Hydrogen peroxide is an acid and a bleaching agent. Care should therefore be taken when using hydrogen peroxide to gargle, since it can damage tissues within the mouth if used inappropriately. The 3% hydrogen peroxide (FDA approved for use as mouthwash) is readily available at any pharmacy and is the one which should be used for personal usage pertaining to oral hygiene. The 35% solution can also be diluted to 3% for this purpose.
Firstly, the 3% hydrogen peroxide from the bottle needs to be diluted with water. This is due to the fact that it is an acid and can cause a burning sensation in the mouth if not diluted before usage. For this, a cap full of hydrogen peroxide should be added to a cup full of warm water. This mixture should then be poured into the mouth to gargle. Care should be taken to not swallow any of this mixture. Swishing the mixture around in the mouth should allow for it to come into contact with the gums and teeth thoroughly. The mixture should be used for gargling for approximately 10 minutes, with the head tilted backwards. Gargling should be done by opening the mouth and exhaling out of the throat. Swallowing can be prevented by continuing to exhale with the mouth closed when lowering the head to spit out all of the liquid into the sink at the end.
Gargling regularly with hydrogen peroxide can have a number of benefits. Since it is a bleaching agent, hydrogen peroxide helps whiten teeth over time. Most whitening products comprise of hydrogen peroxide as the whitening agent. Dentists also suggest gargling with hydrogen peroxide for treating bad breath (halitosis).This is because most cases of bad breath are caused by germs and bacteria within the mouth which give off a foul odor. Peroxide can kill these germs and bacteria and is particularly effective since it can rinse areas that can not be reached with a tooth brush. Similarly, in the event of a sore throat, it can be used to kill the bacteria responsible to provide relief from the pain.
The overuse of hydrogen peroxide runs with it the risk of damage to the enamel of the teeth. There can also be adverse effects from extended usage of hydrogen peroxide, which can similarly lead to the softening of tooth surfaces and cause damage to cells. Overuse should therefore be avoided and any long-term usage should be undertaken in consultation with a dentist.