Most food poisoning resolves on its own within one to three days, but the right medicine can make those miserable hours more bearable. What you should take depends on your specific symptoms, whether you’re dealing with diarrhea, nausea, cramping, or all three, and on a few important safety signals your body may be sending.
OTC Medicines for Diarrhea and Nausea
Two over-the-counter options cover the most common food poisoning symptoms. Loperamide (sold as Imodium A-D) slows gut contractions to reduce watery diarrhea. Bismuth subsalicylate (Pepto-Bismol, Kaopectate) targets the broader picture: nausea, upset stomach, and loose stools. Both are available without a prescription and are generally the first line of relief for adults with uncomplicated food poisoning.
There’s an important catch. Loperamide is only appropriate when your stools aren’t bloody and you don’t have a fever. The FDA labels it as unsuitable for acute dysentery (bloody diarrhea with high fever) or for infections caused by invasive bacteria like Salmonella, Shigella, or Campylobacter. In those situations, slowing your gut down can actually trap the bacteria inside longer and make things worse. If your diarrhea doesn’t improve within 48 hours, or you notice blood in your stools or develop a fever, stop taking it.
What Not to Give Children
Neither loperamide nor bismuth subsalicylate is recommended for children. Bismuth subsalicylate carries a specific risk: it’s chemically related to aspirin, and giving it to a child or teenager who has or is recovering from a viral infection raises the risk of Reye’s syndrome, a rare but serious condition affecting the brain and liver. Children with bleeding problems, ulcers, or aspirin allergies should also avoid it entirely. For kids with food poisoning, oral rehydration solutions are the safest first step.
Prescription Anti-Nausea Medication
When vomiting is severe enough that you can’t keep fluids down, a doctor may prescribe an anti-nausea medication. Ondansetron is the one most commonly used in emergency departments for gastroenteritis-related vomiting. In clinical trials, patients who took it were about 50% more likely to stop vomiting within the first hour compared to those given a placebo, and they were significantly less likely to need IV fluids for rehydration. One trade-off: ondansetron can worsen diarrhea, so it’s typically reserved for situations where vomiting is the dominant problem and dehydration is a real concern.
When Antibiotics Are Needed
Most food poisoning is self-limiting, meaning your immune system clears the infection without antibiotics. In fact, for some bacteria, antibiotics can do more harm than good. E. coli O157:H7, the strain behind some of the most publicized outbreaks, is a case where studies suggest antibiotics may actually be harmful.
Antibiotics become appropriate in specific situations, usually when lab tests identify a particular bacterium and the infection is severe or spreading beyond the gut. Shigella infections are commonly treated with antibiotics when the organism is confirmed. Campylobacter may warrant antibiotics if caught early in severe cases. Salmonella typically doesn’t need antibiotic treatment unless the infection has spread to the bloodstream or other organs, or the patient is at high risk for that happening. Listeria, which is especially dangerous for pregnant women and people with weakened immune systems, requires antibiotics for invasive disease.
The decision to prescribe antibiotics depends on which organism is involved, how sick you are, and susceptibility testing. This is why a doctor will sometimes order a stool culture before deciding on treatment rather than prescribing antibiotics right away.
Ginger for Nausea Relief
If you’d rather start with something gentler, ginger has legitimate evidence behind it. In a clinical study of patients in acute care settings, inhaled ginger essential oil reduced nausea severity from an average score of 1.73 to 0.68 within 30 minutes. For 67% of participants, the relief lasted six hours or longer, comparable to standard anti-nausea medication. Peppermint, spearmint, and cardamom oils have also shown benefit for nausea in clinical research. Ginger tea or ginger chews are easy, low-risk options while you’re waiting for symptoms to pass.
Probiotics and Recovery Time
Certain probiotic strains can shorten the duration of infectious diarrhea. In a randomized controlled trial comparing probiotics to standard rehydration therapy alone, one well-studied strain (Lactobacillus rhamnosus GG) reduced the average duration of diarrhea by nearly 19 hours and shortened hospital stays. Not all probiotics performed equally in the same trial; results varied by strain. If you decide to try a probiotic, look for products that list the specific strain on the label rather than just a general species name.
Rehydration: The Most Important “Medicine”
No pill matters as much as replacing lost fluids and electrolytes. Vomiting and diarrhea drain water, sodium, and potassium rapidly, and dehydration is the main reason food poisoning becomes dangerous. Oral rehydration solutions are the gold standard, but clear broths, diluted juice, and water with a pinch of salt also help. Sip small amounts frequently rather than drinking large volumes at once, especially if you’re still vomiting.
Watch for signs that dehydration is getting ahead of you: urinating very little, a dry mouth and throat, or feeling dizzy when you stand up. Combined with bloody diarrhea, a fever over 102°F, vomiting so persistent you can’t keep any liquids down, or diarrhea lasting more than three days, these are signals to get medical help rather than managing things at home.