Hello, These tablets are indicated to reduce the development of drug resistant bacteria and maintain the effectiveness of Doxycycline hyalite and other anti-microbial drugs. If Bacteria are suspected to be the cause, then it should use it only to treat infections. It should be taken one-hour prior or two hours after meals. Doxycycline hyalite 100 mg tablets can be used to treat a variety of bacterial infections including acne rosacea. Side effects include difficulty in breathing, swelling of the face, lips, tongue or throat, severe headache, dizziness, blurred vision, flu symptoms, urinating less than usual, watery or bloody diarrhea, pale or yellow skin, dark colored urine, severe pain in upper stomach, loss of appetite, severe skin reaction and many other. It also makes birth control pills less effective. Children should not use Doxycycline because of yellowing or greying of the teeth occurs. You should not take this tablet if you are allergic to doxycycline and liver disease, kidney disease, asthma or sulphanamides. If you are taking vitamins /supplements, then this medication should be taken 2 or 3 hours before or after taking vitamins/supplements, because these products bind with doxycycline, preventing your body from fully absorbing the drug. It may not work if you take it with milk or food, better to be taken orally in an empty stomach. It is better to take with full glass of water. They work best when the amount of medicine in your body is kept at a constant level. Therefore take this drug at evenly spaced intervals. Continue the medication until the full-prescribed amount is finalized even if symptoms disappear after a few days. Stopping the medication too early may allow bacteria to continue to grow. Thank you.