Pharmacology: Anxiety, Insomnia, Sedation, and Smoking Cessation
Central Nervous System Depressants Classification
Antianxiety Agents: Also known as anxiolytics, these medications are designed to manage states of nervousness and tension.
Sedative-Hypnotics: These agents are primarily used to induce sleep and treat insomnia.
Understanding Anxiety
Definition: Anxiety is characterized by feelings of nervousness, tension, and worry. It is considered an unpleasant feeling arising as a response to various threatening situations including physical, emotional, economic, social, or educational growth (e.g., test-taking).
Continuum of Anxiety: Anxiety exists on a spectrum, ranging from normal, situational stress to a full psychiatric classification as a disorder.
Neuroendocrine Factors:
Primarily involves the noradrenergic system.
May be caused by an excess of norepinephrine.
Likely associated with a depletion of gamma-aminobutyric acid (GABA).
Physical Symptoms of Hyperarousal:
Panic.
Restlessness.
Tremors.
Palpitations.
Hyperventilation.
Major Anxiety Disorders:
GAD: Generalized Anxiety Disorder.
OCD: Obsessive-Compulsive Disorder.
Panic Disorder.
PTSD: Post-Traumatic Stress Disorder.
SAD: Social Anxiety Disorder.
SAD: Seasonal Affective Disorder.
Non-Pharmacologic Management of Anxiety and Sleep
Therapeutic Interventions:
Psychotherapy.
Behavioral Modification Therapy.
Exercise.
Creating a calm environment.
Aromatherapy.
Laughter.
Complementary and Alternative Medicine (CAM).
Yoga.
Sleep Hygiene Protocols:
Follow a consistent routine.
Avoid doing other activities in bed (the bed is only for sleep).
Do not exercise immediately before bedtime.
Avoid stimulants or ethanol (ETOH) at night.
Avoid agitation or stressful activities before sleep.
Warm Milk: Often considered an urban legend, though it contains tryptophan.
Overview of Sleep and Insomnia
The Sleep Cycle:
Stage 1: Drowsiness with slow eye movement.
Stage 2: Eye movement ceases.
Stage 3: Deep sleep (non-REM).
Stage 4: Deep sleep (REM).
Psychological Complications of Insomnia:
Lower performance levels.
Slowed reaction times.
Increased risk of depression.
Increased risk of anxiety disorders.
Physiological Complications of Insomnia:
Overweight or obesity.
High blood pressure (hypertension).
Poor immune system function.
Risk of heart disease.
Risk of diabetes.
Benzodiazepines: Pharmacology and Use
Mechanism of Action: Benzodiazepines cause Central Nervous System (CNS) depression by binding with benzodiazepine receptors in the brain, which are involved in GABA binding sites.
Controlled Substance Status: Classified as Class IV substances.
Therapeutic Properties: Wide therapeutic range, but can lead to physical dependence.
Duration of Treatment Guidelines:
Benzos should be used for the shortest period possible.
For Anxiety: Managed for less than 4 months ($< 4\text{ months}$).
For Insomnia: Managed for less than 3 weeks ($< 3\text{ weeks}$).
Pharmacokinetics:
Routes: Oral and IV are preferred. IM can be used in emergency situations. Other routes include rectal and insufflation.
Distribution: Lipid-soluble agents that cross the blood-brain barrier.
Metabolism: Metabolized by the liver; half-lives vary between specific drugs.
Therapeutic Uses:
Relief of anxiety and sleep disorders.
Anticonvulsant properties.
Conscious sedation (provides short-term amnesia).
Preoperative sedation.
Prevention of agitation, seizures, and delirium tremens (DTs) during ethanol (ETOH) withdrawal.
Treatment of muscle spasms and status epilepticus.
Often used concurrently with SSRIs, antipsychotics, and mood stabilizers.
Contraindications and Cautions:
Contraindicated in individuals with sleep apnea.
Contraindicated in cases of severe respiratory depression.
Contraindicated in severe liver or kidney disease.
