Hi, Welcome to Health care magic forum.
As you describe it appears to be a chronic disease, with defeciency symptoms. It is better if you mention his age etc.
It appears to be the
tuberculosis,
hepatitis B, etc .
The
cough and headache could be due to
allergy, eosinophelia, uvulitis,
sinusitis, etc.
Anemia is the one which can cause all the above symptoms.
I to my patient with such symptoms prescribe cifixime,
paracetamol, difenhydramine hydro chloride,hematinics. till the diagnosis is established.
Take more of green leafy vegetables, pulses, sprouts, and proteine rich foods, and fresh juice of palatable vegetables.
Wishing for a quick and complete recovery. Thank you.