Rebound congestion is also known as rhinitis medicamentosa, chemical rhinitis, nasal spray addiction.
Your nasal passages can develop a dependence to these medications rather quickly.
That’s why prescribers and product labels say to limit use to three days.

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How Decongestants Work
A common belief is that congestion is sparked by mucus blocking your nasal passages.
This is only partially true.
The underlying cause of congestion lies in the blood vessels that line your nose.
Certain conditions can cause these vessels to become swollen or constrict.
However, when the blood vessels constrict, there is more space in the airways and your symptoms subside.
They are available both in oral and nasal spray formulations.
Causes of Rebound Congestion
The reasons whyrebound congestionoccurs are complicated and not well understood.
Thus, a vicious cycle is set up.
Treatment
If you are already addicted to a nasal spray, talk to your healthcare provider.
The first week is usually the most difficult and you may experience severe congestion andheadacheswhich then begin to subside.
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Updated November 17, 2015.