If you have a cold and want to naturally cure it, try some aromatherapy oils such as Tea Tree Oil, Eucalyptus Oil, or Lavender Oil. Either place some of the oil in a large bowl and pour water in it and then inhale the smell, or add a few drops of oil on a handkerchief and breath it in. This will help clear your nose blockage and help with a heavy headache too. Garlic is also a natural medicine to help keep away germs and colds. Try eating fresh garlic with pasta, it's an effective way to reduce a cold.

Fresh water is also helpful for a cold and hot herbal teas such as Peppermint are good too.

reduce a cold という表現は初めて見ました。風邪の症状とか程度が軽くなるという意味なのでしょうか？