On call for my patients, I get a call about flu.
The spouse sounds worried. I speak to the sick person.
"Do you have a fever?"
"Yes, 100.6. I am throwing up and I don't want to eat."
"Do you have muscle aches?"
"Not really. I know I need to drink water."
"Are you coughing?"
"Not really. Not much."
"Not very congested. Do you have diarrhea?"
"Yes, lots. And my stomach hurts when I eat."
People often say "flu" meaning "stomach flu" which is not influenza. "Stomach flu" is gastroenteritis, another set of viruses entirely. It could be a bacterial food poisoning, but in 17 years in my rural town, I have seen a total of two food poisoning bacterial infections. Most here are viral.
"Is there blood in the diarrhea?"
Viral, then. Blood in the stool is more likely to be bacterial.
The important thing is to stay hydrated. If the person gets too dehydrated, they tend to just keep throwing up and may need iv fluids. To keep them out of the emergency room, I give the following recipe:
One quart of water
one teaspoon sugar
A pinch of salt
(with or without a pinch of baking soda)
If the person is quite nauseated, try drinking just a tablespoon every 15 minutes, with a timer. The electrolytes and sugar help the fluids absorb. Small amounts are easier to absorb and less likely to come up. If they keep throwing that up, go to the emergency room.
"I'm not eating."
That's ok. A day without eating won't hurt you unless you are starting very underweight. Get the fluids in first and then you can go on to chicken soup and try some crackers.
Gatorade or flat ginger ale or pedialyte contain electrolytes too, but the home recipe is fine. And for small children, regular or pedialyte popsicles, because they can't really drink them quickly.
Most people will recover on their own, especially if they stay hydrated. We don't tend to try to stop the diarrhea, it's better just to hydrate people to keep up. If someone is immunosupressed, on chemotherapy or with HIV or after a transplant, they may need hospitalization.