If body temp reach 37.5 .shall i give medicne?

Depends: Technically, we consider a true fever of 38.0 or higher. Assuming you have no kidney or liver disease, tylenol (acetaminophen) or Motrin would be an option for symptom relief. If you're concerned about infection, it really depends on the source such as pneumonia, cold, urinary tract infection, etc. Not all requires antibiotics and if they do require treatment, it would depend what you have. Best to see your doc.