The homeopathic mixture oscillococcinum is very popular in Europe, where it originated, and has gained increasing popularity in the U.S. Studies have shown that oscillococcinum may reduce the duration of the flu and the severity of some symptoms, but there is no evidence that it prevents the flu.
Although echinacea has been touted to prevent or fight a cold, recent studies are conflicting as to whether it is beneficial for a cold or the flu. Studies have been done to examine whether echinacea can prevent, reduce the severity, and decrease the duration of illness. Unfortunately, none of these studies have shown a positive benefit. One criticism of the studies is that there are differing opinions regarding the best echinacea species, plant part, active component, and the dose.
If you want to try echinacea supplements, pick a brand that uses the stems, leaves, and flowers of the Echinacea purpurea plant rather than the root. Don't take echinacea for more than eight weeks -- research suggests that using it for a long period of time may damage the immune system. People who are allergic to ragweed should not take echinacea.
Some research shows elderberry extracts might help reduce flu symptoms when given within the first 24 to 48 hours of symptoms. There are no known side effects of elderberry extract supplements when taken for up to five days. Ingesting the elderberry plant itself should be avoided, as it can cause nausea, vomiting, and diarrhea.
Other herbal remedies that may help when you have flu include:
- Lozenges containing licorice and slippery elm (may help ease sore throats and coughs from post-nasal drip)
- Ginger tea (for nausea)
One word of warning: Evidence on the effectiveness of most herbal supplements is mixed. The CDC has concluded that at this time there is no scientific evidence that any of these remedies are effective against the flu.
Also, potency varies widely from product to product. That makes it hard to know if an herb really works -- or if you’re getting enough of it to make any difference. Experts recommend sticking with those that have been certified by a third party, such as U.S. Pharmacopeia (USP) or NSF International. You should also check with your doctor before trying an herbal remedy, as some interact with other medications. And be sure your doctor knows of everything you are taking -- prescription and over-the-counter medicine and alternative treatments.