Best over-the-counter options for food poisoning

Replaces the water, sodium and potassium you are losing in stool and vomit, in the specific sugar-to-salt ratio that lets the gut absorb water even while it is inflamed. This is the actual treatment for food poisoning — it does not kill the germ, it keeps the dehydration from becoming the thing that hurts you. Buy the ready-mixed commercial product; do not improvise one at the kitchen counter. For a child who is vomiting, give it in small, frequent sips rather than a glass at a time.

CDC's food poisoning page: "If you have diarrhea or vomiting, be sure to drink plenty of fluids to prevent dehydration (not having enough water in your body)." CDC's E. coli risk page names the products: "Diarrhea in young children can be very serious. Give children with diarrhea extra fluids, such as Pedialyte® or oral rehydration salts. Do not wait." The American Academy of Pediatrics is explicit that ordinary drinks are not a substitute: "Electrolyte solutions are special fluids that have been designed to replace water and salts lost during diarrhea. Soft drinks (soda, pop), soups, juices, sports drinks, and boiled milk have the wrong amounts of sugar and salt and may make your child sicker." AAP also warns: "Do not try to prepare your own electrolyte solutions at home. Use only commercially available fluids—store brand and name brand work the same." AAP's home dosing table for mild diarrhea gives 40 oz of electrolyte solution per 24 hours for a 22-lb child, 51 oz for a 33-lb child, and 61 oz for a 40-lb child.

Caution: A sports drink is not an ORS — AAP lists sports drinks among the fluids that "may make your child sicker." Hydration-multiplier powders sold on the same shelf (Liquid I.V. and similar) are marketed for general hydration and are not oral rehydration solution; no source cited here endorses them for diarrhea, and CDC names "Pedialyte® or oral rehydration salts." Plain water and tea are also wrong for heavy losses; AAP says children with severe diarrhea "need to avoid liquids that are high in sugar, high in salt, or very low in salt (ie, water and tea)." ORS cannot fix vomiting severe enough that nothing stays down — CDC lists "Vomiting so often that you cannot keep liquids down" as a reason to see a doctor, and MedlinePlus notes you may then need "fluids through a vein (IV)." Breastfed infants should keep breastfeeding. If you take diuretics or ACE inhibitors, MedlinePlus advises contacting your provider, as "You may need to stop taking these medicines while you have diarrhea."

Slows gut motility so stool spends longer in the intestine and you go less often. It treats the symptom, not the infection, and by slowing transit it can keep the organism and its toxin in contact with your gut lining longer — which is exactly why the FDA prescription label for loperamide contraindicates it outright in bacterial enterocolitis caused by invasive organisms. It is an option only for a healthy adult with watery, non-bloody, fever-free diarrhea in whom an invasive or antibiotic-associated infection is not suspected, and mostly as a way to get through a flight or a workday. Not the move for anything that looks invasive.

The OTC Drug Facts label states under Do not use: "if you have bloody or black stool," and under Ask a doctor before use if you have: "fever," "mucus in the stool," "a history of liver disease," "a history of abnormal heart rhythm." The FDA prescription label for the same molecule is more specific: "Loperamide hydrochloride capsules are contraindicated in: pediatric patients less than 2 years of age due to the risks of respiratory depression and serious cardiac adverse reactions; ... patients with abdominal pain in the absence of diarrhea; patients with acute dysentery, which is characterized by blood in stools and high fever; patients with acute ulcerative colitis; patients with bacterial enterocolitis caused by invasive organisms including Salmonella, Shigella, and Campylobacter; patients with pseudomembranous colitis (e.g., Clostridium difficile) associated with the use of broad-spectrum antibiotics." CDC's E. coli treatment guidance adds: "Do not use anti-diarrheal medication with high fever or bloody diarrhea" and "Do not use anti-diarrheal medication with Shiga toxin-producing E. coli (STEC) infection. Using anti-diarrheal medication with STEC infection can increase the chance of hemolytic uremic syndrome (HUS)." CDC is also candid about the trade-off even when it is safe: "Taking anti-diarrheal medication might help with diarrhea and cramps, but it might make your illness last longer."

