Transcript Chapter 19
Chapter 19 Analgesics, Sedatives, and Hypnotics Copyright © 2015 Cengage Learning® 1 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® 2 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® 3 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® 4 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® 5 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® 6 Analgesics (cont’d.) • Nonopioid analgesics – Many available without prescription as overthe-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® 7 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® 8 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® 9 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® 10 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® 11 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® 12 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® 13 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 longterm use and respiratory depression (when taken with alcohol) can be potentially fatal Copyright © 2015 Cengage Learning® 14 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 Copyright © 2015 Cengage Learning® 15