Doxycycline is a synthetic derivative of tetracycline and is used as an effective agent in the treatment of acne. It is known to be especially useful in treating inflammatory acne. Doxycycline can make the skin excessively sensitive to the sun and hence it becomes imperative to wear sunscreen while using this treatment. Doxycycline is chemically an antibiotic. Antibiotics are useful in treating acne as they prevent bacterial growth in the hair follicles and reduce the production of some irritating chemical compounds by the white blood cells. They also reduce the free fatty acid concentration in the sebum. For an initial dosage, the ideal recommendation is about 50 to 100 mg two times every day. This medicine should not be taken on an empty stomach as that might lead to nausea. It can greatly increase the sun sensitivity of your skin; therefore it is important that you use a sunscreen with a high SPF to avoid sunburns. It can lead to several side effects like diarrhea, swelling of face, sunburns, infrequent urinating and flaking of the skin.