ppt chapter 15-1

Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Chapter 15

Drugs Relieving Anxiety and Promoting Sleep


Question

• What system in the brain is responsible for emotion?

– A. Amygdala system

– B. Reticular system

– C. Limbic system

– D. Ventricular system


Answer

• C. Limbic system

• Rationale: The limbic system in the brain is known to be primarily responsible for emotions.


Emotions and Neurotransmitters

• The limbic system in the brain is known to be primarily responsible for emotions.

• The amygdala receives incoming sensory signals and then communicates with the frontal lobes of the brain.

• The amygdala can signal the brain that a threat is present and set off a fear response or anxiety.

• Another part of the brain, the hippocampus, is responsible for processing threatening or traumatic stimuli.

• The brain sends its messages to the body by way of the nervous system.


GABA Cell Receptors


Sleep

• Sleep is a time of bodily rest, although the brain remains active.

• There are two phases:

– No rapid eye movements (NREM)

– Rapid eye movements (REM)


Sleep (cont.)

• NREM stages of sleep are further divided into

– Stage 1—light sleep; muscles relax; brain waves are irregular and rapid.

– Stage 2—brain waves are larger than in stage 1, with bursts of electrical activity.

– Stages 3 and 4—deep sleep, with even larger, slower brain waves called delta waves.


Sleep (cont.)

• A number of physiologic changes occur during sleep.

• The amount of sleep needed by a person varies throughout the life span, with infants requiring the most sleep and adults requiring the least.


Anxiety • Anxiety is a feeling of unease that something bad or

undesirable may happen.

• Some anxiety is normal; it is a protective mechanism.

• Anxiety becomes pathologic when it is severe and chronic and interferes with a person’s ability to function in normal life.

• Anxiety disorders can become progressively worse if they are untreated.

• Anxiety commonly occurs in combination with other mental or physical illnesses.


Sleep Disorders

• Between 50 and 70 million Americans have a sleep disorder.

• These disorders are many and may include the following problems:

– Narcolepsy—sudden irresistible sleep attacks of unknown origin lasting from seconds to minutes, two to six times a day

– Sleep apnea—a group of disorders characterized by cessation of breathing during sleep

– Sleepwalking—getting up and walking about while still asleep


Sleep Disorders (cont.)

• These disorders are many and may include the following problems (cont.):

– Night terrors—occur only in children, with periods of fright, crying, moaning, or screaming after a brief time asleep

– Excessive daytime sedation

– Insomnia


Selective Serotonin Reuptake Inhibitors

• Selective serotonin reuptake inhibitors (SSRIs) are a class of antidepressant drugs, some of which are now considered first-line therapy for anxiety disorders.

• Low serotonin levels are known to be present in severe stress and in many mood and anxiety-related disorders.

• SSRIs indirectly increase the amount of the neurotransmitter serotonin available in the synapses.

• SSRIs are generally well tolerated with few adverse effects.


Tricyclic Antidepressants

• The tricyclic antidepressants (TCAs) are another class of antidepressants.

• TCAs are as effective as the SSRIs in treating most anxiety disorders.

• TCAs work by affecting the regulation of serotonin or norepinephrine in the brain.

• TCAs have a higher adverse effect profile than SSRIs, which limits their use as antidepressants.


Monoamine Oxidase Inhibitors

• Monoamine oxidase inhibitors (MAOIs) are the oldest class of antidepressants.

• The MAOIs used to treat anxiety disorders are phenelzine (Nardil), tranylcypromine (Parnate), and isocarboxazid (Marplan).

• These drugs are occasionally prescribed for panic disorder and social phobia.


Monoamine Oxidase Inhibitors (cont.)

• Monoamine oxidase is the enzyme that degrades serotonin in the synapse.

• By inhibiting the enzyme, higher levels of serotonin can remain in the synapse and be active.

• The MAOIs are associated with a significant risk of a serious drug–food interaction.


Beta-Blockers

• Beta-blockers are adrenergic drugs most frequently used for a wide variety of cardiac conditions.

• Among other actions, they slow the heart rate.

• This helps the patient with some types of anxiety who may be uncomfortable and highly aware of the tachycardia and palpitations.


Benzodiazepines

• Benzodiazepines are used for a number of therapeutic effects.

• As a class, benzodiazepines appear to potentiate the effects of GABA.

• The result is more CNS depression than would normally be found.

• Benzodiazepines bind to specific receptor sites to produce their effects.

• As a drug class, benzodiazepines have a high margin of safety.


Question

• Benzodiazepines are used to treat which of the following condition(s)?

– A. Anxiety

– B. Seizures

– C. Alcohol withdrawal

– D. All of the above


Answer

• D. All of the above

• Rationale: Benzodiazepines are used for the following: anxiety relief, sleep promotion, anticonvulsant effects, muscle relaxation, treatment of acute alcohol withdrawal, induction of general anesthesia, preoperative sedation, and conscious sedation.


Lorazepam: Core Drug Knowledge

• Pharmacotherapeutics

– Used in treating anxiety disorders and insomnia

• Pharmacokinetics

– Administered: parenterally or orally. Distribution: body tissues. Metabolism: liver. Excreted: kidneys.

• Pharmacodynamics

– Increases the effects of GABA


Lorazepam: Core Drug Knowledge (cont.)

• Contraindications and precautions

– Hypersensitivity, psychoses, acute narrow-angle glaucoma, and use in children younger than 6 months

• Adverse effects

– Mild drowsiness, ataxia, confusion, respiratory disturbances, bradycardia, and hypotension

• Drug interactions

– Several drug interactions


Lorazepam: Core Patient Variables • Health status

– Asses for renal and hepatic impairment

• Life span and gender

– Pregnancy Category D

• Lifestyle, diet, and habits

– Assess the patient for the use of other CNS depressants.

