Unit 2

• Schizophrenia symptoms:

  • Positive symptoms: hallucinations, delusions, confused thoughts/disorganized speech, movement disorders
  • Negative symptoms: lack of pleasure, trouble with speech, flattening, withdrawal from others, struggle with daily life, unable to finish tasks
  • Antipsychotics work better on positive symptoms vs negative symptoms
• Antipsychotics:

  • 1st generation (conventional or "typical"): Haloperidol, loxapine, chlorpromazine, methotrimeprazine
  • Block dopamine in ALL pathways in the brain
  • Block muscarinic, Alpha1 receptors, and histamine1 receptors (leading to more side effects)
  • 2nd generation (atypicals): Clozapine, risperidone, olanzapine, quetiapine, lurasidone
  • Block dopamine in the mesolimbic pathway in the brain
  • Block certain 5-HT receptors (lower risk of extrapyramidal symptoms)
• Side effects of Antipsychotics:

  • Extrapyramidal symptoms (EPS), Pseudo-Parkinsonism, Akathisia, Tardive Dyskinesia (TD), Anticholinergic effects, Dystonia, Hyperprolactemia, Seizures, Weight gain, Neuroleptic Malignant Syndrome
• Depression symptoms:

  • Sadness, self-loathing, loss of interest and focus, irritability and isolation, anxiety, loss of energy, disturbed sleep, change in appetite, reckless behavior, suicidal thoughts
• Types of depression:

  • Major Depressive Disorder (MDD), Bipolar Disorder, Dysthymia (persistent depressive disorder)
• Antidepressants:

  • SSRIs (Selective serotonin reuptake inhibitors): citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline
  • SNRIs (Serotonin and norepinephrine reuptake inhibitors): venlafaxine, desvenlafaxine, duloxetine, levomilnacipran
  • TCAs (Tricyclic antidepressants): amitriptyline, clomipramine, nortriptyline, doxepin, imipramine, desipramine
  • MAOIs (Monoamine Oxidase Inhibitors): irreversible or reversible, interact with other meds, dietary restrictions
• Bipolar Disorder:

  • Bipolar I: at least 1 episode of mania, depression episodes usually occur
  • Bipolar II: cycling between hypomania and depression
  • Treatment: mood stabilizers (lithium), anticonvulsants, antipsychotics, antidepressants
• Lithium:

