Should One Of The Medications Be Compromised Due To Ethambutol Allergy?

my father is 80 years old and diagnose with spine TV before 5 months back, akt has started and passing through many other side effect of johoneseas and low sodium , potentium etc. want to know it appear we have allergy with " ethambutol" (one of the akt medicine) , we are continue with other 3 medicine hensapran , oflox and solonex are continue. want to know what we should do , compromise one of the medicine ?