 <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]  vitamins/dietary supplements may also contain niacin or nicotinamide. These may increase your risk of side effects if taken together. Ask your doctor or pharmacist for more details. This medication may interfere with certain lab tests (including urine or blood catecholamines, copper-based urine glucose tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug. Does Niacin ER interact with other drugs you are taking? Enter your medication into the WebMD interaction checker Check InteractionThe overdose of Niacin Oral: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.  Notes Do not share this medication with others. Lab tests (such as blood lipids, blood sugar, liver function) should be done while you are taking this medication. Keep all medical and lab appointments.  Missed Dose If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take </s>