CNS Agents Flashcards
__etine, __opram
SSRI Antidepressant
Prevent reuptake of Serotonin, potentiating its effects. Most common antidepressant type. Rx for depression, anxiety disorders, OCD, PDD, eating disorders. SE: sexual dysfunction, GI upset, loss of appetite, tremors.
DO NOT give SSRIs with MAOIs. Serotonin syndrome: mental status changes, muscle stiffness, hyperthermia.
Ex: Paroxetine, Fluoxetine (inhibit P-450), Dapoxetine, Escitalopram, Citalopram, Fluoxamine, Sertraline, Zimelidine.
__triptyline, __ipramine
Tricyclic Antidepressants
Serotonin/NE reuptake inhibitors. Less common use than SSRIs b/c also inhibit M, H, a-adrenergic receptors, leading to side effects.
Rx for major depression, panic disorders, enuresis, chronic pain. SE: sedation (H block), postural hypotension and arrhythmia (a block), cant see/pee/shit/spit (antiACh at M).
DO NOT give TCAs with MAOIs, seizures result. Overdose: EKG changes (widened QRS), arrhythmias, mental status changes, seizures.
Ex: Amitriptyline, Nortriptyline, Doxepin, Imipramine, Desipramine. Second generation: Amoxapine, Trazodone (Rx insomnia, cause priaprism), Buproprion (smoking cessation).
Nefazodone, Mirtazapine, Venlafaxine, Maprotiline
Heterocyclic Antidepressants
Block reuptake of NE/Serotonin. M: inhibits activation of a2-adrenergic and 5HT2 receptors, increasing release of NE/Serotonin
Rx of depressive disorders and GAD. SE: sedation, increased appetite and weight gain, HTN and increased HR.
Ex: Nefazodone, Mirtazapine, Venlafaxine, Maprotiline.
Tranylcypromine, Phenelzine, Isocarboxazid
MAOIs, Monoamine Oxidase Inhibitors.
Levels of NE, Serotonin, and DA increase because it wipes out Monoamine oxidase, which metabolizes them. Leak out into the synape and activate Serotonin and NE receptors.
Rx of atypical depression, phobias, panic disorder. SE: sedation, hypotension, blurred vision, weight gain. Can’t degrade tyramine in wine, cheese, and smoked meats. Leads to a hypertensive crisis (HA, arrhythmia, HTN) when builds up and stimulates release of EPI/NE.
Ex: Tranylcypromine, Phenelzine, Isocarboxazid.
Lithium
Antipsychotic
MOA not understood. May inhibit the phosphoinositol second messenger cascade and interfere with synthesis, storage, release, and reuptake of Serotonin/DA/NE.
Rx as a mood stabilizer for bipolar disorder. Combine with other Rx for schizoaffective disorder, schizophrenia, psychotic feature mood disorders. SE: fine hand tremor, hypothyroidism, ECG changes, nephrogenic diabetes insipidus (ADH antagonism - hypernatremia, polyuria, polydipsia). Risk of intoxication, monitor.
Dantrolene
Muscle relaxer. Rx of Neuroleptic Malignant Syndrome from antipsychotic drugs: muscle rigidity, altered mental status, hypothermia, autonomic instability. Or use DA agonist (Levodopa, Bromocriptine, Amantadine).
__operidol, Fluphenazine
Typical Antipsychotic Agents. High potency.
Blocks postsynaptic D2 receptors in limbic system, decreasing response to DA excitation. Some inhibition at H1, cholinergic, and a-adrenergic receptors, leads to side effects.
Rx positive symptoms of schizophrenia (delusions, hallucinations), Tourettes, delirium, agitation. SE: sedation (H), anticholinergic effects, orthostatic hypotension (a), extrapyramidal signs (dystonia, akinesia, akathisia, tardative dyskinesia) from DA blockade, increased prolactin (galactorrhea, amenorrhea) from lack of DA inhibition of pituitary.
Neuroleptic malignant syndrome: muscle rigidity, altered mental status, hypothermia, autonomic instability, Rx with Dantrolene or DA agonists.
Ex: Haloperidol, Fluphenazine.
__azine
Typical Antipsychotic Agents. Low potency.
