The next time symptoms of a cold appear could be well worth it to reach for elderberry syrup, lozenges or supplements. According to the University of Maryland Medical Center, elderberry, or elder, has been used for centuries to treat various ailments. Elderberry can be applied to the skin to relieve wounds, and it also is effective when taken orally to treat respiratory illnesses like cold and flu. Some evidence suggests that elderberry may help reduce swelling in the mucus membranes and sinuses to help relieve nasal congestion. WebMD says elderberry may help boost the immune system and reduce inflammation to relieve pain throughout the body. Some people also rely on elderberry for allergic rhinitis (hay fever) and as a laxative. Even though elderberry is an all-natural alternative to medicine, its use should be discussed with a doctor to ensure no contraindications.