  • Used to treat mania in Bipolar Disorder
  • Increases GABA and decreases glutamate
  • Narrow therapeutic index, early signs of toxicity: fatigue, muscle weakness, drowsiness, tremors, vomiting, diarrhea
  • Decreases sodium reabsorption in renal tubules, patients need to stay hydrated and maintain consistent sodium intake
• Parkinson's Disease is a progressive, degenerative disorder characterized by bradykinesia, rigidity, resting tremor, and postural instability
• Parkinson's Disease involves the degeneration of dopaminergic neurons in the substantia nigra, where dopamine controls movement
• Medication for Parkinson's aims to control symptoms as there is no cure, and it must be taken on time to avoid symptoms appearing as the medication wears off
• Common side effects of Parkinson's medication include nausea, hypotension, behavioral changes, and sudden drowsiness
• Drug therapy for Parkinson's aims to restore the balance between acetylcholine (Ach) and dopamine, with dopaminergic drugs like Levodopa/Carbidopa being the drug of choice
• Dopaminergic drugs increase dopamine levels in the brain to help with motor complications in Parkinson's Disease
• Dopamine agonists mimic the action of dopamine in the brain by stimulating receptors, examples include Pramipexole, Ropinirole, Bromocriptine, and Cabergoline
• COMT inhibitors (Entacapone) and MAO-B Inhibitors (Selegiline, Rasagiline) block different enzymes that break down Levodopa, allowing Levodopa to work better
• Anticholinergic drugs aim to decrease levels of Ach to help with tremor and decrease drooling in Parkinson's Disease, examples include Trihexyphenidyl and Benztropine
• Alzheimer's Disease is a chronic neurodegenerative disease that destroys brain cells, leading to brain atrophy seen in MRI imaging
• Alzheimer's Disease is not a normal part of aging, is not reversible, and is the most common type of dementia, accounting for 60-80% of all cases
• The cause of Alzheimer's Disease is still unknown but is thought to be related to the development of plaques and tangles in the brain
• Plaques are dense clusters of amyloid protein that block signals between brain cells, leading to cognitive decline in Alzheimer's Disease
• Tangles in Alzheimer's Disease are caused by tau proteins collapsing and twisting, preventing nutrients from reaching other brain cells and leading to cell death
• Drug therapy for Alzheimer's includes Cholinesterase inhibitors like Donepezil, Galantamine, Rivastigmine, and NMDA Antagonist like Memantine
• Cholinesterase inhibitors decrease the breakdown of Ach to increase communication between nerve cells in Alzheimer's Disease
• NMDA Antagonist blocks the glutamate receptor to prevent the destruction of nerves involved in memory formation in Alzheimer's Disease
• Multiple Sclerosis is a chronic autoimmune disease of the CNS where the immune system attacks the myelin sheath covering the nerves, leading to damaged nerves and a lack of transmission of nerve impulses
• Drug therapy for Multiple Sclerosis includes Monoclonal antibodies, S1P modulators, fumarates, and antimetabolites, with the importance of starting medication ASAP after diagnosis
• Anxiety disorders include Panic Disorder, Social Anxiety Disorder, Generalized Anxiety Disorder, Post-traumatic Stress Disorder, and Obsessive-Compulsive Disorder
• The most evidence for treating anxiety disorders is with Cognitive Behavioral Therapy (CBT)
• Drug therapy for anxiety prefers SSRIs and SNRIs as antidepressants, with benzodiazepines being helpful for anxiety but not depression, to be used with caution due to the risk of abuse, dependence, sedation, and withdrawal
• Regular cannabis use is not recommended for anxiety as it may worsen symptoms, especially during withdrawal or between doses, and increase the risk of psychosis, mood disorders, and substance use disorders
• Anesthetics are used to reduce the sensation of pain:

  • Opiates and/or alcohol were commonly used for centuries
  • Surgical anesthesia began in the 1840s with Chloroform, Ether, and Nitrous oxide
  • Gaseous Anesthetics: Nitrous oxide (laughing gas), Diethyl ether, Chloroform (rarely used due to toxicity), newer halogenated hydrocarbons like halothane
• 3 types of Anesthetics:

  • Preanesthetic Medications: used prior to administration of an anesthetic to induce anesthesia, relieve anxiety/pain, and minimize side effects
  • General Anesthetics: Inhalation Anesthetics and Injectable General Anesthetics
  • Local Anesthetics: block the movement of Na+ into the neuron, indicated for minor surgery, vasectomy, suturing wounds, dental procedures, etc.
• Characteristics of Anesthesia:

  • 4 stages of Anesthesia: Stage I, Stage II, Stage III, Stage IV
• Seizures are characterized by hyperexcitability of brain neurons, usually brief, caused by various factors like high fever, certain meds, stroke, brain tumor, alcohol abuse, and classified by location in the brain and associated EEG patterns
• Types of Seizures:

  • Generalized Seizures: both sides of the brain affected, including Absence seizures (petit mal) and Tonic-clonic seizures (grand mal)
  • Partial (or Focal) Seizures: one area of the brain affected, including Simple seizures, Complex seizures, and Secondary generalized seizures
• Migraines affect ~10% of the population, more common in females, often accompanied by nausea and sensitivity to light & sound, important to identify triggers, and many patients experience an aura
• Drug Therapy for Migraines includes Triptans, NSAIDs, Anti-emetics, Beta-blockers, TCAs, Anticonvulsants, ACE inhibitors/ARBs, and SNRIs