Otrivin nasal spray, active ingredient Xylometazoline HCl is used as a decongestant and should be used for that purpose. Overuse of any pharmaceutical can have its side effects. (See Otrivin side effects).
and interact with other medications. (See Otrivin interactions).
He could try other methods of de congestion eg. diet, exercise or other formulation which can be used occasionally.

Not safe. Better try Ocean Spray or saline irrigation.

This is a vasoconstrictor nasal spray. Daily usage can lead to a condition rhinitis medicantosa. The nasal mucosa becomes dependent on the spray to relieve congestion. Most patients who use daily have underlying allergy, anatomic obstruction, turbinate hypertrophy. Should see ENT for nasal exam. Can be weaned with prednisone and flonase. This is assuming threes overriding chronic irritants like smoking, dust exposure, other airway contaminants