Blocks postsynaptic D2 receptors in limbic system, decreasing response to DA excitation. Some inhibition at H1, cholinergic, and a-adrenergic receptors, leads to side effects.
Rx positive symptoms of schizophrenia (delusions, hallucinations), Tourettes, delirium, agitation. SE: sedation (H), anticholinergic effects, orthostatic hypotension (a), extrapyramidal signs (dystonia, akinesia, akathisia, tardative dyskinesia) from DA blockade, increased prolactin (galactorrhea, amenorrhea) from lack of DA inhibition of pituitary.
Neuroleptic malignant syndrome: muscle rigidity, altered mental status, hypothermia, autonomic instability, Rx with Dantrolene or DA agonists.
Ex: Chlorpromazine, Thioridazine.
__apine, __idone
Atypical Antipsychotic Agents.
Blocks Serotonin (5HT2) and DA receptors in limbic system, decreasing response to DA and Serotonin. Some inhibition in H1, Cholinergic, a-adrenergic receptors, but much less than the typicals.
Rx positive and negative symptoms of schizophrenia, bipolar, other psychotic disorders. O, R, Q Rx for delirium. SE: Drowsiness, mild weight gain, mild hypotension, Parkinsonism symptoms. Clozapine causes mild leukopenia and agranulocytosis. Fewer side effects than the typicals.
Ex: Clozapine, Risperidone, Olanzapine, Ziprasidone, Aripriprazole, Quetiapine.
__azepam, __zolam
Benzodiazepines. Sedative.
Bind adjacent to GABAa receptor and enhance activity, resulting in increased frequency of Cl- flow, leading to cell membrane hyperpolarization and ultimately decreased activity of the neurons of the limbic, thalamic, and hypothalamic regions of the CNS.
Rx anxiety, seizures, status epilepticus, muscle spasms, EtOH withdrawl, insomnia, panic disorder. Mida and Diaz also anesthetics. Dependence potential. SE: sedation, altered mental status, ataxia. Withdrawl: altered mental status, anxiety, tachycardia, vomiting. Overdose: cardiac and respiratory depression, Rx with Flumazenil (competitive antagonist at GABA).
Less dangerous than Barbiturates. Avoid in patients with liver disease, alcohol use, Barbituates, or other CNS depressants.
Ex: Short - Triazolam, Midazolam. Intermediate - Lorazepam, Temazepam, Oxazepam, Alprazolam. Long - Diazepam, Prazepam, Clonazepam, Flurazepam.
Flumazenil
CNS Agent.
Competative agonist for GABAa receptors.
Rx for Benzodiazepine overdose treatment along with supportive care. Benzo overdose: cardiac and respiratory depression.
__bartital
Bartiburates. Sedative.
Indirectly potentiate GABAa receptor activity in brain, increasing time Cl- open, leading to cell membrane hyperpolarization and decreased CNS neuronal activity.
Rx of anxiety, insomnia, anesthesia induction (Thio), seizure management and neonatal hyperbilirubinemia (Pheno). SE: Sedation, nausea, teratogen. Dependence potential. Withdrawal: nausea, anxiety, seizures, tachycardia. Overdose: cardiac and respiratory depression, Rx with ventilation, hemodialysis, alkalinization of urine.
More dangerous than Benzodiazepines. Avoid in liver disease, pregnancy, porphyria, alcohol, benzos, other CNS depressants. Induces P-450.
Ex: Phenobarbital, Thiopental, Secobarbital, Amobarbital, Pentobarbital.
Phenytoin
Anti-Epileptic
Decreases Na+ and Ca++ flow, leading in decreased depolarization of NS cells.
Rx for simple and complex partial seizures, grand maul seizures (generalized tonic-clonic), status epilepticus, trigeminal neuralgia, torsades de pointes.
SE: Nystagmus, diplopia, gait instability, gingival hyperplasia, hirsutism, neuropathy, megaloblastic anemia, rash, drug-induced lupus, teratogen (fetal hydantoin syndrome - prenatal growth deficiency, congenital cardiac and palate malformations). Induces P-450.
Lamotrigine
Anti-Epileptic
Inhibits Na+ channels and release of glutamate from nervous tissue.
Rx for simple and complex partial seizures, generalized tonic-clonic seizures. SE: severe rash, nausea, headache.
