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Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 7-,*,Copyright 2002, 1998, Elsevier Science (USA). All rights reserved.,Central Nervous System Depressants,1,CNS Depressants,Sedatives,Drugs that have an inhibitory effect on the CNS to the degree that they reduce:,Nervousness,Excitability,Irritability,without causing sleep,2,CNS Depressants,Hypnotics,Calm or soothe the CNS to the point that they cause sleep,3,CNS Depressants,Sedative-Hypnoticsdose dependent:,At low doses, calm or soothe the CNS without inducing sleep,At high doses, calm or soothe the CNS,to the point of causing sleep,4,Sedative-Hypnotics: Barbiturates,First introduced in 1903, standard agents for insomnia and sedation,Habit-forming,Only a handful commonly used today due in part to the safety and efficacy of: BENZODIAZEPINES,5,Sedative-Hypnotics: Barbiturates,Four categories:,Ultrashort,mephobexital, thiamylal, thiopental,Short,pentobarbital, secobarbital,Intermediate,aprobarbital, butabarbital,Long,phenobarbital,6,Sedative-Hypnotics: Barbiturates,Barbiturates have a very narrow therapeutic index.,Therapeutic Index,Dosage range within which the drug is effective but above which is rapidly toxic.,7,Sedative-Hypnotics: Barbiturates,Mechanism of Action,Site of action:,Brain stem (reticular formation),Cerebral cortex,By inhibiting GABA, nerve impulses traveling in the cerebral cortex are also inhibited.,8,Sedative-Hypnotics: Barbiturates,Drug Effects,Low doses:Sedative effects,High doses:Hypnotic effects(also lowers respiratory rate),Notorious enzyme inducers,9,Sedative-Hypnotics: Barbiturates,Therapeutic Uses,Hypnotics,Sedatives,Anticonvulsants,Surgical procedures,10,Sedative-Hypnotics: Barbiturates,Side Effects,Body SystemEffects,CNSDrowsiness, lethargy, vertigomental depression, coma,RespiratoryRespiratory depression, apnea, bronchospasms, cough,11,Sedative-Hypnotics: Barbiturates,Side Effects,Body SystemEffects,GINausea, vomiting, diarrhea,OtherAgranulocytosis, vasodilation, hypotension, Stevens-Johnson syndrome,12,Sedative-Hypnotics: Barbiturates,Toxicology,Overdose frequently leads to respiratory depression, and subsequently, respiratory arrest.,Can be therapeutic:,Anesthesia induction,Uncontrollable seizures: “phenobarbital coma”,13,Sedative-Hypnotics: Barbiturates,Drug Interactions,Additive effects:,ETOH, antihistamines, benzodiazepines, narcotics, tranquilizers,Inhibited metabolism:,MAOIs will prolong effects of barbiturates,Increased metabolism:,Reduces anticoagulant response, leading to possible clot formation,14,CNS Depressants: Benzodiazepines,Most frequently prescribed sedative-hypnotics,Most commonly prescribed drug classes,Favorable side effects,Efficacy,Safety,15,CNS Depressants: Benzodiazepines,Classified as either:,Sedative-hypnotic or Anxiolytic,(Medication that relieves anxiety),16,CNS Depressants: Benzodiazepines,Sedative-Hypnotic Type,Long-Acting:,flurazepam (Dalmane), quazepam (Doral),Short-Acting:,estazolam (Prosom), temazepam (Restoril),triazolam (Halcion),17,CNS Depressants: Benzodiazepines,Anxiolytic Type,alprazolam (Xanax),chloridiazepoxide (Librium),diazepam (Valium),lorazepam (Ativan),midazolam (Versed),zolpidem (Ambien) and zaleplon (Sonata),(nonbenzodiazepine hypnotic agents, share characteristics),18,CNS Depressants: Benzodiazepines,Mechanism of Action,Depress CNS activity,Affect hypothalamic, thalamic, and limbic systems of the brain,Benzodiazepine receptors,19,CNS Depressants: Benzodiazepines,Drug Effects,Calming effect on the CNS,Useful in controlling agitation and anxiety,20,CNS Depressants: Benzodiazepines,Therapeutic Uses,Sedation,Sleep induction,Skeletal muscle relaxation,Anxiety relief,Treatment of alcohol withdrawal,Agitation,Depression,Epilepsy,Balanced anesthesia,21,CNS Depressants: Benzodiazepines,Side Effects,Mild and infrequent,HeadacheDrowsinessDizzinessVertigoLethargyParadoxical excitement (nervousness) “Hangover effect”,22,CNS Depressants: Nursing Implications,Before beginning therapy, perform a thorough history regarding allergies, use of other medications,health history, and medical history.,Obtain baseline vital signs and I & O, including supine and erect BPs.,Assess for potential disorders or conditions that may be contraindications, and for potential drug interactions.,23,CNS Depressants: Nursing Implications,Give 15 to 30 minutes before bedtime for maximum effectiveness in inducing sleep.,Most benzodiazepines (except flurazepam) cause REM rebound and a tired feeling the next day; use with caution in the elderly.,Patients should be instructed to avoid alcohol and other CNS depressants.,24,CNS Depressants: Nursing Implications,Check with physician before taking any other medications, including OTC medications.,It may take 2 to 3 weeks to notice improved sleep when taking barbiturates.,Abruptly stopping these medications, especially barbiturates, may cause rebound insomnia.,25,CNS Depressants: Nursing Implications,Safety is important,Keep side rails up,Do not permit smoking,Assist patient with ambulation (especially the elderly),Keep call light within reach,Monitor for side effects,26,CNS Depressants: Nursing Implications,Monitor for therapeutic effects,Increased ability to sleep at night,Fewer awakenings,Shorter sleep induction time,Few side effects, such as hangover effects,Improved sense of well-being because of improved sleep,27,
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