I Lost My Voice Three Years Ago. All The Exams,mri

I lost my voice three years ago. All the exams,mri , and lab tests are negative. I don't have no lumps nor any disorders in my throat,lungs,and chest. Neither the Drs. of ENT, NEUROLOGIST ,GASTROENTEROLOGIST can't find out what happened . It all started with a mild cough and sore throat. After two weeks I got better. My dr. put me on antibiotics (penicillin ) and a common cough medicine . After that I started loosing my voice without any symptoms . Maybe you can give me an idea or recommend me something to try to return my voice. I am 59 years old. I'm epileptic and have high blood pressure. I take Lamictal 100 two times a day and Diovan 160/25. I'm 5 feet 7 inches tall. Hope you can help. Thank you.