Aside from its culinary value, thyme is used in traditional medicine to treat a variety of health conditions. Its main compound, thymol, is attributed with antimicrobial, antifungal, antioxidant and antitussive properties. In fact, thyme tea is considered an excellent remedy for cough associated with bronchitis and upper respiratory tract infections. However, there are a few thyme tea side effects to consider.
According to a study published in the April 2006 issue of "Contact Dermatitis," you should avoid drinking thyme tea if you have a known sensitivity to plants in the mint family of Lamiaceae. The list of members belonging to this family is long, but some common plants include rosemary, basil, catmint, hyssop, oregano and celery. Juan R. Avila, author of “Professional’s Handbook of Complementary and Alternative Medicines,” advises to avoid thyme if you have an allergy to grass. If you experience chest pain, shortness of breath, tightening of the throat, skin rash or swelling of the joints after drinking thyme tea, seek immediate medical attention.
According to authors Joanne Barnes and Mark Blumenthal, high doses of thyme may produce negative side effects. Some of the most commonly reported side effects associated with thyme include heartburn, nausea, vomiting, stomach upset, diarrhea, headache and dizziness. In addition, the volatile oils present in thyme leaves may promote slowed heart rate and rapid breathing in certain individuals.