It is difficult to tell if this is an infection or an allergy. Both can produce drainage and either can occur a few times a year. In the winter, it is less likely to be an allergy. Usually an infection has other symptoms such as aching and/or fever. These do not occur with an allergy. Since this appears to be a persistent problem, you should talk to your doctor about it. You may want to see an allergist to find out the cause and take appropriate steps to relieve the problem and perhaps prevent it in the future.
If this were an allergy, the most common treatment would be an antihistamine and perhaps a nasal steroid spray. A nasal steroid spray does not provide immediate relief of symptoms. It may need to be used every day for several weeks to months for it to help. To get the most out of a nasal steroid spray use it after doing a nasal wash. A nasal wash helps remove mucus from the nose and sinuses. Please read our Nasal Wash MedFact at http://www.nationaljewish.org/medfacts/nasal.html for more information about this technique. Share this information with your doctor to see if you would benefit from this daily treatment.
Please read our Allergic and Non-Allergic Rhinitis MedFact at http://www.nationaljewish.org/medfacts/allergic_rhinitis.html for more information