Thank you for your question. Common causes of postnasal drip (sensation of mucous stuck in the back of the nose or throat) include:
- Conditions of the nose (e.g sensitive nose or rhinitis, sinusitis)
- Acid reflux to the throat (called laryngopharyngeal reflux)
- Dehydration
In patients I’ve seen with similar history to yours, a one sided nasal congestion or postnasal drip may indicate an active sinus infection (sinusitis).
Since it has been ongoing for several months without relief from nasal steroid spray and antihistamine, and you’ve had previous sinus surgery (sphenoidoyomy), I would suggest consulting an ENT Specialist for evaluation.
Your ENT specialist will be able to perform a nasoendoscopy (scope through the nose) to examine the nasal cavity, previously operated sphenoid sinus and your voice box.
If you do have sinusitis, you will need a course of oral antibiotics, nasal douche (nose wash with salt solutions) in addition to the nasal steroid spray.
Hope this helps.