So it is not the simple CONSTANT COLD/RUNNY NOSE as you reported in the begining. The nose, the throat, the bronchus, the lungs all are involved.

You further report that he takes tablets for hypertension.

You have to record all the relevant (to health) information at one place.

The piecemeal approach (taking valsartan tablets for hypertension and Homoeopathy for runny nose) will not help, as you know, you have taken him to various doctors for no good.