Best OTC Medicines for Digestive (GI)
Common over-the-counter options for digestive (gi), with typical adult dosing and key safety notes.
Medically reviewed by a licensed pharmacist · Last reviewed
Reviewed against: FDA OTC Monograph
Activated Charcoal
25-50g by mouth as a single dose, or 25g every 2-4 hours for multiple doses. Mix with water to form slurry. Take 1-2 hours away from other medications and food.
Alpha Galactosidase
300-1200 units by mouth with first bite of gas-producing foods. Adjust dose based on meal size and individual response. No maximum daily limit established.
Bismuth Subsalicylate
30mL liquid OR 2 tablets every 30-60 minutes as needed. Max 8 doses (240mL or 16 tablets) in 24 hours. Do not use longer than 2 days.
Ginger
250mg standardized ginger extract by mouth up to 4 times daily, OR sip ginger tea, OR chew crystallized ginger as tolerated. Max 1g/day in pregnancy.
Lactase Enzyme
Follow package directions, typically 3000-9000 FCC units taken with first bite of dairy-containing food. Dose varies by lactose content of meal.
Loperamide
4mg initial dose, then 2mg after each loose stool. Max 8mg/day OTC, max 2 days of self-treatment.
Oral Rehydration Salts
Sip 1-2 cups (240-480mL) of prepared oral rehydration solution (Pedialyte, DripDrop) after each loose stool or vomiting episode. Aim for 1 cup/hour while symptomatic.
Peppermint Oil Enteric
0.2-0.4mL enteric-coated capsules by mouth 3 times daily, 30-60 minutes before meals. Max 1.2mL/day. Take with water, do not chew or crush capsules.
Probiotic Lactobacillus
1-10 billion CFU by mouth once daily. Take with or after meals for better survival. Refrigerate if specified on label. May cause mild bloating initially.
Simethicone
40-125mg by mouth after meals and at bedtime as needed. Max 500mg/day. Chew thoroughly.
This page is for general education and is not medical advice. It does not replace a consultation with a licensed pharmacist or your clinician. Always read and follow the product label. If symptoms are severe, worsening, or persistent, seek professional care.