Since your nasal congestion has been long-term and is not improving with medications like Otrivin, and your CT shows a mild deviated septum, it is important to see an ENT specialist. Long-term use of nasal decongestant drops can worsen congestion, so they should be stopped gradually under medical guidance.

Otrivin Oxy Fast Relief Adult Nasal Spray can be used for temporary relief of nasal congestion caused by allergies, cold, sinusitis, or hay fever. It contains Oxymetazoline hydrochloride, which narrows the blood vessels in the nasal passages to reduce swelling and make breathing easier. However, it should be used only for 3–5 days, as prolonged use may cause rebound congestion. People with asthma, high blood pressure, heart disease, or thyroid problems should consult a doctor before using it, and it is not meant for the treatment of asthma itself.

Having a blocked nose and sneezing mainly while sleeping is commonly due to allergic rhinitis. Triggers like dust mites in bedding, pillows, blankets, room dust, cold air, or a fan/AC can irritate the nose at night. Lying down also increases nasal congestion. Keeping the room dust-free, washing bedding regularly in hot water, and using a saline nasal spray can help. If it happens often, a doctor may suggest anti-allergy treatment.

Sneezing when moving between air-conditioned and non-air-conditioned rooms is often due to temperature changes irritating your nasal passages, and smoking can worsen nasal irritation and allergies. Try to avoid sudden temperature changes, keep rooms well-ventilated, and reduce or quit smoking, as even a small amount can trigger symptoms. Using a saline nasal spray before moving between rooms may help, and if sneezing continues or worsens, see a doctor for allergy evaluation.

If allergic rhinitis is severe and not improving with medication, it is important to see an allergy specialist. They may suggest allergy testing to identify triggers and adjust treatment, which could include stronger or different medications, nasal steroid sprays, or allergy shots (immunotherapy). Along with medicine, avoiding known allergens, keeping your home clean, and using air filters can help reduce symptoms.

To manage continuous allergies, cold, and sneezing, first try to identify and avoid triggers like dust, pollen, pets, or certain foods. Keep your home and bedding clean, use air filters, and wash your hands and face regularly. Saline nasal sprays can help clear the nose, and doctor-prescribed antihistamines or nasal steroid sprays can reduce symptoms. If it persists, an allergy specialist can do testing and suggest long-term treatment to control your allergies effectively.