So as long as you can stand the smell you could try placing a plate of chopped onion in your bedroom.
Onion in room overnight.
Take half of a cut onion and put it in a bowl.
There is no scientific evidence to prove it.
Please remember it is dangerous to cut an onion and try to cook it the next day it becomes highly poisonous for even a single night and creates toxic bacteria which may cause adverse stomach infections because of excess bile secretions and even food poisoning.
Simple tips to prevent catching the cold or flu was this page helpful.
Manuel viso onion is also a proven bactericide and can even help to loosen mucus.
There have been many other versions of this story claiming that leaving onions around a room will absorb the flu virus along with bacteria causing other illnesses and will prevent people from becoming sick.
Placing an onion in the room will not treat or prevent you from getting a cold.
Place the bowl in your room to remain there overnight to absorb the harmful toxins in your environment.
There are a variety of onions that work well to increase your health.
It s a fact onions were used in folk medicine long before 1919 but it s just a false belief.
However white onions are encouraged for use.
In the morning the room does stink of onion but it doesn t last.
As trisha wrote you need to use a fresh onion every night that you need to do this.
Sliced onions in a sick room absorb all the germs and prevent contagion there is of course no more scientific basis for the belief that onions absorb all the germs in a room than there is for the belief that onions rid the air of infectious poisons viruses and bacteria can become airborne via droplets of saliva or mucus when people cough.
Placing a raw cut onion in contact with your foot overnight purifies your blood removes toxins and heals your body.
I have always simply put the onion in a plate on the night stand besides the person s head while they are sleeping.