Brief Answer:
she needs thorough check-up and a few investigations to clarify further..

Detailed Answer:
Hello XXXXXXX Welcome to HealthcareMagic,
I've gone through your query and understand your concern for your sister,

Well as per your description, it seems like an infective source only (after playing the holi festival)..mostly , it can be due to some water born infection(viral/bacterial)..

Crocin advance and Combiflam both are containing Paracetamol in combination, just give her round the clock plain tab. Paracetamol (650mg) three times daily (eg. Crocin650/Calpol/Dolo etc.) after some food..this will help with the fever and body ache..You haven't mentioned her age here, however i'm assuming she's an adult person only(correct me if otherwise)..

Let her take plenty of rest, plenty of XXXXXXX warm liquids(soups, broths, bournvita etc.), along with well hydration by drinking a lot of water..

Is there any other symptoms apart from the fever/cold/shivering/weakness ?

Any sneezing/runny nose/difficulty swallowing/headache/sore throat/pain in any ear ?

Any cough ? If yes, then is it dry or productive(color of the sputum) ?

Any loose motion/pain abdomen/burning micturition ?

Any other problems ?

Yes, antibiotics may also be required if fever doesn't subside within another day..I'd suggest a few relevant investigations also along with a prompt visit to a physician for a clinical check-up in this regard..

Please let me know all these necessary details, so that I can guide you further..

Take Care
Kind Regards

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