• Environment

– Oral formulation can be given in any environment.

• Culture and inherited traits

– Longer T½ in Asians


Lorazepam: Nursing Diagnoses and Outcomes • Risk for Injury related to drowsiness and other adverse

effects

– Desired outcome: The patient will not sustain an injury while on lorazepam.

• Anxiety related to disease process

– Desired outcome: The patient will achieve symptom control.

• Deficient Knowledge related to newly prescribed drug therapy

– Desired outcome: The patient will learn the actions and adverse effects of lorazepam and how to safely self-administer the drug.


Lorazepam: Planning and Interventions

• Maximizing therapeutic effects

– Give at scheduled intervals throughout the day.

• Minimizing adverse effects

– If GI distress occurs, administer lorazepam with food.

– Monitor for paradoxical reactions and stop the drug if they occur.

– Dilute injectable lorazepam with an equal volume of compatible solution.


Lorazepam: Teaching, Assessment, and Evaluations

• Patient and family education

– Caution against use of alcohol with this drug.

– Discuss side effects of medication.

• Ongoing assessment and evaluation

– Lorazepam therapy is effective if the patient reports a reduction in feelings of anxiety.

– Throughout therapy, assess for therapeutic response and onset of adverse effects.


Question

• Lorazepam has a ________ duration of action?

– A. Short

– B. Intermediate

– C. Long

– D. Varies with route of administration


Answer

• A. Short

• Rationale: Lorazepam has a short duration of action; therefore, divide the daily dosage for treating anxiety into two or three doses and administer the drug throughout the day.


Buspirone

• Buspirone (BuSpar) is an azaspirodecanedione that is not chemically or pharmacologically related to the benzodiazepines.

• It is used to treat symptoms of anxiety, although exactly how it works is unknown.

• Optimum relief of anxiety usually occurs after 3 to 4 weeks of treatment.

• Buspirone is intended for short-term therapy; patients who have been treated with buspirone for up to 1 year have not required a dosage increase to maintain therapeutic effect.


Hydroxyzine

• Hydroxyzine (Vistaril) is a miscellaneous antianxiety drug.

• It exerts CNS depressant activity in subcortical areas.

• It rapidly produces a feeling of calm and relieves anxiety without impairing mental alertness.

• It may be coadministered with a narcotic to control pain while minimizing the nausea that may be an adverse effect from the narcotic.


Meprobamate

• Meprobamate (Equanil) is also used for short-term management of anxiety symptoms.

• Meprobamate has selective effects at multiple sites within the CNS, including the thalamus and the limbic system.

• It may also inhibit multineuronal spinal reflexes.

• It has mild tranquilizing properties and some anticonvulsant and muscle-relaxant properties.

• Meprobamate can produce several CNS adverse effects.

• Meprobamate is a Pregnancy Category D drug.


Eszopiclone

• Eszopiclone (Lunesta) is a nonbenzodiazepine hypnotic.

• The drug induces sleep quickly, prevents waking during the night.

• Eszopiclone is believed to achieve its therapeutic effect from interaction with GABA-receptor/benzodiazepine-receptor complexes.

• It is the only drug for insomnia that is approved for long-term use (up to 6 months of use).

• Eszopiclone has a rapid onset (within 1 hour) and is metabolized in the liver and excreted in the urine.

• The most common adverse effects of eszopiclone after 6 weeks of use were headache, prolonged drowsiness, and an unpleasant taste.


Zaleplon

• Zaleplon (Sonata) is a sedative for short-term use (up to 28 days).

• Although a nonbenzodiazepine and not chemically related to the benzodiazepines, it does interact with the GABA–benzodiazepine (BZ) complex.

• The most common adverse effects of zaleplon are drowsiness, dizziness, light-headedness, and difficulty with coordination. Zaleplon is a Pregnancy Category C drug.

• Zaleplon may lead to dependency, and rebound insomnia is possible.


Zolpidem

• Zolpidem (Ambien) is used for short-term treatment of insomnia—generally not for more than 7 to 10 days.

• It induces sleep rapidly and should be taken immediately before going to bed.

• Although zolpidem is not chemically related to the benzodiazepines, it does interact selectively with the GABA–BZ receptor complex and shares some pharmacologic properties with the benzodiazepines.

• Zolpidem generally preserves all of the sleep stages and has only minor effects on REM sleep.

• The most common adverse effects from zolpidem are headache, prolonged drowsiness, and dizziness.


Ramelteon

• Melatonin receptor agonists stimulate the same receptor sites as endogenous melatonin.

• Ramelteon (Rozerem) is used in the treatment of insomnia when the patient has difficulty falling asleep.

• Ramelteon has high affinity at two specific melatonin receptors.

• Common adverse effects of ramelteon include headache, daytime sleepiness, dizziness, tiredness, nausea, worsening insomnia, and colds.


Trazodone

• Trazodone (Desyrel) is an atypical antidepressant.

• This drug causes significant sedation as an adverse effect.

• Trazodone is most commonly used to promote sleep.


Chloral Hydrate

• Chloral hydrate is a nonbarbiturate hypnotic used to induce sleep and to cause preoperative sedation.

• It can be used as an adjunct to opiates and analgesics in pain control.

• In therapeutic doses, chloral hydrate has little effect on respirations, blood pressure, or reflexes.

• It does produce numerous adverse effects in the CNS.


Barbiturates

• Barbiturates such as phenobarbital (Bellatal), secobarbital (Seconal), and pentobarbital (Nembutal) were used to treat insomnia before the availability of the benzodiazepines.

• Although they are effective for short-term treatment of insomnia, they are also highly habit forming.

• Patients can develop tolerance and physical and psychological dependence on the drugs.

ppt chapter 15-1

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