While we may find ourselves reaching for over-the-counter pain relievers to counteract the pain of a pulled muscle or a tension headache, chronic pain sufferers experience persistent, debilitating pain. Pain that sticks around for the long-haul, more than six months and sometimes with no end in sight. Headaches, back pain, joint pain (such as arthritis pain) and injuries all may cause chronic pain, but for some people, there is no discernible reason at all [source: WebMD]. And it's estimated that as many as 50 million Americans live with chronic pain [source: Christo].
One of the most common ways to manage chronic pain is with a prescription for opiates.
Prescription opiates are analgesics, strong pain relievers that contain opium or an opium-derivative (natural and man-made opiates are also called opioids). You may recognize some of these drugs: Morphine, codeine and methadone are all opioids, as are the drugs Oxycontin, Vicodin and Percocet. Tramadol (also known as Ultram) is also a narcotic analgesic -- a synthetic opiate agonist -- used to relieve moderate to moderately-severe pain. It works like morphine, blocking how the body perceives and communicates information about pain.
Opioid medicines are proven to be effective for relieving pain, and are commonly prescribed after surgery and to relieve chronic pain. They work by binding to special receptors in our body, enabling them to block how our brain recognizes and interprets pain. But opioids don't come without side effects. Chronic pain sufferers who take opioid medications are at risk for nausea and constipation (two common complaints), dizziness, drowsiness or sedation, euphoria, vomiting, itching (pruritus) and breathing problems, as well as physical dependency and addiction.
What you might not know about opiate analgesics, though, is that with long-term usage, the risk of additional side effects increases, including the possibility of impairing fertility. Why may long-term usage of opioids make it difficult for some people to become pregnant? Opioid receptors and something called the HPG axis. We'll talk about them both, next.