Doxycycline.

Doxycycline can be prescribed if you have some bacterial infections – such as respiratory tract infections, Lyme disease, infections of skin, genital, and urinary systems, as well as acne. It's very important that you continue taking doxycycline for as long as needed to make sure the infection has been completely treated. If you stop taking doxycycline before the infection has been completely treated, a relapse of infection is possible. If you get diarrhea, vaginal itching, sores or swelling in your rectal or genital area, vomiting, mild nausea, trouble swallowing, sore mouth, stomach upset, or swollen tongue, there is no need to worry – as those are normal side effects of doxycycline that may be experienced when your body is adjusting to the dose. More serious side effects are unlikely but still possible and can include any of the following ones: blurred vision, red skin rash, severe blistering, severe headache, body aches, urinating less than usual, confusion or weakness, loss of appetite, pale or yellowed skin, dizziness, yellowing of the skin or eyes, peeling, flu symptoms, severe pain in your upper stomach, as well as easy bruising or bleeding.