1 The range of doses for all forms of doxycycline is 100 to 200 mg a day, with a maximum daily dose of 600 mg. 2  When taking doxycycline for the prevention of malaria, you should start taking the drug 1 to 2 days before traveling to an area with malaria.oxycycline is also used to treat Lyme disease, anthrax, and acne. It may also be used by your dentist to treat periodontitis (inflammation within the mouth). This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.