Vomiting and Diarrhea

Symptoms

• Nausea and vomiting: A queasy stomach with repeated episodes of throwing up, often the body's first response to an infection or spoiled food.
• Watery diarrhea: Frequent loose or watery stools, sometimes with urgency and cramping.
• Abdominal cramps: Waves of belly pain or spasms that may ease briefly after vomiting or a bowel movement.
• Low-grade fever: A mild rise in temperature is common with viral gastroenteritis and often passes on its own.
• Signs of dehydration: Increased thirst, dry mouth, reduced or dark urine, headache, dizziness, and tiredness as fluid is lost.
• Loss of appetite: Not wanting to eat or drink, which can make fluid loss worse if it continues.

When it's an emergency

Come in now or come to Bellaire ER immediately if you cannot keep any liquids down, vomit blood or material that looks like coffee grounds, or pass stool that is bloody, maroon, or black and tarry. These can signal internal bleeding or a serious gastrointestinal problem.

Seek emergency care for severe or worsening abdominal pain, a high or persistent fever, a stiff neck, confusion, or severe weakness. Come in now if vomiting occurs alongside sudden severe headache, chest pain, one-sided weakness, or slurred speech, which can signal a stroke or heart problem rather than a stomach bug.

Dehydration red flags vary by age. In infants and young children, watch for no wet diaper in six to eight hours, no tears when crying, a sunken soft spot, dry mouth, sunken eyes, and unusual drowsiness or floppiness. In older adults and anyone with a chronic illness, watch for confusion, rapid heartbeat, lightheadedness on standing, very dark urine, and little or no urination.

Don't wait it out if symptoms last more than two to three days, if a young child, older adult, pregnant person, or someone with diabetes or a weakened immune system cannot stay hydrated. Prolonged fluid loss can cause dangerous dehydration and electrolyte imbalances that need prompt IV treatment.

When it's not an emergency

Most stomach bugs and mild food poisoning can be managed at home. Rest, sip an oral rehydration solution or clear fluids frequently in small amounts, and return to bland foods as tolerated. Symptoms usually improve within one to three days.

Bellaire ER's virtual urgent care is reasonable when vomiting and diarrhea are mild, you are keeping some fluids down, and there are no red flags. A clinician can advise on rehydration, anti-nausea options, and whether testing is needed. Bellaire ER also offers telemedicine for exactly this kind of guidance.

Contact your primary care doctor if you have ongoing symptoms without warning signs, need a note, or want help judging your child's hydration. When you are unsure or symptoms are worsening, an ER visit is the safer choice.

What else could be causing this

Viral gastroenteritis

Norovirus in adults, rotavirus in young children, and a handful of others. The illness arrives abruptly, tends to peak within a day, and runs its course in one to three days. There is usually no blood in the stool and only a low-grade fever, and the real hazard is the fluid lost rather than the virus itself.

Bacterial food poisoning

Salmonella, Campylobacter, Shigella and some E. coli strains, from undercooked poultry or meat, unpasteurized dairy or contaminated produce. Fever is more prominent than with a virus, the illness lasts longer, and blood or mucus in the stool is far more likely. Several people who ate the same meal falling ill together is a strong clue.

Preformed toxin in food

Staphylococcus aureus or Bacillus cereus multiplying in food left at room temperature. Because the toxin is already present when you eat it, vomiting starts within one to six hours rather than the next day, and it typically resolves inside 24 hours. The short gap between the meal and the symptoms is what identifies it.

Parasitic infection and travelers' diarrhea

Giardia, Cryptosporidium and similar organisms, picked up from untreated water, swimming, or travel to areas with less reliable water treatment. The pattern is different from a virus: diarrhea that drags on for weeks, often with bloating, foul-smelling stools and weight loss rather than a brief sharp illness. It needs identification and specific treatment.

Antibiotics and other medications

Antibiotics disrupt normal gut bacteria and commonly loosen stools; Clostridioides difficile can take hold during or in the weeks after a course and causes watery diarrhea with cramping and fever. Metformin, chemotherapy, laxatives, magnesium-containing antacids and several other drugs do the same by a different route. Any new medication in the last month is relevant history.

