 Preventive therapy in healthy people who have had recent tick bites is not recommended and may only delay the onset of disease.Doxycycline (a tetracycline) is the drug of choice for patients with Rocky Mountain spotted fever, being one of the only instances doxycycline is used in children.Treatment typically consists of 100 milligrams every 12 hours, or for children under at 4 mg/kg of body weight per day in two divided doses.