CHAPTER 19 Psychiatric Disorders
I. Introduction
II. Anxiety disorders
A. Types
1. Generalized anxiety disorder (GAD): 6 months or more of excessive worry or anxiety generally with an unidentified cause
2. Panic disorder: discrete periods of sudden intense fear or terror and feelings of impending doom. Usually the precipitating cause is not known; the patient can become conditioned to believe it is caused by some environmental cause. Disorder can lead to agoraphobia: fear or avoidance of certain situations (e.g., going to the store) because they think they will have an attack.
3. Obsessive-compulsive disorder (OCD): characterized by obsessive or intrusive thoughts that one cannot control and that are repetitive in nature: ritualistic behaviors (e.g., repetitive hand washing, combing the hair, cleaning the house)
B. Treatments
1. Benzodiazepines (Table 19-1)
III. Schizophrenia
| Agent | Half-life (hours) | Equivalent Dose (mg, approximate only) |
|---|---|---|
| Alprazolam (Xanax) | 6–12 | 1 |
| Chlordiazepoxide (Librium) | 5–30 | 25 |
| Diazepam (Valium) | 20–100 | 10 |
| Lorazepam (Ativan) | 10–18 | 1 |
| Oxazepam (Serax) | 4–15 | 10 |
A. Signs and symptoms
1. Positive
B. Four phases
1. Prodromal
IV. Mood disorders
A. Depression
1. Major depressive disorder
4. Tricyclic antidepressants (TCA)
5. Serotonin reuptake inhibitors (SSRI)
e. Examples
(3) Sertraline (Zoloft)
6. Monoamine oxidase inhibitors (MAOI)
a. Monoamine oxidase breaks down norepinephrine, epinephrine, dopamine, and serotonin; interference causes neurotransmitters to accumulate in the synapse
b. May increase tyramine and cause hypertensive crisis (headache, stiff neck, palpitations, chest pain, increased or decreased heart rate, nausea/vomiting, pyrexia, chills, flushing), cerebrovascular accident, death
c. Tyramine is broken down by MAO-A, and inhibiting its action may result in excessive build-up of tyramine. Patients taking MAOI should limit intake of foods that contain tyramine, including aged cheese, wines like Chianti, broad bean (fava bean) pods, chocolate, soy sauce, and others.
7. Atypical antidepressants
d. Venlafaxine (Effexor)
B. Bipolar disorder
5. Treatment
b. Lithium
(4) Target blood level for acute phase management: between 0.8 and 1.2 meq/L; maintenance levels: 0.6–1.2 meq/L
c. Valproate (Depakote)
(1) Mechanism of action: causes increased availability of the inhibitory neurotransmitter, gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, to brain neurons or may enhance the action of GABA
d. Carbamazepine (Tegretol)
(1) Usual adult dose
Table 19-2 Atypical Antipsychotics Comparison Table
| Generic/Brand Name | Typical Adult Oral Dose | Comments |
|---|---|---|
| Risperidone (Risperdal) | Initial 1–2 mg dailyMaintenance 2–6 mg daily (average dose 4 mg daily) | |
| Olanzapine (Zyprexa) | Initial 5–10 mg daily Maintenance 30 mg daily | |
| Quetiapine (Seroquel) | ||
| Ziprasidone (Geodon) | ||
| Paliperidone (Invega) | 3–12 mg at bedtime | |
| Aripiprazole (Abilify) | 10–30 mg at bedtime | |
| Clozapine (Clozaril) | 400 mg at bedtime | First atypical antipsychotic agent, with low risk of EPS but high risk of agranulocytosis; frequent WBC monitoring is required |
PATIENT PROFILE
Current Medical Problem: AC is a married female with one child (6 years old) who lost her mother to cancer about 7 months ago. She reports that she just “has not been the same” since that time, and has continual difficulty coping with the loss of her “best friend”. She is tearful when talking about her family. She feels overwhelmed by her daily tasks as a mom, has a hard time getting motivated to do daily activities, and has recently even stopped her running program. It is difficult to concentrate on needed work, and she “feels like sleeping all the time”. She does not interact with friends the way she used too. She states she has a supportive husband and loves her family, but it is just hard to get through the day and “feel worthwhile”.
Diagnosis: AC finally went to her family practitioner, who recommended she begin meeting with a family therapist and psychologist, and has prescribed a new prescription for Paxil.
PATIENT PROFILE QUESTIONS
1. The patient’s current diagnosis is most likely:
Answer: II. AC’s symptoms are most consistent with a major depression episode. Her symptoms do not appear to coincide with a particular season (e.g., winter), and she does not describe the typical “ups and downs” in mood (mood swings) seen in patients with bipolar disorder.