Caution: The absence of visible blood and fever does not clear you. CDC's own onset table gives Salmonella "6 hours to 6 days" and Campylobacter "2 to 5 days," and both start as watery diarrhea before blood or fever appear — so a first-day screen can look clean while you are squarely inside the labeled contraindication for invasive bacterial enterocolitis. If your diarrhea started during or within weeks after a course of antibiotics, do not take loperamide at all: the label contraindicates it in pseudomembranous colitis associated with broad-spectrum antibiotics, and that needs testing, not motility slowing. Adult dose is capped hard: "2 caplets after the first loose stool; 1 caplet after each subsequent loose stool; but no more than 4 caplets in 24 hours" — 8 mg total. The label carries a Heart alert: "Taking more than directed can cause serious heart problems or death." Do not give it to children with suspected food poisoning. The label says children under 2 (up to 33 lbs): "do not use," and ages 2–5 (34–47 lbs): "ask a doctor"; MedlinePlus goes further for bacterial gastroenteritis specifically — "Do not give these medicines to children" — and AAP says "Over-the-counter antidiarrheal medicines are not recommended for children younger than 2 years. They can also be harmful in older children." Children under 5 are CDC's top risk group for STEC and HUS, which is the whole reason. Stop and call a doctor if "symptoms get worse," "diarrhea lasts for more than 2 days," or "you get abdominal swelling or bulging. These may be signs of a serious condition." Check with a pharmacist first if you take prescription drugs — the label warns "Loperamide may interact with certain prescription drugs."

The one OTC here whose label covers both ends of the illness — it is marketed for diarrhea and for the nausea/upset-stomach half. Unlike loperamide it is not primarily a motility blocker. It is a salicylate, chemically an aspirin relative, and that is where every one of its restrictions comes from.

The Pepto-Bismol Drug Facts label lists as Uses: "Relieves • travelers' diarrhea • diarrhea • upset stomach due to overindulgence in food and drink, including: • heartburn • indigestion • nausea • gas • belching • fullness." Its Reye's syndrome warning reads: "Children and teenagers who have or are recovering from chicken pox or flu-like symptoms should not use this product." Allergy alert: "Contains salicylate. Do not take if you are • allergic to salicylates (including aspirin) • taking other salicylate products." CDC states: "Do not use anti-diarrheal medication containing bismuth subsalicylate with children younger than 12. Medications with bismuth subsalicylate include Pepto-Bismol® and Kaopectate®." CDC's Yellow Book chapter on travelers' diarrhea sets out the exclusions: "Travelers with aspirin allergy, gout, or renal insufficiency and those taking anticoagulants, methotrexate, or probenecid should not take BSS," and "BSS is not recommended for children aged <3 years or pregnant women."

Caution: CDC's do-not-use rule for anti-diarrheal medication covers this drug, not just loperamide: CDC defines the class to include it — "Medications with bismuth subsalicylate include Pepto-Bismol® and Kaopectate®" — and says "Do not use anti-diarrheal medication with high fever or bloody diarrhea." That is stricter than the label's own softer "ask a doctor before use if you have" "fever" or "mucus in the stool," and fever plus nausea plus diarrhea is the commonest food-poisoning picture there is. Do not take it if you are pregnant: CDC's Yellow Book says bismuth subsalicylate "is not recommended for children aged <3 years or pregnant women," and the label's own line is "If pregnant or breast-feeding, ask a health professional before use." Each 262 mg chewable contains "salicylate 101 mg," and the maximum is "2 tablets every 1/2 to 1 hour as needed • do not exceed 8 doses (16 tablets) in 24 hours • use until diarrhea stops but not more than 2 days" — 16 tablets is about 1,616 mg of salicylate, which is why the aspirin-allergy and blood-thinner rules are absolute. Do not use "if you have • an ulcer • a bleeding problem • bloody or black stool." Ask a doctor or pharmacist first if you take "any drug for • anticoagulation (thinning the blood) • diabetes • gout • arthritis." Stop if "ringing in the ears or loss of hearing occurs" — that is salicylate toxicity. The label notes a "temporary, but harmless, darkening of the stool and/or tongue may occur," but you cannot tell that darkening apart from melena at your own toilet, and this is a salicylate, which can cause or worsen an upper-GI bleed. MedlinePlus says to contact your provider if "Blood or pus in your stools, or your stool is black." So: black or tarry stool while taking it means stop the drug and get evaluated, not reassure yourself. Children under 12: the label says ask a doctor, CDC says do not.

