Anxiety Drugs Flashcards
(29 cards)
Drug classes to treat anxiety?
Benzodiazepines Azapirones Serotonin Specific Reuptake Inhibitors (SSRI) Serotonin & NE Reuptake Inhibitors Antihistamines
MOA of BDZs?
BDZ’s bind to specific sites which are separate from but adjacent to the receptor for GABA. BDZ receptors are found in CNS & location parallels GABA neurons. Binding of BDZs enhances the affinity of GABA receptors, resulting in more frequent opening of adjacent Cl- channels resulting in hyper polarization and inhibition of neuronal firing
What are the 2 BDZ receptors?
BZ1- assoc w/ sleep
BZ2- assoc w/ memory, motor, sensory & cognitive function (muscle relaxation, ataxia, emotional behavior, anxiolytic effects
BDZ Pharmacokinetics
BDZ are lipid soluble and taken up rapidly in the brain and other perfused organs. They then get redistributed to tissue less well perfused. They do cross the placenta & get secreted into breast milk
BDZ Metabolism
undergo hepatic metabolism to water soluble compounds for elimination
Short Acting BDZ
Lasts 3-8 hours
Oxazepam- good for elderly & those w/ hepatic disease. Has no active metabolites
Intermediate BDZ
Lasts 3-8 hours
Lorazepam- good for elderly & those with hepatic disease
Alprazolam
Long Acting BDZ
Lasts 1-3 days
Chlordiazepoxide
Diazepam
Clorazepate- prodrug, must be converted to active metabolite
Adverse effects of BDZ
Drowsiness & confusion Ataxia Cognitive Impairment Potentiate alcohol & other CNS depressants Tolerance is common w/ BDZ
What is a BZD Antagonist?
FLUMAZENIL- binds to specific sites, where it competitively antagonizes the binding and allosteric effects of BDZ’s
Indications: suspected BDZ overdose, reverse sedative effects administered during anesthesia
Buspirone
Actions are mediated by serotonin receptors (5HT1a). 5HT1a are mostly somatodendritic auto receptor that are coupled to G proteins regulating k+ membrane channel. Increase opening- hyperpolarizes the neuron and decreases firing
Buspirone is a partial agonist
Has a slow onset (2 weeks)
No physical dependence/ withdrawal syndrome
SSRI MOA?
Selectively inhibit the reuptake of serotonin at the transporter. By blocking neurotransmitter removal serotonin concentration increases in the synaptic cleft
SSRI Drugs
Paroxetine- social anxiety disorder Sertaline- used in PTSD Escitalopra SSRI's don't have physical dependence and do not potentiate CNS depression of alcohol. SSRI's have a delayed onset
SSRI Adverse Reactions
CNS- insomnia, tremor
CV- palpitations, hypotension, vasodilation
GI- anorexia
GU- loss of libido, sexual dysfunction
SSRI Drug Interactions
MAOI’s can cause fatal reactions. If pt taking MAOI’s and switch to SSRI’s wait 14 days before starting. Get “serotonin syndrome”- hyperthermia, muscle rigidity, myoclonus, rapid changes in mental status
SNRI MOA
blocks serotonin & NE reuptake transporters
What is Venlafaxine?
SNRI
Used to general anxiety disorder
Adverse: Similar to SSRI; can also cause hypertension
DO NOT abruptly discontinue- slowly titrate the pt off the drug
Antihistamines MOA
Antagonist at H1 receptors located in hippocampus and cortex
Antihistamine Agents
Piperazine derivative Hydroxyzine HCL Hydroxyzine Pamoate Used to General Anxiety Disorder Adverse: Sedation. Do not combine w/ alcohol
Drugs to treat Insomnia
Benzodiazepines
Miscellaneous
Short Acting Hypnotic BDZs
last 3-8 hours
Midazolam- used as preanesthetic and intraoperative medication. Given as an oral syrup
Triazolam-Used to induce sleep in patients w/ recurring insomnia
tolerance develops in a few days
withdrawal results in rebound insomnia
Intermediate BDZ’s
Lasts 10-20 hours
Temazepam
Estazolam- useful in pt who experience frequent wakening, peak sedative effect occurs 2-3 hours after oral dose
Long Acting BDZ’s
Lasts 1-3 days
Quazepam
Flurazepam- significantly reduces sleep-induction time, decreases number of wakening, increase duration of sleep
Contraindication of BDZ
Patient’s with obstructive sleep apnea b/c they decrease muscular tone in upper airway and exaggerate the impact of the episodes of apnea
Do not combine w/ alcohol