Hi,

It appears you are having an episode of viral gastroenteritis (stomach flu). This presents with vomiting and diarrhoea, which may be preceded by headaches and flu like symptoms.

Treatment for this is mainly supportive:

Rest.
Plenty of fluids.
Bland diet.
Small meals.

You can take the following OTC medicines:

Loperamide (one brand name: Imodium): the dosage is 2 caplets after the first loose stool, then 1 caplet after each loose stool that follows. Take no more than 4 caplets or 8 teaspoonfuls in 24 hours

Bismuth subsalicylate (brand names: Kaopectate, Pepto-Bismol): The usual dose is 2 tablespoonfuls every half-hour to one hour if needed. You should not take more than 16 tablespoonfuls of the regular-strength suspension or 8 tablespoonfuls of the concentrate in twenty-four hours

You will need to report to the doctor if your diarrhea is so severe you get dehydrated, or you pass blood in vomit or stools. Viral gastroenteritis usually resolves spontaneously. However, passing of blood is a worrying factor. If you find that you are still passing blood you should consult your family physician or PCP tomorrow. You may need antibiotics and stool culture. If you have more than 1 or 2 bloody motions during the night, or have a motion consisting of blood only, you should visit the ER at once.

http://www.medicinenet.com/gastroenteritis/article.htm

http://www.mayoclinic.com/health/viral-gastroenteritis/DS00085/DSECTION=1

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