1. Introduction Nasal decongestant sprays are among the most common medications used to treat nasal obstruction resulting from colds or allergies. However, these drugs are designed for short-term use only (not exceeding 3 to 5 days). Exceeding this period leads to severe disturbances in the nasal mucosal lining, effectively transforming the treatment into a cause of disease. 2. Physiological Mechanism of Action These sprays (such as Oxymetazoline and Xylometazoline) work by stimulating "Alpha-Adrenergic" receptors in the smooth muscles surrounding the blood vessels within the nose. This stimulation leads to vasoconstriction, which reduces blood flow and tissue swelling, thereby opening the airways. 3. Rebound Congestion Phenomenon When these sprays are used for a prolonged period, a condition known medically as "Rhinitis Medicamentosa" occurs. The mechanism of this condition is summarized as follows: Loss of Sensitivity: Blood vessel receptors begin to lose their sensitivity to the drug. Compensatory Congestion: Once the effect of the medication wears off, blood vessels dilate more significantly than they were before treatment as a compensatory reaction, causing more severe obstruction. The Vicious Cycle: The patient is forced to increase the dose or frequency of use to achieve the same sense of relief, leading to a physiological "addiction" to the product. 4. Long-Term Risks and Damages Chronic use of these substances leads to structural and functional damage, including: Mucosal Atrophy: Continuous reduction in blood flow resulting from permanent constriction may lead to the death of the cells lining the nose. Ciliary Dysfunction: The cilia responsible for clearing the nose of germs and dust lose their ability to move, increasing the chances of chronic sinusitis. Nasal Dryness and Bleeding (Epistaxis): Blood vessels become extremely fragile, and the protective mucosal layer dries out, leading to bleeding at the slightest pressure or when blowing the nose. 5. Safe Alternatives and Treatment Protocol To avoid these risks, modern medical recommendations (which align with Al-Mustaqbal University’s vision of promoting good health awareness - SDG3) advise the following: Saline Solutions: Using high-concentration (Hypertonic) saline sprays to naturally draw fluids out of swollen tissues without chemical impact. Nasal Steroid Sprays: For chronic allergies, these sprays are considered safer for long-term use under medical supervision as they treat inflammation directly without causing rebound congestion. Environmental Humidification: Using humidifiers to reduce nasal dryness, which triggers the urge for frequent nose-blowing. 6. Conclusion The key to successful treatment of nasal congestion lies in addressing the underlying cause (inflammation or allergy) rather than merely masking the symptom by constricting blood vessels. Awareness of the permitted duration of use is the first line of defense in protecting the integrity of the upper respiratory system. Al-Mustaqbal UniversityThe First University in Iraq.