Pharm - GAD, OCD, Insomnia Flashcards
What are the first line agents for the tx of GAD?
Antidepressants: SSRI and SNRI
Which psychic symptoms in patients with GAD that are best treated with SSRI and SNRI?
Apprehension and worry
Which antidepressants are preferred when a patient has GAD and depression?
- antidepressants are preferred over benzodiazepines
- antidepressants are effective treatments for both conditions (GAD and depression)
What is the time to onset of clinical effect when using antidepressants for GAD?
- for an SRI, it varies by patient but averages approximately 4 weeks.
- the initial therapeutic dose should be continued for 4-6 weeks.
What are the 2 meds used to augment the effects of antidepressants in the tx of GAD?
Anxiolytic: buspirone (Buspar®)
Anticonvulsant: pregabalin (Lyrica®, Schedule V) Not FDA approved for GAD
What is the time to onset of clinical effect when using buspirone or pregabalin in the treatment of GAD?
Buspirone should be given a trial of 4-6 weeks at the maximally tolerated dose before concluding it is ineffective.
Pregabalin minimum of 4-6 weeks at a maximally tolerated dose before concluding that it is not effective.
What is the drug of choice for rapid relief of acute anxiety sx?
Benzodiazepines are the drug of choice for rapid relief of ACUTE anxiety symptoms
What is the role of a benzodiazepine in the treatment of GAD when initiating an antidepressant?
- can be used as either monotherapy or, more commonly, as an adjunct to antidepressant treatment
- commonly used in GAD for acute management of anxiety and worry during the period before SSRIs or SNRIs take effect
- counteract the initial agitation often caused by the SSRI
- once the patient responds to the SSRI, the benzodiazepine can be tapered off gradually.
Which somatic symptoms in pts with GAD are best treated with benzodiazepines?
- restlessness
- increased fatiguability
- difficulty in concentrating
- irritability
- muscle tension
- sleep disturbance
Which autonomic symptoms in pts with GAD are best treated with benzodiazepines?
- shortness of breath
- palpitations,
- sweating
- dry mouth
- dizziness
- abdominal distress
- they generally lead to a reduction of emotional and somatic symptoms within minutes to hours, depending on the specific medication
Which patients are good candidates for long-term, low-dose benzodiazepines in the tx of GAD?
- patients with chronic GAD
- who have minimal current depressive symptoms
- who have no history of a substance use disorder
- do not develop tolerance to their anxiolytic effects, which would require dose increase
- experience only mild, tolerable withdrawal symptoms when the medication is tapered off
Which patients are poor candidates for long-term, low-dose benzodiazepines in the tx of GAD?
- h/o a substance abuse disorder
- patients who develop rapid tolerance
- increase their doses against medical advice
- exhibit withdrawal symptoms between doses
MOA of benzodiazepines (BZD)
Benzodiazepines exert their principal pharmacodynamic effect via central nervous system GABA receptors, potentiating the effects of endogenous GABA, the main inhibitory neurotransmitter.
**GABA receptors are membrane-bound proteins that primarily mediate neuronal excitability (seizures), rapid mood changes, clinical anxiety, sleep, memory, mood, and analgesia.
Which benzos are more likely to exert acute withdrawal symptoms?
Benzodiazepines with shorter elimination half-lives:
- alprazolam (Xanax)
- lorazepam (Ativan)
- etc.
Which benzos are less likely to exert acute withdrawal symptoms?
Benzodiazepines with longer elimination half-lives
- diazepam (Valium)
- clonazepam (Klonopin)
Describe the psychomotor retardation caused by benzodiazepines
- drowsiness, poor concentration, mental confusion
- ataxia, motor coordination, muscle weakness
- diplopia, vertigo
- slow reaction time and impaired driving skills increasing the risk of motor vehicle crashes
Describe memory impairment caused by BZD
Anterograde amnesia: impaired episodic memory – remembering recent events, circumstances under which they occurred and the time sequence
In patients who have used more than one year – specific deficits in visual-spatial ability and sustained attention.
Contraindications to BZD
Adverse effects in PREGNANCY:
- class D teratogen
- can cross the placenta and cause development of dependence and withdrawal in the fetus
- excreted in breast milk: contraindicated in breast-feeding mothers
Describe physiologic and psychologic dependence cause by BZD.
- develops sooner (1-2 months) in patients taking high dose of high-potency agents (example is alprazolam)
- withdrawal symptoms emerge with rapid dose reduction or abrupt discontinuation of the drug
- psychologic: overreliance on the need for the drug, loss of self-confidence and varying degrees of drug-seeking behavior
What is the primary cause of withdrawal symptoms in a patient taking a BZD?
any abrupt or overly rapid reduction in benzodiazepine (BZD)
Given a patient who abruptly stops a BZD, identify the withdrawal symptoms.
S/sx can include tremors, anxiety, perceptual disturbances, dysphoria, psychosis, and seizures.
What is the relationship between the half-life of BZD and withdrawal symptoms?
- the onset of withdrawal varies according to the half-life of the BZD involved
- sx may be delayed up to three weeks in BZDs with long half-lives, but may appear as early as 24 to 48 hours after cessation of BZDs with short half-lives.
Describe the the appropriate, safe withdrawal plan for benzodiazepine withdrawal from a patient.
- individualize the taper
- taper BZD slowly and gradually
One approach:
- 10-25% reduction of the initial dose every one to two weeks until the lowest dose is reached
- monitor the patient for symptoms of benzodiazepine withdrawal or relapse of GAD and slow the rate of dose reduction accordingly
- early signs of withdrawal include anxiety, dysphoria, and tremor; advanced manifestations include perceptual disturbances, psychosis, and seizures.
- if a patient has failed a previous tapering regimen, then try a slower taper over 6 months.
- augment taper with cognitive-behavioral therapy to improve the likelihood of success.
What is the place in therapy for mirtazapine?
Mirtazapine (Remeron) is a sedating antidepressant
-can be used as monotherapy or adjunctive treatment for GAD
