The proper usage of nasal sprays is important because improper use can lead to unnecessary complications and, more importantly, make you think that the medicine is ineffective when it really may work for you.
The recommendation is based on anatomy. See below:
As you can see, the eustachian tube opening is straight back along the floor of the nose. The nose is also 8 cm in length from front-to-back. Therefore, it is very important to spray directly back rather than upwards to get the medicine into your nose to treat sinus issues and/or eustachian tube dysfunction.
Usage Examples:
The above image is the best example of proper use. Aim straight back after priming the pump to make sure you spray the full dose. Gently inhale as you spray. Try not to blow your nose afterwards so you don’t lose the medication.