Doxycycline can be recommended by your doctor if you have been diagnosed with any of the following health conditions: respiratory tract infections, urinary tract infections, infections of the genital area, as well as Lyme disease, pneumonia and acne. It's important that you take all the amount of doxycycline that you have been prescribed, as improved symptoms may not mean that the infection has been treated completely and you may suffer a relapse. Doxycycline is not usually prescribed for children younger than 8, but your health care provider may decide otherwise after considering all the risks and benefits of such treatment. This drug can make your skin more sensitive to sunlight. You should do your best to avoid sun exposure and for that purpose wear protective clothing and apply sunscreen with SPF of minimum 15.