Psychopharmacology: Benzodiazepines, Lithium, Anticonvulsants, and Antidepressants

Benzodiazepines

Subclass for antianxiety medications including Restoril (temazepam), Librium (chlordiazepoxide), Valium (diazepam), Xanax (aprazolam), Klonopin (clonazepam), Ativan (lorazepam).

Action of GABA

Inhibitory neurotransmitter in the brain that reduces neuronal activity.

Indications for Benzodiazepines

Short term treatment of anxiety disorders and alcohol withdrawal.

Therapeutic Effects of Benzodiazepines

Sedation and skeletal muscle relaxation.

Side Effects of Benzodiazepines

Sedation (tolerance develops), dizziness, ataxia, and high addiction potential.

Benzodiazepine reversal for overdose

Flumazenil (romazicon).

Nursing considerations for Benzodiazepines

Do not take with alcohol, do not drive if sedated, eliminated in liver, may become toxic especially in the elderly.

Paradoxical effect of Benzodiazepines

Rare effects including excitement, anxiety, increased talkativeness, emotional release, excitement, and excessive movement.

Serotonergic subclass for antianxiety

Buspar (buspirone), which carries a risk of serotonin syndrome and is non-addicting.

Beta Blocker subclass for antianxiety

Inderal (propranolol), used for stage fright and is non-addicting.

Tricyclic TCA subclass for antianxiety

Approved for OCD: Anafranil (clomipramine).

SSRI subclass for antianxiety

Approved for OCD: Luvox (fluvoxamine), Zoloft (sertraline), Paxil (paroxetine), Prozac (fluoxetine).

Mood Stabilizers/Antimanic

Eskolith, Lithobid (lithium carbonate).

Action of Lithium

Exact mechanism unknown; stabilizes reuptake mechanisms at the synapse, reduces excitatory neurotransmitters (dopamine & glutamate) and increases inhibitory GABA receptors.

Indications for Lithium

Bipolar Mania.

Therapeutic Effects of Lithium

Calms mania.

Side Effects of Lithium

Slight tremor, dull headache, metallic taste, polydipsia, polyuria.

Narrow therapeutic window for Lithium

0.5-1.2 mEq/L.

Toxicity level for Lithium

Blood level >1.5 mEq/L.

Symptoms of Lithium toxicity

Disrupts muscle conduction: coarse tremor, GI upset, confusion, ataxia, dysarthria, seizure, coma, death.

Mood Stabilizer/Anticonvulsants

Includes Depakote (divalproex sodium), Tegretol (carbamazepine), Trileptal (oxcarbazepine), Lamictal (lamotrigine), Topamax (topiramate).

Action of Anticonvulsants

Affects sodium & calcium channels, increases GABA, decreases glutamate.

Indications for Anticonvulsants

Bipolar Mania; Lamictal also works for Bipolar depression and controls agitation/aggressive behavior.

Therapeutic range for Depakote

50-100.

Therapeutic range for Tegretol

8-12.

Side Effects of Lamictal

Can cause severe, life-threatening rash (Stevens-Johnson Syndrome).

Side Effects of Depakote

Hepatotoxicity, pancreatitis, and leukopenia.

Side Effects of Tegretol

Bone marrow suppression and agranulocytosis.

Nursing considerations for Anticonvulsants

Monitor liver function, pancreatic function, platelet count, and white blood cell count.

Monitoring for Anticonvulsants

Watch for fever, chills, muscle aches, and sore throat (indicators of agranulocytosis).

Agranulocytosis

Monitor for fever, chills, muscle aches & sore throat.

Tegretol

Avoid grapefruit because it increases medication level.

Hematological manifestations

Teach patient about fever, sore throat, pallor, weakness, infection, easy bruising.

MAOI's (Monoamine Oxidase Inhibitors)

Subclass of antidepressants used to treat atypical depression and depression resistant to other medications.

Nardil, Parnate, Marplan, Selegeline Patch

Examples of MAOIs used to treat Parkinson's.

Action of MAOIs

Prevent breakdown of norepinephrine, tyramine, serotonin & dopamine.

Therapeutic Effects of MAOIs

Energy, other symptoms of depression lift, THEN depressed mood lifts.

