Hello
You didn't mention for which disease , this medicine was advised .
Anyway
allopurinol is advised in HYPERURICAEMIA associated with gout, , recurrent uric acid stone formation,
renal calculi etc .
As these symptoms , you mentioned in the query may be due to disease .
However , the side effects of allopurinol are:
Fever 7
chills,
drowsiness, headache ,
metallic taste , loss of appetite .
Onset of actions , wtihin 24-48 hours , full effects ;several weeks .
So in my opinion take this drug and take after meal ,because maximum dose is 900 mg in divided doses , while this dose is only 300 mg .
It will take few weeks for adjustment .
Alternatively ,you can take some appetizer , after consultation with your physician.
Good luck.