 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST] uth subsalicylate. Some examples include antacids, didanosine solution, quinapril, vitamins/minerals, dairy products (such as milk, yogurt), and calcium-enriched juice. These products bind with doxycycline, preventing your body from fully absorbing the drug. For the best effect, take this antibiotic at evenly spaced times. To help you remember, take it at the same time each day. Do not skip doses or take more of this medication than prescribed. Tell your doctor if your condition does not improve or if it worsens.The side effects of Doxycycline Monohydrate Oral: Upset stomach, nausea, diarrhea, or mild headache may occur. If any of these effects last or get worse, notify your doctor or pharmacist promptly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: nausea/vomiting that doesn't stop, difficult/painful swallowing, brown/gray tooth discoloration, blue/gray/brown discoloration of the skin/lips/ </s>