Copyright © 2015 Cengage Learning® 1 Chapter 19 Analgesics, Sedatives, and Hypnotics

Copyright © 2015 Cengage Learning® 2 Introduction Analgesics, sedatives, and hypnotics –Depress central nervous system (CNS) action to varying degrees –Some drugs can be classified into more than one category, depending on the dosage Analgesics: relieve pain Sedatives: calm, soothe, or produce sedation Hypnotics: produce sleep

Copyright © 2015 Cengage Learning® 3 Introduction (cont’d.) The following slides discuss various analgesics, sedatives, and hypnotics –Refer to the chapter for specific side effects, contraindications, and interactions

Copyright © 2015 Cengage Learning® 4 Analgesics Pain is the most common reason for patients to seek out medical care –Most common types: back, neck, migraine, and facial or jaw pain –Is subjective: can be experienced or perceived only by the individual subject –Can be blocked by endorphins Endogenous analgesics produced within the body as a reaction to severe pain or intense exercise

Copyright © 2015 Cengage Learning® 5 Analgesics (cont’d.) Opioid analgesics –Full or pure agonists, partial agonists, or mixed agonist-antagonists Each bind to specific receptors with varying degrees of action Classified as controlled substances Potential for abuse and psychological dependence Tend to cause tolerance and physiological dependence

Copyright © 2015 Cengage Learning® 6 Analgesics (cont’d.) Tramadol (Ultram) –Centrally acting synthetic analog of codeine with a dual mechanism of action –Produces analgesia by weak inhibition of norepinephrine and serotonin reuptake; is an opioid receptor agonist –Less potential for abuse or respiratory depression (although both may occur) –Currently not classified as a controlled substance on the Federal level

Copyright © 2015 Cengage Learning® 7 Analgesics (cont’d.) Nonopioid analgesics –Many available without prescription as over- the-counter (OTC) medications –Given for relieving mild to moderate pain, fever, and anti-inflammatory conditions –Used as a coanalgesic in severe acute or chronic pain requiring opioids

Copyright © 2015 Cengage Learning® 8 Analgesics (cont’d.) –Salicylates (aspirin) are most commonly used for their analgesic and antipyretic properties, as well as for their anti-inflammatory action –Acetaminophen has analgesic and antipyretic properties, but very little effect on inflammation –Aspirin and acetaminophen are frequently combined with opioids or with other drugs for more effective analgesic action

Copyright © 2015 Cengage Learning® 9 Analgesics (cont’d.) Salicylates and other NSAIDS –Analgesic and anti-inflammatory actions Associated primarily with preventing formation of prostaglandins and subsequent inflammatory response that prostaglandins help to induce Acetaminophen (Tylenol) –Used extensively to treat mild to moderate pain and fever Very little effect on inflammation, but fewer adverse side effects than salicylates

Copyright © 2015 Cengage Learning® 10 Analgesics (cont’d.) Adjuvant analgesics –May enhance analgesic effect with opioids and nonopioids, produce analgesia alone, or reduce side effects of analgesics Tricyclic antidepressants –Treats fibromyalgia and nerve pain associated with herpes, arthritis, diabetes, and cancer, migraine or tension headaches, insomnia, and depression

Copyright © 2015 Cengage Learning® 11 Analgesics (cont’d.) Anticonvulsants (i.e., Neurontin and Tegretol) –Commonly used for management of nerve pain associated with neuralgia, herpes zoster (shingles), and cancer –Implemented when patient describes pain as “sharp,” “shooting,” “shock-like pain,” or “lightning-like”

Copyright © 2015 Cengage Learning® 12 Local Anesthetic Lidocaine patch (Lidoderm) –Approved for management of postherpetic neuralgia –Can provide significant analgesia in other forms of neuropathic pain Diabetic neuropathy and musculoskeletal pain such as osteoarthritis and low back pain –Provides pain relief through a peripheral effect and generally has little, if any, central action

Copyright © 2015 Cengage Learning® 13 Local Anesthetic (cont’d.) Antimigraine agents –Simple analgesics, NSAIDs, and opioid analgesics can be effective, especially if taken at initial sign of migraine Serotonin receptor agonists (SRAs) –Action: serotonin levels decrease, while vasodilation and inflammation of blood vessels in brain increase as migraine symptoms worsen Effective in treating associated nausea and vomiting

Copyright © 2015 Cengage Learning® 14 Sedatives and Hypnotics Medications used to promote sedation in smaller doses –Promote sleep in larger doses Benzodiazepines (BZDs) and nonbenzodiazepines –Less abuse potential –Withdrawal effects are observed after long- term use and respiratory depression (when taken with alcohol) can be potentially fatal

Copyright © 2015 Cengage Learning® 15 Sedatives and Hypnotics (cont’d.) Melatonin receptor agonist –Ramelteon (Rozerem): first FDA-approved prescription medication that acts on melatonin receptor Mimics action of melatonin to trigger sleep onset Dependence and abuse potential are eliminated Not classified as a controlled substance Works quickly, generally inducing sleep in less than one hour