Summary NURS 251 Pharmacology Module 8

NURS 251 Pharmacology Module 8 Module 8 8.1 : Pain Pain is a basic protective mechanism of the body. The sensation of pain may serve as a warning of imminent danger (fire) or that there is something wrong in the body (cancer). Alternatively, pain can accompany the normal healing process (inflammation). When the intensity and duration of a person’s pain begin to affect their ability to function, analgesics can become very helpful. Analgesics are defined as medications that relieve pain without causing a loss of consciousness. As there are different types of pain, the appropriate pharmacologic therapy may differ from one type of pain to another. Acute pain is sudden in onset and usually subsides when treated. Acute pain often lasts 6 weeks or less in duration. Chronic pain is persistent or recurring and often much more difficult to treat. It is classified as any pain lasting 3-6 months or pain lasting longer than 1 month after healing of an acute injury. Tolerance refers to a state in which the effectiveness of a drug is significantly reduced following its prolonged use. As the body adapts, more of the drug becomes required to achieve the same initial physiological effect. Should the drug be stopped abruptly or smaller dosages given, unpleasant physical and mental symptoms are often observed, a state referred to as withdrawal. Under such conditions, a physical dependence, which is a need to continue taking a drug to avoid the unwanted side-effects of its absence, is said to be established. In order to avoid withdrawal, the continual use of a drug may lead to addiction. Addiction is defined as a chronic neurobiological disease in which genetic, psychosocial, and environmental factors induce changes in the individual’s behavior to compulsively use drugs despite the harm they may cause. For these reasons, the treatment of chronic pain can be especially challenging and should be closely monitored. Most analgesics can be classified as either opioids or non-opioids. Opioid analgesics are synthetic drugs that bind to the opiate receptors in the brain and relieve pain. Opioid analgesics are strong painkillers and are capable of alleviating pain of any origin. They are known to cause tolerance and physical dependence and therefore should be reserved for moderate to severe pain. Nonopioid analgesics include painkillers that do not work on opioid receptors, the primary example being Non-Steroidal Anti-inflammatory Medications (NSAIDs) as introduced in Module 2. NSAIDs are a large, chemically diverse group of drugs that are analgesics and also possess anti-inflammatory and antipyretic activity. Neuropathic pain is a unique classification of pain and is defined as pain resulting from a damaged nervous system or damaged nerve cells. Due to its unique origin, neuropathic pain does not typically respond to traditional pain medications including opioids and NSAIDs. It can be extremely difficult to manage and is generally treated with a variety of medications from different classes that have shown to have some effect on neuropathic pain. Examples include antiseizure medications, antidepressants, and new classes that have been developed to treat neuropathic pain. Fibromyalgia is one of the most common neuropathic pain conditions and is defined as a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, and sleep, memory and mood issues. Researchers believe that fibromyalgia amplifies painful sensations by affecting the way your brain processes pain signals.