Food poisoning usually starts with feeling sick and really bad stomach cramps, with many going on to vomit or have diarrhea, and some escalating to stooling and vomiting. The most common causes of food poisoning are bacteria such as salmonella and e-coli.

The symptoms you are experiencing can go a long way in telling what caused it in the first place.

If the food poisoning is vomiting dominant, then it is most likely a staphylococcus infection, and the cause is most likely ingestion of preformed toxins. The symptoms normally start 6 hours after the ingestion and can last for 2 or 3 days. The second most common cause is the Norovirus (which is mainly seen in children).

If the main symptom is watery diarrhea, the most common organism will be clostridium perfringens. This organism is notorious for having so many toxins it has at least 12 known toxins which can cause: Gas gangrene, hemolysis, shock syndrome, and of course food poisoning. Another common cause are Enteric viruses, they are however significantly milder and self-limiting.

If the main symptom is bloody diarrhea, the most likely symptom is Salmonella or Shigella. Another common cause of this symptom is Campylobacter Jejuni, which sometimes escalate to rheumatoid arthritis and Guillain Barre Syndrome. The least common cause of bloody diarrhea is e-coli. You should never give antibiotics for a bloody diarrhea or else you are very sure it is not e-coli, as giving antibiotics to an e-coli infection can increase the likelihood of developing Hemolytic Uremic Syndrome (HUS).

The best things to do are:
Try to rest until you feel better, and it is best to stay at home for 2 days after you’ve stopped vomiting or having diarrhea too as you’re likely to still be infectious.
Drink plenty of fluids: If you are struggling to keep any fluids down you are at risk of becoming dehydrated so it is probably best to speak to a doctor if that is the case.
You can start to eat food when you are feeling up to it: There is nothing specific that you must or must not eat, but you might find foods like rice more comfortable at first.
If you notice blood in your vomit or poo, have severe tummy pains, a high fever, or are struggling to eat or drink and feel that things are just getting worse, it is a good idea to speak to a doctor as soon as possible.