Valproic Acid
Anti-Epileptic
Increase GABA concentrations by inhibiting metabolizing enzymes and hyperpolarization of membrane via change in Na+/K+ conductance.
Rx in generalized tonic-clonic seizures, myocloni seizures, absence seizures, mania in bipolar, prevention of migraines. SE: hepatotoxicity, thrombocytopenia, teratogen (neural tube defects), GI upset, sedation, nausea, weight gain.
Ethosuximide
Anti-Epileptic
Decreases Ca++ current across cell and inhibits GABA metabolism.
Rx of absence seizures.
__azepine
Anti-Epileptic
Inhibits flow of Na+ , causing neural cell hyperpolarization and decreased neuronal activity.
Rx for simple and complex partial seizures, generalized tonic-clonic seizures, trigeminal neuralgia. SE: GI upset, diplopia, dizziness, hepatotoxicity, agranulocytosis, aplastic anemia. Induces P-450.
Ex: Carbamazepine, Oxocarbazepine.
Topiramate
Anti-Epileptic
Inhibits flow of Na+ , causing neural cell hyperpolarization and decreased neuronal activity.
Adjunct Rx for simple and complex partial seizures.
Tiagabine
Anti-Epileptic
Inhibits reuptake of GABA and potentiates its effects.
Rx of partial seizures with other drugs. SE: GI upset, sedation, tremor, ataxia.
Vigabatrin
Anti-Epileptic
Inhibits breakdown of GABA.
Rx of partial seizures. SE: sedation, psychiatric disturbances.
Levetiracetam
Anti-Epileptic
Adjunctive Rx for epilepsy and neuropathic pain. Unknown MOA.
Succinylcholine
Anesthetic Agent
Competes with ACh to reversibly bind N receptors at NMJ, causing depolarizing neuromuscular block.
Phase 1: Constant stimulation/depolarization leads to muscle fasiculations (irreversible with AChEI drugs).
Phase 2: Channels associated with N receptor begin to repolarize, but are desensitized, so will no longer transmit AP even if receptor activated. Muscle paralysis. Reversible with cholinesterase inhibitor such as Physostigmine.
Used to produce muscle paralysis for intubation during surgery or emergencies. SE: hyperkalemia, nausea, vomiting, muscle soreness, apnea, arrhythmia, bradycardia.
NEVER give with Haloethane, malignant hyperthermia results. Muscle rigidity, fever, Rx is Dantrolene.
Dantrolene
Inhibits release of Ca++ from SR of myocytes, decreasing muscle contraction.
Rx for malignant hyperthermia (muscle rigidity, fever) from Halothethane and Succinylchole administration.
__curonium, __curium
Anesthetic Agent
Competitively binds N receptors at NMJ, leading to nondepolarizing neuromuscular block. Prevents ACh from binding and activating these receptors, resulting in inhibited muscle contraction. Curare.
Used as an adjunct to general anesthesia induction to reduce skeletal muscle contraction to facilitate intubation. SE: hypotension, tachycardia, prolonged respiratory depression. Reverse with an AChEI, raising ACh levels to overcome the competitive binding.
Ex: Pancuronium, Vecuronium, Atracurium, Cisatracurium, Tubocurarine, Mivacurium, Rapacuronium.
__caine
Local Anesthetic Agents
Membrane stabilizing by blocking Na+ influx, decreasing activation and leading to fewer APs. Blockade most rapid in small myelinated fibers. Often given with vasoconstrictor (EPI) locally to contain the anesthetic.
Used in minor surgical procedures to block a local area. SE: seizures, neurotoxicity, myocardial depression and hypotension (Bupivacaine), hypertension and arrhythmia (Cocaine).
Ex: Esters (short) - Procaine, Cocaine, Tetracaine, Benzocaine. Amides (longer)- Lidocaine, Bupivacaine.
__ane
General Inhaled Anesthetic Agents
MOA poorly understood, may directly activate GABAa receptors in brain, leading to decreased neuronal activity.
Used for general anesthetic induction and maintenance. SE: myocardial and resiratory depression, GI upset, increased cerebral blood flow. Halo - fulminant hepatic necrosis, hypotension, arrhythmias. Methoxy and Enflur - nephrotoxic and seizures.