2. What should be the usual initial starting and maximum dose of Paxil (immediate release) for depression in a younger healthy adult?
Answer: II. Paxil has many dosing regimens, depending on the condition to be treated. Answer II gives the usual dosage range for a healthy young adult for depression. If the patient had hepatic disease, then the initial dose would be 10 mg/day. The dosage for Paxil CR would be 25 mg/day initially, up to 62.5 mg/day PO.
3. After 8 weeks, AC is beginning to feel like herself again. How long should her Paxil prescription be continued?
III. There is not an exact answer; stopping medication too soon may cause depression to return. Usually patients are evaluated every 6 months after becoming euthymic.
Answer: III. It takes several weeks to see the full effect of antidepressant treatment; AC is just beginning to respond fully to the medication, so answer II is not correct. Many patients do not understand depression treatment and stop their medication too soon in the process, risking relapse. Answer I is a wrong answer, because it does not state that the patient’s symptoms have responded and resolved in the 1-year period; the 1-year period would be an arbitrary endpoint. Answer III is the best answer since there is no exact length of time and therapy is individualized to patient response. In patients with recurrent episodes, treatment may be indefinite. In patients who have had only one episode, most experts continue antidepressants for several months after all symptoms have resolved.
Answer: d. Patients taking a “triptan” containing medication like Treximet need to be informed about the possibility of serotonin syndrome, and the signs and symptoms of serotonin syndrome. The risk of serotonin syndrome seems to be highest from the serotonergic medications when Paxil is started or a Paxil dose is increased. Alcohol can worsen depression, and alcohol is generally best avoided in any patient taking antidepressant medications. Because patients with depression taking antidepressants are at increased risk of suicide, any worsening of symptoms should be promptly reported. Paxil and other selective serotonergic reuptake inhibitors (SSRIs) have been associated with adverse fetal effects, and AC should inform her doctor of any wish to become pregnant while on Paxil so treatment may be re-evaluated prior to pregnancy. SSRIs have been associated with a discontinuation syndrome when suddenly halted. A patient should not halt treatment suddenly, and, even when the doctor decides discontinuation is advisable, the dose should be gradually tapered down before completely ending therapy. A MedGuide is available that helps explain some of these important counseling points to patients and should be dispensed with each new prescription and refill for Paxil.
REVIEW QUESTIONS
(Answers and Rationales on page 371.)
4. The majority of antipsychotic medications work by reducing the levels or activity of which substance?
7. A patient presents to a clinic with complaints of right face and neck stiffness. The patient is taking fluphenazine. What reaction is this patient having, and what is the treatment?
8. A 25-year-old man was diagnosed with bipolar disorder several months ago but has experienced no improvement in symptoms with lithium therapy. What is an appropriate alternative?
9. Which of the following therapeutic interventions is recommended for the treatment of schizophrenia in addition to antipsychotic medication?
14. Which of the following foods and/or beverages should not be ingested by patients taking isocarboxazid?
16. An otherwise healthy 28-year-old man is diagnosed with major depressive disorder. Which of the following is the most appropriate initial therapy?
17. A 20-year-old woman is taken to the emergency department by her family for “psychotic behavior.” She is admitted and later diagnosed with schizophrenia. Which of the following is the most appropriate therapy at this time?
18. Which of the following serotonin reuptake inhibitors may cause memory impairment, menstrual irregularities, and akathisia?
28. Patients with a history of hypersensitivity to tricyclic antidepressants should not be given which of the following?
32. A patient with a medical history significant for major depressive disorder (MDD) is diagnosed with new-onset hypertension. Based on her history of MDD, what medication should be avoided in this patient?
34. Which of the following lithium levels is within the therapeutic range during initiation of therapy?
35. A patient is referred to a psychiatric clinic for a major affective disorder. Which of the following medications will provide immediate onset of action?
47. Which of the following medications may provoke serotonin syndrome in a person who recently received a selective serotonin reuptake inhibitor?
56. A patient is taken to the hospital after taking an overdose of chlorpromazine. He is hypotensive and is given IV epinephrine. Immediately following the injection, blood pressure becomes undetectable. What is the likely cause?
58. Which antidepressant would you choose for a patient with sleep disturbances and is least likely to cause anticholinergic effects?
63. A patient on several medications eats a meal of wine and cheese and develops hypertension. What is the most likely cause?
68. A 35-year-old woman is diagnosed with neurotic depression. During the course of her treatment a clinician prescribes amitriptyline. She calls 5 days later and says she has not received any relief of her depressive symptoms. What is the most appropriate next step?
72. Antipsychotic drugs block what receptors to produce constipation, dry mouth, and urinary retention adverse effects?
