Dependency and Rebound. The major hazard with nasal-delivery decongestants, particularly long-acting forms is a cycle of dependency and rebound effects. The 12-hour brands pose a particular risk for this effect. This effect works in the following way:
- With prolonged use (more than three to five days), nasal decongestants lose effectiveness and even cause swelling in the nasal passages.
- Individuals then become dependent on them.
The patient then increases the frequency of their dose. The congestion worsens and the patient responds with even more frequent doses, in some cases to as often as every hour.
About 1985 it was noted that the number and severity of cases of rhinitis medicamentosum was increasing in proportion to the use of benzalkonium, an antibacterial preservative found in most on the shelf prepared saline nasal spray products. Rhinitis medicamentosum means that the nose gets stuffy and congested after use of nose drops such as oxymetazoline. The more the nose drops are used, the more rebound when the drug wears off, so that the drops become almost addicting and hard to stop. The nose is stuffier after use.>
Then it was discovered that you could get rhinitis medicamentosum just form the Benzalkonium alone, as well as saline with Benzalkonium. So, it wasn't the nasal medication that was responsible, but the Benzalkonium.
When you are allergic or with an infection, the chemicals can be more irritating than when you are "normal".
Recent articles
on the negative effects of Benzalkonium include:
Berg: Mucosa exposed to benzalkonium chloride
showed squamus cell metaplasia ( the normal cells changed
to undesirable cells). Benzalkonium chloride appears to
be potentially toxic to the mucosa.
Steinsvag: benzalkonium chloride has toxic effects on human respiratory mucosa and human neutrophils. It destroyed mucosa and inhibited human neutrophil action Benzalkonium chloride induces mucosal swelling, which explains why the presence of this preservative in a decongestant spray aggravates rhinitis medicamentosa. >
Hoffman An irreversible cessation of ciliary movement was observed in ciliary cells exposed to nasal sprays containing Benzalkonium chloride As benzalkonium chloride can cause complete standstill of ciliary beat frequency in vitro in human nasal mucosa, we recommend that this preservative should not be used anymore in topical nasal medications.