Hi.
Thanks for your query.
Noted the history about your brother getting high grade fever for 10 days where his mouth and lips got affected, got infected, increased, now ave started with loose motions, headache, muscle pains and stomach pains. Wants to know further.
As per the history you have given, this looks to be
Gastroenteritis with secondary stomatitis.
I would advise him the following in such a situation:
HE needs urgent tests of blood, urine and stool.
Get started on appropriate antibiotics,
metronidazole, probiotics and multivitamins with
folic acid.
Also needed is symptomatic treatment in the form of
Paracetamol, PPI like
Omeprazole so that he gets better.
If the investigations and clinical evaluation is suggestive, get him admitted for some days for proper care.