Welcome to HCM,
Your father is having multiple medical problems Diabetes,Hypertension
,Ischemic Heart disease
and Epilepsy due to which is taking poly therapy and he has developed some kind of allergy that is Urtacaria.
The burning sensation could be due to associated peripheral Neuropathy
, please take treatment as advised by dermatologist
as it could be due to allergy also and if any drug is culprit it should be stopped.
The Eptoin dose 100 mg Three times a day is not high dose please continue to take all medicine .