Pharm Drug Categories:Mechanisms of Action PDF

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Exam 1 Summaries over chapters in book...

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Mechanisms of Action (MOA) Ch.10: Analgesic Drugs Opioid agonist: agonist at opioid pain receptor site. Create an analgesic effect -Adverse effects: -Codeine: -opioids also suppress the medullary cough center; which results in cough suppression. Most commonly used opioid for this -Fentanyl: -used most commonly in perioperative settings and ICU settings for sedation during mechanical ventilation. Very potent -Hydromorphone: -seven times more potent than morphine -Meperidine: -used with caution in older adults. Can accumulate to toxic levels and lead to seizures -Methadone: -choice for detoxification treatment of opioid addicts -Morphine: -prototype for all opioid drugs -Oxycodone: opioid agonist Opioid antagonists: MOA- compete with opioids at CNS receptor sites -Naloxone: -has no agonistic morphine-like properties, blocks opioid drugs. Drug of choice for reversal of opioid induced respiratory depression Nonopioid and miscellaneous analgesics: MOA- varies -Acetaminophen: -MOA: blocks peripheral pain impulses by inhibition of prostaglandin synthesis -Tramadol: -indicated for mild to moderate pain, similar adverse effect to those of opioids -Lidocaine: -topical anesthetic; patch placed on painful areas of the skin

Ch.11: General and Local Anesthetics General anesthetics: MOA- varies -Dexmedetomidine: alpha2 adrenergic receptor agonist -produces dose-dependent sedation, decreased anxiety, and provides analgesia without respiratory depression. Also used commonly in ICU for sedation of mechanically ventilated patients

-Ketamine: -MOA: binds to receptors of CNS and PNS, opioid receptors, and NMDA receptors -used for both general anesthesia and moderate sedation. Commonly used in emergency department for setting broken bones. Rapid onset of action. Adverse effects include hallucinations -Nitrous oxide: -Inhaled. Primarily used for dental procedures, often administered in addition to other commonly used inhaled agents -Propofol: -used for induction and maintenance of general anesthesia and also sedation during mechanical ventilation in ICU -Sevoflurane: -inhaled. Rapid onset and elimination making them especially useful in surgical settings commands

Local anesthetics: MOA- varies. Works by rendering a specific portion of the body insensitive to pain. Blocks generation and conduction of impulses in nerve fibers -Lidocaine: -amide local anesthetic Neuromuscular Blocking Drugs (NMBDs) (local anesthetic): Bind to Ach receptors at neuromuscular junction -Succinycholine: -Depolarizing: Competitive agonist -Rocuonium: -Nondepolarizing: Competitive antagonist -commonly used to facilitate endotracheal intubation, reduce muscle contraction, and facilitate a variety of diagnostic procedures

Ch.12: Central Nervous System Depressants and Muscle Relaxants Benzodiazepines: MOA- not certain thought to be either GABA receptors or adjacent receptors. Depress activity in the CNS -Diazepam (Valium): -prototypical benzodiazepine -Midazolam: -most commonly used preoperatively and for moderate sedation -Temazepam: -has been replaced by newer drugs Nonbenzodiazepines: MOA- varies -Eszopiclone (Lunesta):

-designed to provide a full 8 hours of sleep -Ramelton: -structurally similar to melatonin. Used for sleep onset -Zolpidem (Ambien): -possibility of sleepwalking Orexin Receptor Antagonists: bind to orexin receptors -regulate transitions between wakefulness and sleep by promoting cholinergic/monoaminergic pathways -Suvorexant Barbiturates: CNS depressants that act in the brainstem. Reduce nerve impulses traveling to the cerebral cortex -Pentobarbital: -used preoperatively to relieve anxiety and provide sedation -Phenobarbital: -prototypical barbiturate. Used for generalized tonic-clonic seizures and fever-induced convulsions

Muscle Relaxants: work within the CNS -Baclofen -Cyclobenzaprine: -most commonly used drug in this class to reduce spasms following musculoskeletal injuries

Ch.13: Central Nervous System Stimulants and Related Drugs ADHD Drugs & Narcolepsy: -Amphetamines -Atomexetine: -lack addictive properties unlike amphetamines -Methyphenidate (Ritalin): -first prescription drug indicated for ADHD -Modafinil (Provigil): -indicated for wakefulness in patients with excessive daytime sleepiness associated with narcolepsy

Anorexiant: -Phentermine -Orlistat: -Alli is an OTC version. Works by binding to gastric and pancreatic enzymes called lipases. Blocking these enzymes reduces fat absorption by approximately 30%

Antimigraine Drugs: Serotonin receptor agonists. Triptan stimulate these receptors in cerebral arteries causing vasoconstriction and reducing headache symptoms -Sumatriptan -prototype drug for this class

Central Nervous System Stimulants (Commonly Used for Respiratory Depression): -Caffeine -Doxapram: -used in conjunction with supportive measures in cases of respiratory depression that involve anesthetics or drugs of abuse

