Thank you for your comments and I shall follow your aqdvise
Is this a long-term problem, or just something that arose recently? It's either a cold or other virus or infection or allergies. In any case, you'd want a decongestant, which can be natural or pharmaceutical, or if allergies try to see what's causing it -- for example, most people have a problem with wheat and dairy because they're common allergens. So is dust. That would require antihistamines, either natural or pharmaceutical, unless you discover what's causing the allergy and rid yourself of it.