These are great questions! I did some research because I know how they work but needed help to put it into words that make sense. Welcome to the world of fibro fog...lol
Anyway, yes the pain is very real. Fibromyalgia is an amplification of pain signals to the brain. All the research to date has not definitively come up with a cause or specific mechanism by which fibromyalgia works but they keep trying. But this all boils down to the fact that we feel pain when we shouldn't. And if we have a small insult to the body, a small amount of pain is amplified into a huge amount of pain. That's why some people can't even have someone touch their skin or wear certain articles of clothing without excruciating pain.
I know it's so very frustrating. Even people who have accepted and lived with fibro for many years have times when they doubt their sanity or the existence of fibromyalgia. But believe me and the others here..it is VERY real.
On how the pain medicines work...below are some tidbits I found around the internet that explain opioid and non-opioid pain relievers. I hope this helps answer your questions.
Non-Opioid pain medications:
Non-opioid analgesics work by inhibiting an enzyme known as cyclooxygenase (COX). COX is a catalyst for the conversion of a fatty acid contained in cell walls—arachidonic acid—to substances known as prostaglandins.
Prostaglandins serve a number of protective functions in the body, but they can also produce pain, inflammation and fever. They cause pain and inflammation after cell injury by a number of mechanisms, primarily at the site of the injury in the peripheral nervous system, that is, nerves outside the brain and spinal cord, but also in the central nervous system. They elevate body temperature by affecting the heat regulating center of a region of the brain known as the hypothalamus.
By blocking COX and, therefore, the subsequent production of prostaglandins in the central and peripheral nervous systems, non-opioid analgesics reduce both fever and inflammation. Acetaminophen, however, differs from the other non-opioids in that it does not block COX in the peripheral nervous system to an appreciable extent. It appears to reduce pain primarily in the central nervous system by more than one mechanism, possibly in part by inhibiting a form of COX known as COX-3, although this is the subject of much debate.
It is, therefore, considered to be a weak analgesic and does not possess anti-inflammatory properties. What this means to you is that acetaminophen is great for headaches, fever and minor aches and pains, but won’t reduce inflammation due to, say, a muscle sprain.
Opioid Pain medications:
Opioids attach to specific proteins called opioid receptors, which are found in the brain, spinal cord, and gastrointestinal tract. When the drugs attach to certain opioid receptors, they block the transmission of pain messages to the brain. Opioids tend to induce euphoria by affecting the brain regions that mediate pleasure. Users generally report feeling warm, drowsy, and content. Opioids relieve stress and discomfort by creating a relaxed detachment from pain, desires, and activity. Opioids also tend to produce drowsiness, reduce heart rate, cause constipation, cause a widening of blood vessels, and depress coughing and breathing reflexes.
Co-Moderator Fibromyalgia & Chronic Pain Forums
Fibromyalgia, Ulcerative Colitis, Insulin dependent diabetic, PTSD, dermatitis herpetiformus, osteoarthritis and a few other side dishes.
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