Appendicitis and other surgical causes of abdominal pain

Appendicitis, a twisted ovary, a strangulated hernia and similar problems frequently open with nausea and vomiting, which is why they get mistaken for a stomach bug on day one. What distinguishes them is pain that becomes the main symptom, localizes to one area, worsens steadily, and hurts on movement or coughing. Pain that is outgrowing the vomiting is the pattern that needs imaging.

Bowel obstruction

A mechanical blockage, most often from scar tissue after previous abdominal surgery or a hernia. Vomiting is persistent and may become bilious, the abdomen swells and becomes tympanic, and gas and stool stop passing, the reverse of gastroenteritis, where diarrhea is the complaint. This is a surgical diagnosis and a reason imaging is done early.

Pancreatitis and gallbladder disease

Severe upper abdominal pain with relentless vomiting, often boring through to the back in pancreatitis, or in the right upper abdomen after a fatty meal in gallbladder disease. Gallstones and alcohol account for most pancreatitis. Diarrhea is not typical, and the pain is out of proportion to the gut symptoms.

Causes outside the gut entirely

Vomiting is a general alarm, not a gut-specific one. A kidney infection, diabetic ketoacidosis, a heart attack, raised pressure inside the skull, a stroke, pregnancy and severe vertigo all produce it. Vomiting with sudden severe headache, chest pain, one-sided weakness, slurred speech or a stiff neck is treated as an emergency of that system rather than a stomach bug.

What happens when you arrive

When you arrive at Bellaire ER with vomiting and diarrhea, a board-certified emergency physician assesses how dehydrated you are. Your evaluation may include a physical exam, blood and urine labs to check electrolytes, kidney function, and signs of infection, and stool testing when indicated.

Imaging such as ultrasound, X-ray, or CT is available on-site if the physician needs to rule out appendicitis, a bowel obstruction, or another abdominal cause. If you are dehydrated, we can start IV fluids to rehydrate you and give medication through the IV to control nausea and vomiting.

We diagnose and treat in a single visit, and most patients do not need a hospital transfer. Before you leave, your physician explains your results, provides prescriptions if needed, and gives a clear plan for rehydration, diet, and follow-up.

Tests we can run on site

Basic metabolic panel

Sodium, potassium, chloride, bicarbonate, glucose and kidney function. It quantifies what the vomiting and diarrhea have actually cost you, shows whether the kidneys are affected, and flags the acid-base picture of diabetic ketoacidosis.

Complete blood count

A markedly raised white cell count points toward a bacterial infection or an inflammatory process such as appendicitis rather than a virus. The red cell values help judge how concentrated the blood has become, and a low count raises the question of bleeding.

Lipase

An enzyme that rises sharply in pancreatitis. It is the test that separates severe upper abdominal pain with vomiting from a gut infection, and it is run whenever the pain is central or upper and out of proportion to the diarrhea.

Urinalysis

Looks for a urinary tract or kidney infection presenting as vomiting, and measures ketones and urine concentration as a marker of dehydration. In older adults especially, this test redirects the diagnosis often enough to be routine.

Stool testing

Used when the stool is bloody, the illness has run beyond a few days, antibiotics were taken recently, or there has been foreign travel. It identifies bacterial pathogens, parasites and C. difficile, all of which change treatment from fluids alone to specific therapy.

Pregnancy test

Run for anyone of childbearing age with vomiting or abdominal pain. It is not about explaining the nausea; it is to exclude an ectopic pregnancy and to determine which imaging is appropriate.

Ultrasound and CT

Ultrasound uses sound waves with no radiation and is the first choice for the gallbladder, kidneys and ovaries, and in children and pregnancy. CT gives a cross-sectional view of the whole abdomen and is used when appendicitis, an obstruction, diverticulitis or an abscess is a real possibility.

Treated here, or transferred

Bellaire ER is a licensed freestanding emergency room: board-certified emergency physicians and nurse practitioners, on-site CT, X-ray, ultrasound and laboratory, medication administered during your visit, open 24 hours a day, 365 days a year, for adults and children. It is built to evaluate, stabilize and treat emergencies, and it is not a hospital. Most vomiting and diarrhea falls well inside what it handles start to finish.

