I remember this episode of nearly 35 years back. My father, then about 60 years old, started having a terrible cough. It would go on and on , but intermittently. He was unable to sleep peacefully at night. Initial treatment by the Allopathic doctor did not help. Then, we consulted an Ayurvedic physician whose treatment was taken for about a week. But that did not help too. He took some Homoeopathic medicines too but his condition did not improve.
Then one of his friends who was an Opthalmologist suggested that he get his blood tested for possible Eosinophilia. The test revealed a very high Eosinophils count. The medicine was also suggested by the same friend. It was HETRAZAN. A few days of treatment with this medicine quickly restored him to normalcy.