Unilateral nasal obstruction or one-sided stuffed nose is another name for this type of blockage. Allergies, infections such as sinusitis, and even the common cold can result in this. Additionally, other symptoms may include sneezing, a runny nose, and difficulty breathing. To help clear the blockage, you can use over-the-counter decongestants, saline nasal sprays, or a humidifier. If there is no improvement after a few days see an ENT specialist.