Ch.14: Antiepileptic Drugs -Phenobarbital and Primidone: -barbiturates -Phenytoin and Fosphenytoin: -Phenytoin has been a first-line drug for years and is prototypical drug for epilepsy. Indicated for the management of tonic-clonic seizures and partial seizures -Fosphenytoin is injectable prodrug of phenytoin -Carbmazepine: -second most commonly prescribed antiepileptic drug -Oxcarbazepine -Ethosuximide -Gabapentin -chemical analogue of GABA that inhibits brain activity -Lamotrigine -Levetiracetam -Pregabalin: -structurally related to GABA -Tigabine -Topiramate -Valproic acid -Zonisamide

Ch.15: Antiparkison Drugs Monoamine Oxidase Inhibitors (MAOIs): Enzyme Monoamine Oxidase causes the breakdown of catecholamines in the body. MAO Inhibitors increase levels of dopaminergic stimulation in CNS -Rasagiline and Selegiline:

-selective MAO-B inhibitors Dopamine Modulator: Release dopamine and other catecholamines from their storage sites in the presynaptic fibers of nerve cells. Also blocks the reuptake of dopamine in to nerve fibers. Results in higher levels of dopamine in the synapses -Amantadine Catechol Ortho-Methyltransferase (COMT) Inhibitors: Block COMT. COMT is the enzyme that catalyzes the breakdown of the body’s catecholamines -Entacapone: -indicated for adjunctive treatment with levodopa (prolonging duration of action of levodopa) Nondopamine Dopamine Receptor Agonists: Work by direct stimulation of presynaptic and/or postsynaptic dopamine receptors in the brain. Stimulate production of more dopamine -Bromocriptine: -Stimulates only the D 2 receptors and antagonizes D1 receptors -Pramipexole Dopamine Replacement Drugs: Stimulate presynaptic dopamine receptors to increase brain levels of dopamine -Carbidopa-levodopa: -levodopa is precursor of dopamine. Significantly metabolized before it reaches the brain, so it is combined with carbidopa. Carbidopa allows for much lower doses of levodopa to be used Anticholinergic Drugs: Block the effects of the neurotransmitter acetylcholine at cholinergic receptors in the brain as well as rest of the body -Benzotropine mesylate

Ch.16: Psychotherapeutic Drugs Anxiolytic Drugs: Benzodiazepines: -Alprazolam (Xanax): -most commonly used. Short term relief -Diazepam (Valium) -Lorazepam (Ativan): -intermediate-acting Miscellaneous Drug: -Buspirone: -MOA unknown, appears to be agonist at both serotonin and dopamine receptors Mood Stabilizing Drugs: used for treating bipolar illness

-Lithium: -levels required to produce a therapeutic effect are close to toxic levels

Antidepressant Drugs: increase the levels of neurotransmitter concentrations in the CNS (serotonin, dopamine, norepinephrine) Tricyclic Antidepressants: work by correcting imbalance in the neurotransmitter concentrations. First generation anti-depressants, less used today -Amitriptyline Monoamine Oxidase Inhibitors (MAOIs): -Selegiline transdermal patch

Second-Generation Antidepressant Drugs: -Bupropion (Wellbutrin): -therapeutic activity appears to be primarily dopaminergic and noradrenergic. Used for treatment of depression and smoking cessation -Citalopram: -SSRI (Selective Serotonin Reuptake Inhibitor) -Duloxetine: -SSNRI (Selective Serotonin-Norepinephrine Reuptake Inhibitor) -Fluoxetine (Prozac): -first SSRI marketed and prototypical SSRI -Mirtazapine: -promotes the synaptic release of serotonin, due to antagonist activity in the presynaptic alpha adrenergic receptors. Does not inhibit reuptake -Trazodone: -SSRI

Antipsychotic Drugs: block dopamine receptors in the brain, which decreases the dopamine concentration in the CNS -Haloperidol: indicated primarily for the long-term treatment of psychosis Atypical Antipsychotics: -Aripiprazole: -indicated for schizophrenia, bipolar disorder, major depression disorder -Clozapine -Risperidone

Ch.44: Antiinflammatory and Antigout Drugs

Nonsteroidal Antiinflammatory Drugs: MOA- inhibition of the leukotriene pathway, the prostaglandin pathway, or both -Aspirin: -prototype salicylate -Indomethacin: -used in treatment of rheumatoid arthritis, osteoarthritis, tendonitis -Ketorolac (Toradol) -Ibuprofen: -prototype NSAID in pionic acid category -Celecoxib (Celebrex): -COX-2 inhibitor

Antigout Drugs -Allopurinol: -inhibits the enzyme xanthine oxidase which thereby prevents uric acid production -Colchicine -Lesinurad -uric acid transporter inhibitor, inhibits transporter proteins involved in renal uric acid reabsorption and thus lowers serum uric acid levels -Probenecid: -inhibits the reabsorption of uric acid in kidney...