Hello and Welcome to ‘Ask A Doctor’ service.
I have reviewed your query and here is my advice.
There are other pathogens that can cause these symptoms. These are many viruses which can cause symptoms in various parts of the body simultaneously such as head, throat, and stomach.
I would suggest your son to rest, treat his headache, throat and stomach pain with
Acetaminophen and Lozenges drugs, and offer him fluids(they can be cool to soothe his throat) every 2 to 3 hours, if he is not
vomiting.
If he vomits, then wait for 2 to 3 hours more before letting him have fluids. Another way to have him feel better if he still has the
fever and throwing up would be to place him in the tub of luke-warm water and sponge him down for five to ten minutes.
If this is only a viral illness, then it ought to run its course in 3 or 4 days. You will identify if he is in better health when his appetite returns.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Arnold Zedd