These are antihistamine antiemetics aimed at the inner-ear/vestibular pathway. That is the pathway of seasickness and car sickness, not the pathway of a toxin or virus irritating your gut. People grab them because the box says "antiemetic" and "nausea, vomiting," but neither label lists gastroenteritis, food poisoning, or stomach flu as a use. Mostly what you get from them is sedation. If you are vomiting badly enough that nothing stays down, the answer is a visit, not another box from this aisle.

Bonine (meclizine HCl 25 mg) Drug Facts, Uses: "prevents and treats nausea, vomiting or dizziness associated with motion sickness." Dramamine Original Formula (dimenhydrinate 50 mg) Drug Facts, Use: "for prevention and treatment of these symptoms associated with motion sickness: • nausea • vomiting • dizziness." Neither FDA label names food poisoning or gastroenteritis; both are OTC Monograph M009 antiemetic products whose labeled indication is motion sickness only. There is no FDA-labeled indication for foodborne illness — not weak evidence, no indication.

Caution: If you take them anyway for the drowsiness, know the label limits. Dramamine: "do not give to children under 2 years of age unless directed by a doctor"; adults and children 12+ take 1 to 2 tablets every 4–6 hours, no more than 8 tablets in 24 hours; The pediatric bands printed on that carton are motion-sickness dosing and do not belong on this page: do not give a child an OTC antiemetic for food poisoning. AAP: "In most cases, vomiting will stop without specific medical treatment... you should never use over-the-counter or prescription remedies unless they’ve been specifically prescribed by your pediatrician for your child and for this particular illness." Bonine: "Do not use in children under 12 years of age unless directed by a doctor"; "adults and children 12 years and over: take 1 to 2 chewable tablets once daily or as directed by a doctor." Both labels say to ask a doctor first if you have "glaucoma" or "a breathing problem such as emphysema or chronic bronchitis," and both flag trouble urinating from an enlarged prostate — Bonine's wording is "difficulty in urination due to enlargement of the prostate gland," Dramamine's is "trouble urinating due to an enlarged prostate gland." Both say to avoid alcohol, sedatives and tranquilizers. Dramamine warns "marked drowsiness may occur" — dangerous if you are already lightheaded from dehydration. If nothing stays down, an antihistamine is not the answer: MedlinePlus's page "When you have nausea and vomiting" says to contact your provider if you or your child "Cannot keep any food or liquid down," "Vomit three or more times in one day," "Have nausea for more than 48 hours," or "Have not urinated for 8 hours or more."

Most food poisoning is self-limited and needs neither. A clinician may test a stool sample, give IV fluids, prescribe something for nausea so you can hold down oral fluids, or in specific severe or high-risk cases prescribe an antibiotic. The reason this is not a self-treat item is that in one common and dangerous scenario — Shiga toxin-producing E. coli — antibiotics make the outcome worse, and only testing tells you which infection you have.

CDC: "Do not use antibiotics with STEC infection. Using antibiotics with STEC infection can increase the chance of HUS," and "Most people get better without using antibiotics." MedlinePlus, on bacterial gastroenteritis: "Antibiotics are not given very often for most common types of bacterial gastroenteritis. If diarrhea is very severe or you have a weak immune system, antibiotics may be needed." On stakes: CDC's food poisoning symptoms page says "Around 5–10% of people diagnosed with E. coli develop a life-threatening health problem called hemolytic uremic syndrome," and CDC's About E. coli page spells out the outcome — "HUS can lead to kidney failure, permanent health problems, and even death."

Caution: Never take leftover antibiotics from a previous illness or someone else's prescription for diarrhea — you cannot tell Salmonella from Campylobacter from STEC by symptoms, and CDC's E. coli guidance also says to "Call the doctor before using anti-diarrheal medication." Do not wait out a full three days if you are in a group CDC's About E. coli and risk-factors pages flag as higher risk — "Children younger than 5," "Adults 65 and older," "People with weakened immune systems," "International travelers." CDC's E. coli risk page uses a shorter trigger for everyone: contact a provider for "Diarrhea or vomiting lasting more than 2 days," "Bloody poop or pee," "A fever higher than 102°F," "Signs of dehydration" or "Signs of hemolytic uremic syndrome."