The treatment that matters most is fluid. Intravenous fluids replace losses that sipping cannot keep up with, and they work when drinking has stopped working. Anti-nausea medication given through the same line usually interrupts the cycle where every mouthful comes straight back. Which is the practical reason home rehydration fails rather than any failure of effort. Electrolyte abnormalities found on the blood work are corrected here, antibiotics are given when a bacterial or parasitic cause is identified rather than suspected, and medication to continue at home is written as a prescription for you to fill at your own pharmacy.

Some causes need a hospital, and the evaluation here is what identifies them. A bowel obstruction, appendicitis or a perforation needs an operating room; severe pancreatitis, significant kidney injury, gastrointestinal bleeding, or diabetic ketoacidosis needing an insulin infusion needs admission. A freestanding emergency room has no operating room, no intensive care unit and no inpatient beds. In those cases the imaging, the labs, the fluids and the first doses of medication happen here, and care continues without interruption during transfer to a hospital with the service required. Transfer is a routine part of how this works, not a failure of the visit.

If the picture is infectious and self-limited, your physician explains what was excluded and why, what the next few days should look like, and the specific symptoms that mean you should come back.

Children

Bellaire ER treats adults and children. In a child, the illness is rarely the danger, the speed of fluid loss is. Children have a smaller fluid reserve relative to their size, so the same number of episodes dehydrates a toddler far faster than an adult, and an infant can slide from mildly unwell to significantly dehydrated within hours.

The signs to watch in a baby or toddler are fewer wet diapers than usual, with none in six to eight hours being a clear red flag; no tears when crying; a dry mouth; a sunken soft spot on the head; sunken eyes; and a child who is floppy, unusually sleepy or hard to wake. A child who refuses all fluids, or who vomits back every attempt, should be seen rather than watched. Any infant under three months with a rectal temperature of 100.4 degrees Fahrenheit or higher needs emergency evaluation whatever the gut symptoms are doing.

Offer an oral rehydration solution, in very small amounts very often, a teaspoon every few minutes gets further than a cup that comes straight back. Plain water alone, juice, soda and sports drinks are poor substitutes because the sugar and salt balance is wrong and can make the diarrhea worse. Over-the-counter anti-diarrheal medicines are not given to young children.

Bring a child in for green or bile-stained vomit, blood in the stool, stool that looks like red currant jelly, a swollen or very tender abdomen, episodes of inconsolable crying with drawing up of the knees, or diarrhea lasting beyond a week. When imaging is needed in a child, laboratory testing and ultrasound are used first, before CT.

After you leave

Getting better usually happens in stages rather than all at once. Vomiting generally settles first; loose stools can carry on for several days after you otherwise feel well, and mild cramping and a poor appetite in that window are expected. Tiredness often outlasts the gut symptoms by a week or more, which is normal.

Keep drinking after you leave, in small amounts frequently rather than a large glass at once. An oral rehydration solution replaces the salts you lost as well as the water, which plain water does not. Eat when you want to, starting simple, and do not hold yourself to a restrictive diet, returning to normal food as tolerated is reasonable and speeds recovery. Leave alcohol, caffeine and heavy fatty meals for a few days. Wash hands with soap and water rather than relying on alcohol gel, which does not reliably kill norovirus, and do not prepare food for others until two days after symptoms stop.

Come back, or call 911 if you cannot travel safely, if you stop being able to keep fluids down, if you stop urinating or pass only small amounts of very dark urine, or if you become lightheaded on standing, confused or hard to rouse. Return for blood in the vomit or stool, black tarry stool, a fever above 103 degrees Fahrenheit, or abdominal pain that becomes severe, constant, or concentrates in one place. Pain that is worsening while the diarrhea improves is the specific change that should bring you back in.

Take what you were given as directed and finish any antibiotic course. Keep the follow-up appointment you were advised to make, and if a stool sample was sent, chase the result rather than assuming silence means normal.

Lowering your risk

Wash your hands thoroughly with soap and water after using the bathroom, changing diapers, and before preparing or eating food, since many stomach bugs spread this way and alcohol gels are less effective against some of them.

Practice food safety: refrigerate leftovers promptly, cook meats to safe temperatures, avoid cross-contamination between raw and cooked foods, and be cautious with unpasteurized products and untreated water.

During an active illness, keep the sick person's towels and utensils separate and disinfect surfaces to protect the rest of the household. A rotavirus vaccine is recommended for infants to prevent one common cause of severe diarrhea.