Echinacea tea is a somewhat controversial treatment for colds and other immune system issues, according to the University of Maryland Medical Center. Though the medical center notes that some research suggests echinacea tea may help colds pass more quickly and decrease the severity of their symptoms, preparations of echinacea can vary so significantly that it's difficult to confirm these benefits. As with any herbal remedy, consult your health-care provider if you're considering making echinacea tea part of your health-care regimen.
It's rare, but some people may have allergic reactions after drinking echinacea tea, according to the University of Maryland Medical Center. People who have asthma or allergies, especially people who are allergic to plants in the daisy family, may be especially prone to allergic reactions to echinacea tea. Allergic reactions to echinacea range from fairly mild skin rashes to life-threatening conditions like anaphylaxis, so if you suspect you're having an allergic reaction to using echinacea, seek medical attention immediately.
Immune System Effects
Echinacea tea may stimulate the immune system and interfere with the effects of medications used to suppress overactive immune systems, so people who have progressive systemic or autoimmune disorders -- including tuberculosis, connective tissue disorders and lupus -- shouldn't drink echinacea tea, according to the Herb Research Foundation. Long-term echinacea use may lower your white blood cell count, according to Medline Plus, an online health information resource maintained by the U.S. National Library of Medicine and the National Institutes of Health.
Other Side Effects
As long as you're not exceeding the recommended dosage of echinacea -- 1 to 2 grams of dried echinacea root made into a tea per day, according to the University of Maryland Medical Center -- your risk for side effects is low. Mild side effects can include headaches, stomach discomfort, drowsiness, muscle aches and dizziness, according to Medline Plus. Rarely, echinacea can cause heart, liver or kidney problems.
Possible Drug Interactions
You may experience serious reactions if you take echinacea while taking other medications, according to Medline Plus. Taking echinacea with caffeine will slow down the rate at which caffeine is broken down, which may cause you to experience jitteriness, rapid heart rate and headache. Taking echinacea may also increase the side effects or decrease the effectiveness of certain medications including anti-psychotic drugs, immune-boosting drugs, muscle relaxants, immunosuppresants and blood pressure medications.