Most people think of nasal spray as something that is meant to be delivered through the nasal passageways when they need a decongestant in order to clear their nose to breathe. In actuality it is a medically generic term that encompasses an overall technical medical delivery system for medicine. This is covered at length in other parts of this site. This information is not appealing to the largest audience as it is a specialized delivery system with specialized characteristics. Such as flu vaccine, pain relief,and for allergies.
Now To An Overview.
The most common type acts as a decongestant . These operate by delivering a fine mist of medicine directly to the congested area. The primary way they work is the medicine immediately restricts the blood flow in the inside of the nasal cavity. This then causes the passages to constrict and hence clear. Most of these decongestant types have active medical ingredients that are a derivative of hydrochloride. But there is a sub category of decongestants that use a natural saline. While the medical spray attempts to treat the symptom of a congested nose, the saline spray attacks the root by attempting to neutralize the cause of the congestion. This could be pollen, dust, or any other cause that finds its way into the nostril.
When you study the way our nostrils capture, filter, and then discharge irritants you will find that the common root is moisture in the nose. Therefore when the saline is added it gives the already inflamed and congested nose the extra needed boost of moisture to remove the irritant through air flow.
As we breathe the air flow goes through the nostril picking up moisture as it flows out and the moisture attaches itself to the pollen or other irritant and discharges it through the exhale. It is common for non medicinal cures to attack a cause whereas most medical cures attack symptoms.
Lesser Known Types

How To Use It
The way you use it is determined by the type you have purchased. For the most part there are two types of delivery systems for the nasal spray. The first is from a pump spray – this pump spray you maneuver the bottle buy squeezing it in some manner and then the spray is released.
Pump Bottles

The proper way to use a pump bottle is to first blow your nose. This eliminates anything that is currently in your nostril and will allow the medicine to get to the nasal cavity interior wall for maximum effectiveness. It is important to remember that you want to have your nostril just clear enough to breathe through before spraying. The reason is that the spray needs to get far into the nasal cavity. If blowing your nose does not clear the cavity enough to slightly breathe through it then you can try standing up and walking around or try laying down on your side with the nostril you want to clear on your top side. These two methods usually cause enough temporary relief to allow you to take the spray.
Compressed Air Bottles
Now that you can breathe even if just a little take the nasal spray pump bottle and test spray it. You want to make certain that the medicine is completely in the spray. You do not want to spray a bunch of air into your nostril without the medicine and think you are doing things correctly. You then position your nose a little forward and down. Close the opposite nostril, squeeze the pump, slowly breathe in. Do this for as many times as is recommended on the bottle. Then do the same for the other nostril.
Now remember you are spraying a mist into your nose. This will cause you to want to immediately blow your nose – read the package directions, but normally you do not want to blow your nose because you may be blowing out the medicine. Each nasal spray is different so consult the instructions for proper reactions to this desire to blow after taking the spray.

Please remember the following!
It is important to wash your nasal spray container. Not through submersion, but by wiping it down. You do not want a pollen spore to attach itself to the spray spout only to have you re-insert it at the next application – causing yourself more troubles. Wipe the spout down periodically to ensure it is clean. If you have any adverse reactions at all – call your doctor. Adverse reactions can be defined as anything that occurs other than what is intended. Therefore if anything odd happens – call your doctor. It is always better safe than sorry. And most certainly if there is any blood, pain, swelling – anything – just call your your doctor and or seek emergency attention immediately! These things are NOT supposed to happen and your health is more important than being embarrassed by asking your doctor a question. Better to ask and seek emergency medical attention than be sorry.