While nasal breathing is recommended for meditation, a stuffy nose can interfere with it. The condition can have various causes including allergies and the common cold.
Nonprescription decongestants like oxymetazoline restrict blood flow in nasal structures, reducing their volume which eases airflow. But overuse of vasoconstrictive decongestants can lead to dependence, a condition called rhinitis medicamentosa or rebound congestion, where more and more of the product is required to restore normal breathing.
Beating decongestant dependence can require special treatment. Use of oxymetazoline should be limited to avoid this condition.
Non-addictive alternatives include corticosteroids like Nasacort (triamcinolone), the newer nonsteroid antihistamine Astepro (azelastine), and nasal lavage (washing) which clears the nasal passages of pollen and debris.
Nasal lavage requires boiled water or special preparations such as those from NeilMed, because organisms in ordinary water can make it unsafe. Saline sprays can also help. Be careful to choose only saline sprays without preservatives, as these have been linked to undesirable side effects.
Nasal dilators come in external and internal forms. External strips called Breathe Right attach to the outside of the nose with a skin adhesive. These pull outward on the nostrils to open them. The adhesive can lead to plugged pores, however, and the strips can easily become detached from the nose.
Internal dilators like the Mute and Turbine or the Hale are flexible inserts that widen the nasal passages from inside.
A simple pressure technique can be enormously effective. Yoga practitioners apply a support stick or danda under the arm to open a closed nostril.
No special stick is necessary, however. Use your fist or a small ball such as a tennis ball to squeeze the underarm on the side of the body opposite from the closed nostril. For example, if the left nostril is closed, squeeze the left fist under the right arm. You can also press this area over the back of a tall chair. Tighten the upper arm against the object.
This procedure can often open the nostril in a few moments. Try at different times of day and night, and different pressures to learn how it works for you. See the video A bottle under the armpit could clear stuffed sinuses.
Also check Dr. Steven Park's video 7 Insanely Simple Ways to Unblock Your Stuffy Nose.