Most GI illnesses, particularly the stomach bugs that send people searching for relief, resolve on their own within one to three days. The core of treatment is replacing lost fluids, eating the right foods, and managing symptoms while your body fights off the infection. Viral gastroenteritis is the most common cause, and antibiotics won’t help. Here’s what actually works.
Fluids Come First
Dehydration is the real danger with any GI illness that causes vomiting or diarrhea. Your body loses water, sodium, and potassium rapidly, and replacing those losses is the single most important thing you can do. Plain water helps, but it doesn’t replace electrolytes. Oral rehydration solutions are specifically designed for this: the World Health Organization formula contains about 75 milliequivalents of sodium and 20 milliequivalents of potassium per liter, balanced with glucose to help your intestines absorb the fluid more efficiently.
You don’t need to buy a clinical-grade product. Pedialyte, sports drinks diluted with water, or clear broth all work for mild cases. Sip small amounts frequently rather than gulping large volumes, especially if you’re still nauseous. Ginger ale, chamomile tea, and clear broths can settle your stomach while keeping fluid intake up. Avoid caffeinated drinks like coffee and cola, which can irritate your digestive tract and worsen dehydration.
What to Eat During Recovery
You don’t need to starve yourself, but you do need to be selective. A bland diet lets your gut recover without extra stress. Good options include bananas, applesauce, plain white rice, toast made from refined flour, baked or steamed lean poultry, eggs, broth-based soups, and crackers. Low-fat or fat-free dairy is generally tolerable, though some people temporarily lose the ability to digest lactose after a stomach bug, so pay attention to how milk products make you feel.
Avoid anything that forces your digestive system to work hard: fried or greasy foods, spicy seasonings, raw vegetables, whole grains, nuts, seeds, dried fruits, and alcohol. Gas-producing vegetables like broccoli, cabbage, cauliflower, and green peppers can make cramping worse. Highly processed or sugary foods can also pull water into the intestines and worsen diarrhea. Eat small meals throughout the day rather than a few large ones so your stomach can process food gradually.
Managing Nausea and Vomiting
The vomiting phase is usually the shortest part of a GI illness. Most people throw up repeatedly on the first day, but it typically resolves within 24 to 48 hours. During that window, focus on small sips of clear liquids rather than trying to eat solid food.
Ginger is one of the more reliable natural remedies for nausea. Ginger ale (made with real ginger), ginger tea, or ginger chews can all help. Chamomile tea is another option. Over-the-counter bismuth subsalicylate (the active ingredient in Pepto-Bismol) can ease nausea and settle an upset stomach. Eating something small and bland, like a few plain crackers, once the worst of the vomiting passes gives your stomach something to work with and can reduce that hollow, queasy feeling.
Over-the-Counter Medications
Loperamide (the active ingredient in Imodium) slows down intestinal movement and can reduce the frequency of diarrhea. Adults should not exceed 8 mg (4 tablets) in a 24-hour period for sudden onset diarrhea. It’s useful when you need short-term relief, like getting through a workday, but it works by slowing your gut rather than treating the underlying cause.
Don’t use loperamide if you have a fever, bloody stool, or severe abdominal pain without diarrhea. These could indicate a bacterial infection where slowing the gut down is the wrong move. Bismuth subsalicylate is a gentler option that can help with both diarrhea and nausea, though it may temporarily turn your tongue or stool black (harmless, but surprising).
When Antibiotics Are Actually Needed
The vast majority of GI infections are viral, meaning antibiotics do nothing for them. Even common bacterial causes like Salmonella and Campylobacter are usually self-limiting and don’t require antibiotics. Your immune system handles them on its own.
Antibiotics become appropriate in specific situations: bloody diarrhea, high fever, symptoms in someone with a weakened immune system, significant underlying health conditions, or illness contracted during international travel. If you fall into one of these categories, a stool test can identify the specific pathogen and guide treatment. For everyone else, supportive care (fluids, rest, bland food) is both safer and more effective than unnecessary antibiotics, which can disrupt your gut bacteria and prolong recovery.
Probiotics May Speed Recovery
Certain probiotic strains have evidence behind them for shortening the duration of diarrhea. A large meta-analysis of randomized trials found that Saccharomyces boulardii (a beneficial yeast) shortened diarrhea by about 1.25 days compared to no treatment. Lactobacillus reuteri reduced duration by about 0.84 days, and Bifidobacterium lactis by about one day. Combination probiotics containing Lactobacillus, Bifidobacterium, and Saccharomyces species together showed similar benefits.
These aren’t miracle cures, but shaving a day off a miserable illness is meaningful. Look for products that list specific strains on the label. S. boulardii is widely available and has the strongest evidence for acute diarrhea specifically.
Treating GI Illness in Children
Children, especially young ones, dehydrate faster than adults. The CDC recommends giving children weighing under 10 kg (about 22 pounds) 60 to 120 mL (2 to 4 ounces) of oral rehydration solution after each episode of vomiting or diarrhea. Children over 10 kg should get 120 to 240 mL (4 to 8 ounces) per episode. For mild to moderate dehydration, the guideline is 50 to 100 mL per kilogram of body weight over two to four hours.
Antidiarrheal medications are not recommended for infants and young children. Loperamide in particular carries serious risks in this age group, including dangerous abdominal distension. Bismuth subsalicylate has concerns related to salicylate absorption in children. The focus for kids should stay squarely on fluid replacement and returning to a normal diet as soon as they can tolerate it. Continue breastfeeding or formula feeding throughout the illness.
Warning Signs That Need Medical Attention
Most GI bugs wrap up within a few days. Severe cases can stretch to a week or two, but steady improvement is the expected pattern. Seek medical care if you notice any of the following:
- Signs of dehydration: dry mouth, noticeably decreased urination, rapid heartbeat, lightheadedness when standing, or unusual lethargy
- Bloody diarrhea or vomit
- Fever above 101.3°F (38.5°C) that persists
- Inability to keep any fluids down for more than 24 hours
- Severe abdominal pain that worsens rather than comes and goes with cramping
- Symptoms lasting beyond a week without improvement
In children, watch for fewer wet diapers, crying without tears, sunken eyes, and unusual irritability or listlessness. These signs of dehydration in kids warrant prompt evaluation, as they can deteriorate more quickly than adults.