Echinacea may cause minor side effects. These may include an upset stomach, nausea, and dizziness. Serious side effects include allergic reactions such as rash, swelling, and difficulty breathing. It can also make asthma symptoms worse.
DO NOT take echinacea on an empty stomach. Instead, take it with food or with a large glass of water. Apply creams or ointments to wounds that heal slowly as needed. Avoid coffee, tea, cola, energy drinks, or other products that contain caffeine.
Taking echinacea with caffeinated products can increase the side effects of caffeine, such as headache, increased heart rate, and nervousness. Echinacea is generally safe to take, and serious side effects seem rare.