This homemade version of vicks rub can provide relief from congestion,  coughing,  and sore muscles. Eucalyptus oil is the key ingredient for its menthol-like  scent. Peppermint oil provides additional soothing and cooling properties. Camphor has been proven to increase blood flow and ease a cough. As first, it produces a cooling sensation on the skin, but after 10 minutes or so, it switches to a warming sensation.