DO NOT give Haloethane with Succinylcholine, malignant hyperthermia may result (muscle rigidity and fever), Rx with Dantrolene.
Ex: Desflurane, Isoflurane, Sevoflurane, Halothane, Enflurane, Methoxyflurane.
Propofol, Etomidate, Ketamine
General Intravenous Anesthetic Agents
Propofol: prolongs GABAa activity. Used for induction and maintenance of anesthesia and conscious sedation. SE: hypotension, pancreatitis.
Etomidate: prolongs GABAa activity. Used for induction of anesthesia and conscious sedation. SE: vomiting, myoclonus, adrenal suppression.
Ketamine: NDMA receptor antagonist, decreasing neuronal conduction. Rarely used due to side effects, used locally for neuropathic pain. SE: hallucinations, cardiac and repiratory depression.
Others: Benzodiazepines, Barbiturates, Opioids
__morph__, __codone
Opioids. Anesthetic Agents.
Bind and activate specific opioid receptors throughout NS (brainstem, SC, peripheral nerves, amygdala, hypo/thalamus). Results in hyperpolarization and decreased activity of neural cells via Ca++ and K+ channels.
Used for pain control, cough suppression (brainstem - Codeine, Dextromethorphan), diarrhea (Diphenoxylate), acute pulmonary edema (morphine). SE: nausea, cardiac and respiratory depression, constipation, miosis. Dependence and tolerance potential. Withdrawal: severe GI upset, anxiety, chills. Methadone eases symptoms without a high. Treat overdose with Naloxone and Naltrexone.
Ex: Morphine, Codine, Oxycodone, Hydrocodone, Hydromorphone, Heroin, Meperidine, Fentanyl, Dextromethorphan.
Naloxone, Naltrexone
Opioid receptor antagonists.
Treat opioid overdoses. Methadone eases the symptoms of withdrawl without the high.
Levidopa/Carbidopa
CNS Agent
Converted to DA in brain by DOPA-decarboxylase, increasing DA levels in CNS.
First-line treatment for Parkinsonism (loss of dopaminergic neurons in the basal ganglia). SE: Dyskinesia, sporatic movements, arrhythmias (peripheral conversion to DA), nausea, vomiting, hallucinations, depression.
Administer with Carbidopa, which inhibits peripheral DOPA-decarboxylase (doesnt cross BBB), prevents side effects, and increases bioavailability of Levodopa in brain.
__triptan
CNS Agent
Stimulates presynaptic 5-HT 1D receptors, resulting in inhibited vasodilation and inflammation of dura, and 1B resulting in vasoconstriction of intracranial vessels.
Acute Rx for migraines and cluster HA. SE: coronary vasospasm with chest pain, dizziness. Contraindicated in CAD.
Ex: Sumatriptan, Rizatriptan, Naratriptan, Zolmitriptan.
Buproprion, Varenicline
Smoking Cessation Agents. Nicotinic Receptor Antagonists.
Bupropion: inhibits NE/DA reuptake, Nicotinic antagonist. Rx: smoking cessation and antidepressant. SE: psychosis, seizures, dry mouth.
Varenicline: partial agonist and antagonist at aB Nicotinic ACh receptors in brain. Rx: smoking cessation. SE: nausea, insomnia, suicidal ideation. Partial N agonist makes withdrawl and cravings less.
By binding Nicotinic receptors, nicotine from smoking cannot stimulate the mesolimbic dopamine system, interfering with the reinforcement/reward loop of smoking.
Buspirone
Serotonin Partial Agonist
Partially activates 5-HT 1A presynaptic receptor, and mixed agonist/antagonist activity on postsynaptic DA receptors in brain.
Rx of GAD, used in conjunction with SSRIs in depression. SE: dizziness insomnia, nausea.
Gabapentin
CNS Agent
MOA unknown. GABA analogue that may interact with Ca++ channels in CNA, resulting in decreased Glutamate and NE release.
Rx of postherpetic neuralgia, chronic neuropathic pain, and partial seizures. SE: Peripheral edema, sedation, hepatotoxicity.
Pregabalin: same MOA, used to treat neuropathic pain (especially diabetic neuropathy and postherpetic neuralgia), partial seizures, and fibromyalgia
