Cause of eosinophilia
may be idiopathic ,allergic, hay fever
,parasitic, an some neoplastic disorder
.Treatment of eosinophilia is aimed at cause of eosinophilia.
As you have mentioned you have pain in sole your eosinophilia may be due to parasitic infection
Stool examination may be reqd to rule out parasitic infection .
If it is due to parasitic infection it can be treated by antiworm medicines.