in Pregnancy
Dosing: Use the lowest effective dose for the shortest duration necessary to control symptoms
Side effects: Drowsiness is the most common side effect, which may affect the ability to operate vehicles or machinery 2
Breastfeeding: Small amounts of dimenhydrinate are excreted in breast milk. Consider the risk-benefit ratio when using during lactation 2
Labor and delivery: Caution is advised as dimenhydrinate may have an oxytocic effect 2
When to Consider Alternative Treatments
If symptoms are severe and suggest hyperemesis gravidarum (intractable vomiting leading to >5% weight loss, dehydration, and electrolyte imbalances)
If dimenhydrinate is not effective or not tolerated
For persistent symptoms beyond 20 weeks gestation (when most NVP typically resolves)
Gravol represents a safe and effective option for managing nausea and vomiting in pregnancy when non-pharmacological approaches are insufficient, with decades of clinical experience supporting its use in this population.