Other Pain Relievers
Pain medications can be broadly classified into two categories: prescription and nonprescription. In the latter category are several mild anti-inflammatory drugs (ibuprofen, naproxen), as well as acetaminophen. These are mainly meant for use with short-term, acute pain -- menstrual cramps, tension headaches, minor sprains -- what are known colloquially as "everyday aches and pains." Over-the-counter pain relievers, especially acetaminophen, are also sometimes used to treat chronic pain, such as that seen in arthritis. These drugs also lower fever and are often used for that purpose.
The prescription arsenal against pain is extensive. It also includes some NSAIDs more powerful than their over-the-counter cousins as well as opioid analgesics. And then there are some unconventional analgesics – drugs which were not originally developed as pain-relievers, but which were found to have pain-relieving properties in certain conditions. For example, fibromyalgia pain medications include an antiseizure drug (pregabalin [Lyrica]) and an antidepressant (duloxetine hydrochloride [Cymbalta]).
One major difference between anti-inflammatories and opioid analgesics is that the former have a "ceiling effect" -- that is, continuous dose escalation does not provide concomitant escalation in pain relief. One reason opioids are so useful in the treatment of chronic pain is that as tolerance to a dose develops, the dose can be raised. In fact, there is no limit to how high opioid dosing can go -– keeping in mind that higher doses can be associated with unpleasant and/or even dangerous side effects.