Use with caution in individuals with a history of drug abuse or ETOH use.
Benzodiazepine Withdrawal: Abrupt cessation after physical dependence has developed can cause withdrawal symptoms. Medications must be tapered and gradually discontinued.
Interactions:
Mixing with alcohol or other CNS depressants (like opioids) increases the risk of CNS depression.
Herbals such as kava-kava, valerian, or chamomile can increase sedative effects.
Specific Benzodiazepine Drugs:
Diazepam (Valium).
Alprazolam (Xanax).
Lorazepam (Ativan).
Chlordiazepoxide (Librium).
Clonazepam (Klonopin).
Midazolam (Versed).
Toxicity and Antidote:
Primary symptom of toxicity: Respiratory depression.
Antidote: Flumazenil (Romazicon).
Non-Benzodiazepine Antianxiety Agents
Buspirone (Buspar):
Profile: Usually non-sedating with no potential for abuse.
Action: Increases norepinephrine.
Therapeutic Use: Relief of anxiety.
Adverse Effects:
Cardiovascular: Chest pain, palpitations, tachycardia, hypertension, hypotension, syncope.
Vision: Blurred vision.
GI: Nausea, constipation, dry mouth.
CNS: Dizziness, drowsiness, incoordination.
Interactions: Grapefruit increases the risk of toxicity.
Nursing Interventions for Buspirone:
Assess chest pain, heart rate/rhythm, and BP.
Implement fall precautions (nonskid slippers).
Small frequent meals and frequent oral hygiene (non-alcohol based products) for dry mouth.
Increase fiber and fluids for constipation.
Other Pharmacologic Agents for Anxiety and Sleep
Other Anxiety Classifications:
SSRIs.
MAOIs.
Antihistamines.
Antipsychotics.
Beta Blockers.
Specific Sleep Aids:
Chloral hydrate (Noctec): Now off the market in the U.S.
Eszopiclone (Lunesta).
Ramelteon (Rozerem).
Zaleplon (Sonata).
Zolpidem (Ambien).
Hydroxyzine (Vistaril).
Melatonin.
Suvorexant (Belsomra): A newer drug classified as an orexin receptor antagonist.
Barbiturates:
Used for sedation, hypnosis, anesthesia, and inducing coma.
Example: Phenobarbital (Luminal).
Smoking Cessation Medications
Bupropion (Wellbutrin/Zyban): An antidepressant used to aid smoking cessation.
Varenicline (Chantix):
Solely a smoking deterrent.
Not a benzodiazepine or anxiolytic.
Mechanism: Nicotine receptor partial agonist.
Risk: Severe psychotic side effects.
Nicotine Substitutes: Replacing nicotine with specific nicotine delivery systems.
Nursing Functions and Education
Patient Education: Essential for all CNS depressants.
Paradoxical Response: Monitor for responses opposite to what is expected.
Pregnancy: Advise patients to avoid pregnancy while on these medications.
Dosing Philosophy: Start with the lowest possible dose for the shortest possible time.
Safety: Provide a safe environment with fall precautions, call bells within reach, and nonskid slippers. Advise patients not to drive or operate heavy machinery.
Case Studies and Clinical Questions
Case Study 1 (Thomas Downey):
Patient: 42-year-old male hospitalized for severe depression and insomnia.
History: Allergic to benzodiazepines. Vital Signs: HR , Resp , BP , Pulse Ox . History of ankle fracture.
Clinical Consideration: Because he is allergic to benzos, alternative sleep aids must be chosen.
Medication Calculation (Clarissa Brown):
Order: Nafcillin (Nallpen) IVPB every 6 hours.
Reconstitution: Add to vial. Add to of .
Administration: Over 15 minutes.
Calculation for IV Pump Flow Rate:
NCLEX Question: For a client with severe GAD requiring immediate stabilization, Alprazolam (Xanax) is the most effective agent among the choices (Venlafaxine, Buspirone, Paroxetine) due to its rapid onset compared to antidepressants or buspirone.