Doxycycline is the treatment of choice for acute Q fever. Antibiotic treatment is most effective when initiated within the first 3 days of illness. A dose of 100 mg of doxycycline taken orally twice daily for 15-21 days is a frequently prescribed therapy. Quinolone antibiotics have demonstrated good in vitro activity against C. burnetii and may be considered by the physician. Therapy should be started again if the disease relapses. Chronic Q fever endocarditis is much more difficult to treat effectively and often requires the use of multiple drugs.