What condition should intranasal decongestants NOT be used for longer than 3 days due to rebound congestion?

Intranasal decongestants are effective in alleviating nasal congestion due to various conditions; however, their use is limited to a short duration—specifically, no more than three consecutive days. This limitation is primarily to prevent a phenomenon known as rhinitis medicamentosa, which refers to rebound congestion resulting from the overuse of these medications.

When intranasal decongestants are used for longer than the recommended period, the nasal mucosa can become desensitized to the medication, leading to increased congestion once the medication is discontinued. This rebound effect can create a cycle where the user feels compelled to continue using the decongestant, worsening their condition.

In contrast, the other conditions mentioned do not have the same risk of rebound congestion associated with extended use of intranasal decongestants. While decongestants can be used for allergic rhinitis, sinusitis, and nasal polyps, the key distinction with rhinitis medicamentosa is the potential for creating a dependency on the medication due to the rebound phenomenon. This makes it the primary condition for which prolonged use of intranasal decongestants is inadvisable.