Normal pain medicine, such as acetaminophen and ibuprofen, works by reducing inflammation and by blocking the production of certain chemicals in the brain that cause pain. While these medications can help to relieve a headache, they do not provide immunity to all pain because they only target specific pathways involved in pain sensation. Additionally, different types of pain can have different causes, and a medication that is effective for one type of pain may not be effective for another. Ultimately, the effectiveness of pain medication can vary depending on the individual and the type of pain they are experiencing.