Side effects of MAOIs

Hypotension (postural), insomnia, sexual dysfunction, weight gain.

Low tyramine diet

Teaching for MAOIs includes avoiding aged/smoked/fermented foods.

Hypertensive crisis

Symptoms of hypertension should be treated immediately by a doctor.

TCA (Tricyclic Antidepressants)

Subclass of antidepressants known for potential deadly overdose.

Elavil, Tofranil, Anafranil, Pamelor, Norpramin & Sinequan

Examples of TCAs.

Action of TCAs

Prevent reuptake of norepinephrine & serotonin.

Indications for TCAs

Used for depression, enuresis, OCD, & other anxiety disorders.

Side effects of TCAs

Primarily sedation & anticholinergic effects, weight gain, cardio-toxicity.

Suicide assessment for TCAs

Toxic in doses equivalent to 3 weeks supply.

SSRIs (Selective Serotonin Reuptake Inhibitors)

Subclass of antidepressants that includes Prozac, Paxil, Celexa, Luvox, Zoloft, Lexapro.

Action of SSRIs

Prevent reuptake of serotonin.

Indications for SSRIs

Used for depression, anxiety, & eating disorders.

Therapeutic Effects of SSRIs

Energy, other symptoms of depression lift, THEN depressed mood lifts; takes 4-6 weeks for full effect.

Side effects of SSRIs

GI symptoms, hyponatremia, insomnia, headache, sweating, drowsiness, sexual dysfunction, increased bleeding risk.

Adverse effects of SSRIs

Serotonin Syndrome: excess CNS activity with symptoms like agitation, confusion, dilated pupils, increased BP/Pulse.

Black Box Warning for SSRIs

Agitation & suicidal/homicidal ideation.

SNRI (Serotonin Norepinephrine Reuptake Inhibitors)

Includes Effexor (Venlafaxine), Pristiq (Desvenlafaxine), Cymbalta (Duloxetine).

Tetracyclic

Example is Remeron (Mirtazapine).

NDRI (Norepinephrine, Serotonin & Dopamine Reuptake Inhibitor)

Example is Wellbutrin (Bupropion), major action on dopamine.

Increased risk with NDRI

Increased risk for agitation/aggression & suicidal thoughts.

Seizure precautions

Measures taken to prevent seizures.

Cardiac arrhythmia

An irregular heartbeat.

Activation of mania

A state of heightened mood and energy.

Typical Antipsychotics

A category of antipsychotic medications that include Thorazine and Haldol.

Atypical Antipsychotics

A category of antipsychotic medications that include Clozaril, Zyprexa, and Abilify.

Dopamine action

The mechanism by which typical antipsychotics block dopamine receptors.

Positive symptoms of psychosis

Symptoms such as hallucinations that are treated with antipsychotics.

Therapeutic Effects of Typical Antipsychotics

Rapid sedation of agitation/aggression and reduction of psychotic symptoms.

Extrapyramidal side effects (EPS)

Movement disorders caused by antipsychotic medications.

Tardive Dyskinesia (TD)

A late-onset side effect characterized by abnormal, uncontrollable movements.

High Potency Antipsychotics

Antipsychotics like Haldol that have a higher risk of EPS and TD.

Low Potency Antipsychotics

Antipsychotics like Thorazine that have a lower risk of TD.

Anticholinergic side effects

Side effects resulting from anticholinergic medications, including dry mouth and constipation.

Postural hypotension

A drop in blood pressure upon standing.

Fall safety

Precautions taken to prevent falls in patients.

AIMS test

A standardized test used to assess EPS and TD.

Clozaril

An atypical antipsychotic known for the risk of agranulocytosis.

Selective blocking of dopamine

The mechanism of action for atypical antipsychotics.

Positive & Negative symptoms of psychosis

Symptoms treated by atypical antipsychotics.

Black Box Warning

A warning indicating increased mortality in elderly patients with dementia-related psychosis.

Neuroleptic Malignant Syndrome

A life-threatening condition characterized by severe muscle stiffness and autonomic instability.

Metabolic Syndrome

A cluster of conditions including increased lipids and blood glucose.

Treatment of EPS

Reducing the dosage of antipsychotic medication or adding anticholinergic medication.