Read on to learn about the common and rare side effects of doxycycline and how to manage them. Doxycycline is a generic prescription drug used to treat certain infections and acne. Learn about side effects of the drug and how to manage them. What are the most common side effects of Doxycycline? The most common side effects are nausea, diarrhea, abdominal pain, and increased sensitivity to sunlight (photosensitivity). Common side effects of doxycycline include stomach upset and sun sensitivity, which typically improve once the medication is stopped. Rare but serious risks include severe diarrhea and dangerous skin reactions. NHS information about the medicine doxycycline, including what it's used for, who can take it, how to take it and side effects. Usually, doxycycline side effects like upset stomach or nausea can go away a few days after stopping the medication. More serious symptoms, like sun sensitivity, can last up to a week after stopping doxycycline. See a healthcare provider if symptoms like diarrhea persist. Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. What are the most common side effects of doxycycline? The most common side effects of doxycycline are listed below. Tell your health care provider if you have any of these side. The most common doxycycline side effects include nausea and vomiting, upset stomach, loss of appetite, mild diarrhea, skin rash or itching, darkened skin color, and vaginal itching or discharge. Learn about the side effects of doxycycline, from common to rare, for consumers and healthcare professionals.