Depends on the kind of sickness you have. Peppermint is good for upset stomach. So is ginger, both in teas. You can also use 2peppermint oil drops in tall glass of water. Just sip it until your stomach calms down.
For a really stuffed nose, boil some water and inhale the steam. You can add eucalyptus oil to the water AFTER taking it off the stove. Put the hot water in front of you at a table and cover your head with a loose towel. If your nose is really stuffed, you can slice an onion and sniff it. It will make it run, and you will get it out of your system.
Without knowing more, this is all I can suggest. Garlic supplement will boost your immunity system. I take 1000 mg per day along with a vitamin/mineral supplement, and it keeps me from getting all that stuff that goes around. Echaneacea (purple cone flower) will boost immunity too. But you use that when the flu season comes, or when something is going around, as it helps prevent you getting sick.
Hope this helps. It does me. Blessed Be...