Transcript Chapter 16 Cholinesterase Inhibitors

Drugs for Bipolar Disorder
Bipolar Disorder
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Formerly known as manic-depressive illness
Afflicts an estimated 3.7% of the adult
population
Mainstays of therapy
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Lithium, valproic acid
Many also receive an antipsychotic
Chronic condition that requires lifelong
treatment
Bipolar Disorder
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Definition of bipolar disorder (BPD)
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Cyclic disorder
Recurrent fluctuations in mood
Episodes of mania and depression persist for
months without treatment
Treatment
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Drugs
Psychotherapy
Characteristics of Bipolar Disorder
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Types of mood episodes seen in bipolar
disorder (BPD)
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Pure manic episode (euphoric mania)
Hypomanic episode (hypomania)
Major depressive episode (depression)
Mixed episode
Patterns of Mood Episodes
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Subdivided into two major categories
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Bipolar I disorder
• Manic or mixed episodes
• Usually depressive episodes
Bipolar II disorder
• Hypomanic or depressive episodes
• Not manic or mixed episodes
Treatment of Bipolar Disorder
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Drug therapy
Nondrug therapy
Drug Therapy
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Types of drugs employed
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Mood stabilizers (Lithium)
• Relieve symptoms during manic and depressive
episodes
• Prevent recurrence of manic and depressive episodes
• Do not worsen symptoms of mania or depression; do not
accelerate the rate of cycling
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Antipsychotics
• Given during severe manic episodes
Antidepressants
• Given during depressive episodes
Drug Therapy
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Drug selection
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Short-term therapy: manic episodes
Short-term therapy: depressive episodes
Long-term preventive treatment
Promoting compliance
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Short-term hospitalization
Long-term prophylactic therapy
Education for both patient and family
Nondrug Therapy
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Education
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Psychotherapy
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Patient and family
Individual, group, family
Electroconvulsive therapy
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Last resort
Mood-Stabilizing Drugs
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Lithium
Antiepileptic drugs
Lithium (Lithonate, Lithotabs)
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Chemistry
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Simple inorganic ion
Found naturally in animal tissues
Therapeutic uses
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Bipolar disorder
Other uses
• Alcoholism
• Bulimia
• Schizophrenia
• Glucocorticoid-induced psychosis
Lithium (Lithonate, Lithotabs)
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Mechanism of action
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Altered distribution of certain ions
Altered synthesis and release of norepinephrine,
serotonin, and dopamine
Mediates intracellular responses to
neurotransmitters
Shown to facilitate regeneration of damaged optic
nerves
Can increase total gray matter in regions known to
atrophy in BPD
Lithium (Lithonate, Lithotabs)
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Pharmacokinetics
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Absorption and distribution
Excretion
• Short half-life
• Excreted by the kidneys
• Sodium levels: lithium excretion reduced when sodium
level low
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Plasma levels
• 0.8–1.4 mEq/L
Lithium (Lithonate, Lithotabs)
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Adverse effects
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Excessive lithium levels
• Greater than 1.5 mEq/L
• Monitor levels q 2–3 days at initiation of therapy and then
q 3–6 months
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Therapeutic lithium levels
• Gastrointestinal
• Tremors
• Polyuria
• Renal toxicity
• Goiter and hypothyroidism
• Teratogenesis
Lithium (Lithonate, Lithotabs)
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Drug interactions
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Diuretics
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Anticholinergic drugs
Preparations, dosage, and administration
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Lithium carbonate
Lithium citrate
Dosage is highly individualized
Antiepileptic Drugs
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Divalproex sodium (Valproate)
Carbamazepine
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Reduces symptoms
Protects against recurrence of mania and
depression
Target trough plasma level: 4–12 mcg/mL
Lamotrigine
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Indicated for long-term maintenance
Can be used alone or in combination
Antipsychotic Drugs in BPD
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Used to acutely control symptoms during
manic episodes
Used long term to help stabilize mood
Benefit patients with or without psychotic
symptoms
Can be combined with mood stabilizer
Five antipsychotics approved for use
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Olanzapine (Zyprexa), quetiapine (Seroquel),
risperidone (Risperdal), aripiprazole (Abilify), and
ziprasidone (Geodon)