Sedatives and hypnotics.pptx

Done by: Dr. Rawan Al-Gharaibeh Sedatives and hypnotics  Anxiolytic: drug used to depress the central nervous system (CNS); prevents the signs and symptoms of anxiety. Sedatives: reduce nervousness, excitability, and irritability without causing sleep. Hypnotics: cause sleep and have a much mo...

Done by: Dr. Rawan Al-Gharaibeh Sedatives and hypnotics  Anxiolytic: drug used to depress the central nervous system (CNS); prevents the signs and symptoms of anxiety. Sedatives: reduce nervousness, excitability, and irritability without causing sleep. Hypnotics: cause sleep and have a much more potent effect on the CNS than do sedatives.  Many drugs are called sedative-hypnotics because they can act in the body as either a sedative or a hypnotic, depending on dose and patient responsiveness Sedative-hypnotics can be classified chemically into three main groups: Barbiturates Benzodiazepines miscellaneous drugs. 1. Anxiety: It is the unpleasant state of mind chiefly characterized by a sense of dread and fear Anxiety is a normal physiologic emotion. Anxiety may occur as a result of a wide range of medical illness (e.g., cardiovascular or pulmonary disease, hypothyroidisim and hypoglycemia). Persistent anxiety is divided clinically into several distinct disorders, including the following :  Anxiolytic drugs: Benzodiazepines. Buspirone. Beta-blockers. Antideprassants. 1. Benzodiazepines: (Diazepam, lorazepam, midazolam) Mechanism of action and drug effects: All anxiolytic drugs decrease anxiety by reducing overactivity in the CNS. Benzodiazepines seem to exert their effects by depressing activity in the areas of the brain called the brainstem and the limbic system. Benzodiazepines are believed to accomplish this by increasing the action of gamma-aminobutyric acid (GABA) Indications: They are commonly used for: Anxiety relief. Sleep disorders >> it is generally recommended that they be used in short term to avoid dependency Skeletal muscle relaxation Treatment of seizure disorders Amnesia Some benzodiazepines are used in the treatment and prevention of the symptoms of alcohol withdrawal. chlordiazepoxide, clorazepate, diazepam, lorazepam, and oxazepam are useful in the acute treatment of alcohol withdrawal and reduce the risk of withdrawal-related seizures. Contraindications: known drug allergy narrow-angle glaucoma pregnancy. Adverse effects (mild): Headache Drowsiness paradoxical excitement or nervousness dizziness or vertigo cognitive impairment lethargy. can create a significant fall hazard in elderly patient. Toxicity and management of overdose:  Somnolence, confusion, coma, and diminished reflexes  Do not cause hypotension and respiratory depression unless taken with other CNS depressants  Treatment: symptomatic and supportive. Use Flumazenil as an antidote. Drug profiles: Diazepam: Diazepam was the first clinically available benzodiazepine drug. It is available in oral, rectal and injectable forms. It has varied uses, including:  treatment of anxiety procedural sedation and anesthesia adjunct anticonvulsant therapy skeletal muscle relaxation. 2. Buspirone: It is an attempt to produce an anxiolytic drug without adverse effects. It appears to have no sedative action or risk of dependence its only adverse effects appear to be occasional nausea and headache. 3. Antidepressants: - Will be discussed in the next chapter. Insomnia: Insomnia can, however, cause feelings of anxiety, inability to concentrate and general debility. Some reasons may cause failing to sleep include: Anxiety and stress. Depression. Physical illness. Pain. Physiology of sleep: Sleep is defined as a transient, reversible, and periodic state of rest in which there is a decrease in physical activity and consciousness. Sleep research involves study of the patterns of sleep, or what is sometimes referred to as sleep architecture. The architecture of sleep consists of two basic elements that occur cyclically: rapid eye movement (REM) sleep and non-rapid eye movement (non-REM) sleep. Prolonged sedative-hypnotic use may reduce the cumulative amount of REM sleep; this is known as REM interference >> This can result in daytime fatigue. On discontinuance of a sedative-hypnotic drug, REM rebound can occur in which the patient has an abnormally large amount of REM sleep >> often leading to frequent and vivid dreams. 1. Benzodiazepines. Benzodiazepines (BDZ) are classified as either sedatives-hypnotics or anxiolytics depending on their primary usage. However, any of these drugs can function along a continuum as a sedative and/or hypnotic and/or anxiolytic depending on the dosage and patient sensitivity to drug action.. 2. Zaleplon and zolpidem. They function much like benzodiazepines but are chemically distinct from them. Zolpidem: It is a short-acting hypnotic. It’s has a lower incidence of daytime sleepiness compared to benzodiazepines.. 3. Ramelteon: It is the newest prescription hypnotic. This drug is structurally like the hormone melatonin, which is believed to regulate day-night sleep cycles in the body (melatonin agonist) It is used as hypnotic, its lack dependency effect. It potentially has a shorter duration of action than other hypnotics >>> therefore indicated primarily for patients who have difficulty with sleep onset rather than sleep maintenance. Its use is contraindicated in cases of severe liver disease.. 4. Barbiturates: They were first introduced into clinical use in 1903 and were the standard drugs for treating insomnia and producing sedation. They are habit forming and have a low therapeutic index. Mechanism of action and drug effects: They act primarily on the brainstem in an area called the reticular formation. Their sedative and hypnotic effects are dose related, and they act by reducing the nerve impulses traveling to the area of the brain called the cerebral cortex. Their ability to inhibit nerve impulse transmission is in part due to their ability to potentiate the action of inhibitory neurotransmitter GABA. Indications:  Ultra short-acting (thiopental): Anesthesia for short surgical procedures, anesthesia induction, and control of convulsions.  Short-acting (pentobarbital, secobarbital) and intermediate (butabarbital): Sedation/sleep induction and control of convulsive conditions  Long-acting (Phenobarbital): Sleep induction, epileptic seizure prophylaxis Contraindications: known drug allergy significant respiratory difficulties Pregnancy severe kidney or liver disease. Drug interactions: They are enzyme inducers, they stimulate the action of enzymes in the liver for the metabolism of many drugs, and this shortens the duration of action of many drugs. Adverse Effects  CNS: Drowsiness, lethargy, vertigo, mental depression.  Respiratory: Respiratory depression, apnea, bronchospasms, cough.  GI: Nausea, vomiting, diarrhea, constipation  Others: Agranulocytosis, hypotension, Stevens-Johnson syndrome  5. Antihistamines like promethazine.. Nursing implications: Give hypnotics 30 to 60 minutes before bedtime for maximum effectiveness in inducing sleep (depends on drug’s onset) Most benzodiazepines cause REM rebound and a tired feeling the next day; use with caution in the elderly Instruct patients to avoid alcohol and other CNS depressants Check with physician before taking any other medications, including over- the-counter medications  Rebound insomnia may occur for a few nights after a 3- to 4- week regimen has been discontinued Safety is important: Keep side rails up or use bed alarms and keep call light reach. Assist patient with ambulation (especially the elderly)