Exam 3 Flashcards
Dopamine, epinephrine, norepinephrine, and serotonin are all what?
monoamines (NT of the CNS)
Aspartate, GABA, Glutamate, and Glycine are all what?
amino acid (NT of the CNS)
Adenosine, adenosine monophosphate, and adenosine triphosphate are all what?
purines (NT of the CNS)
Dynorphins, endorphins, and enkephalins are all what?
opioid peptides (NT of the CNS)
Neurotensin, oxytocin, somatostatin, substance P, and vasopressin are all what?
nonopioid peptides (NT of the CNS)
Name two “other” neurotransmitters of the CNS?
Acetylcholine, Histamine
Which will pass through the blood brain barrier easier, lipid soluble molecules or charged/protein bound molecules and why?
lipid soluble because of the tight junctions that make up the BBB.
What are some possible adaptations of the CNS to prolonged drug exposure?
increased therapeutic effects due to adaptive changes (antipsychotics and antidepressants), decreased side effects (phenobarbital and sedation, morphine and nausea), tolerance and physical dependence
Dyskinesias such as tremor at rest, rigidity, postural instability, gait issues, bradykinesia, akinesia, autonomic disturbances, depression, psychosis, and dementia are all symptoms of what neurodegenerative disorder?
Parkinson’s Disease
Describe the pathology and cause of Parkinson’s Disease?
There is a degeneration of the neurons that supply dopamine to the striatum causing an imbalance between dopamine and acetylcholine. Excess ACh promotes GABA transmission to the globus pallidus and causes excess movement.
Recent evidence suggests which three proteins play a role in Parkinson’s Disease? Which one is toxic to dopaminergic neurons?
alpha-synuclein is the one that is toxic to dopaminergic neurons. Parkin and ubiquitin are the two proteins that are involved in breaking down alpha-synuclein. If any of these three proteins are defective then alpha-synuclein accumulates in the cell forming neurotoxic fibrils called lewy bodies.
What are the two major categories of drugs used to treat Parkinson’s disease?
dopaminergic agents and anticholinergic agents
This dopaminergic agent is used to treat PD and promotes dopamine synthesis, often given in combination with carbidopa.
levodopa
These dopaminergic agents stimulate dopamine receptors directly, examples include Pramipexal (Mirapax) and Apomorphine.
dopamine agonists
This dopaminergic agent inhibits dopamine breakdown, Selegine (Eldepryl and Carbex) are examples.
MAO-B inhibitor
This dopaminergic agent promotes dopamine release.
Amantadine
These dopaminergic agents block the degradation of levadopa, an example is Entacapone (Comtan).
COMT inhibitors
This drug used for PD crosses the blood brain barrier and is then converted to dopamine by the enzyme decarboxylase pyridone. It can be degraded in the brain, liver, and intestine.
Levodopa
Nausea and vomiting due to the presence of DA-R in the CTZ, Dyskinesia, dysrhythmias, hypotension, psychosis in 20% of patients, dark urine and sweat, malignant melanoma, and the need for drug holidays are all adverse reactions of which PD med?
Levodopa
Why are Carbidopa and Levodopa often given together and what are the advantages and disadvantages of this?
The Carbidopa prevents decarboxylation of Levodopa in the periphery, making more of it available in the brain. this decreases the amount of levodopa needed for a therapeutic response. The disadvantage is that abnormal movements and psychiatric disturbances appear sooner.
How do Carbidopa, Tolcapone, and Entacapone increase the effects of Levadopa?
By inhibiting its metabolism.
How do Bromocriptine and Pramipexole increase the effects of Levadopa?
By directly stimulating dopamine receptors.
How does Amantadine increase the effects of Levadopa?
By promoting the release of dopamine.
How do anticholinergic drugs increase the effects of Levadopa?
By blocking CNS acetylcholine receptors.
Name 2 drugs that decrease the effects of Levadopa?
vitamin B6 which enhances its destruction by decarboxylases, and antipsychotics which block CNS dopamine receptors.
Name a class of drugs that increase Levodopa toxicity.
MAO inhibitors can cause a hypertensive crisis when combined with Levodopa.
What are the effects of high protein meals on Levodopa?
It decreases the absorption of Levodopa because the amino acids compete for absorption in the brain and intestine.
This non ergot derivative dopamine agonist can be used alone in early PD treatment, and with Levodopa in late stage treatment. It is also approved for restless legs syndrome. Side effects include “sleepy attacks”, nausea, dizziness and insomnia.
Pramipexole (Mirapex)
This COMT inhibitor is used with levadopa and prolongs the halflife of the drug. It is a reversible drug that inhibits levodopa metabolism in the periphery. Adverse effects are due to levodopa levels and include hallucinations, dyskinesias, nausea, and hypotension.
Entacapone (Comtan)
Another COMT inhibitor that functions similar to Entacapone. It has more serious adverse effects including liver failure, dyskinesias, and nausea.
Tolcapone (Tasmar)
This drug used in treating PD possibly increases dopamine release, decreases dopamine reuptake, creates cholinergic blockade and glutamate receptor blockade. It has less of a response than levodopa but is the drug of choice for dyskinesias. This drug is a second line treatment. Adverse effects include CNS effects and peripheral effects due to muscarinic block, also, livedo reticularis (skin discoloration).
Amantadine (Symmetrel)
This irreversible MAO-B inhibitor is used to treat PD. It is a second or third line treatment that inhibits MAO-B in the striatum and may delay the disease. May be used alone or with levodopa. May have interactions with various drugs like meperidine and fluoxetine and can be fatal.
Selegiline (Eldepryl, Carbex)
These two anticholinergic agents are a second line treatment for PD and addresses tremors. They are more commonly used in younger patients with mild symptoms. These drugs work by blocking muscarinic receptors in the striatum. Side effects include delusion, confusion, and hallucinations (CNS effects). If they block receptors in the periphery they can cause dry mouth, blurred vision, photophobia, urinary retention, constipation and tachycardia.
Trihexyphenidyl (Artane) and Benztropine (Cogentin)
What are the two major risk factors for Alzheimer’s disease?
advancing age and family history
Being female, have a head injury, low educational level, production of apoE4, high levels of homocysteine, and nicotine in cigarette smoke are all possible risk factors for which disease?
Alzheimer’s Disease
Thia disease involves the degeneration of neurons in the hippocampus first and then the cerebral cortex. There is reduced cholinergic transmission and the formation of beta-amyloid and neuritic plaques. Neurofibrillary tangles and tau protein are also present. Apolipoprotein E4 (ApoE4) binds to beta amyloid and renders it insoluble. Endoplasmic Reticulum-associated binding protein (ERAB) enhances neurotoxicity to beta amyloid. Elevation of homocysteine also blocks neural blood vessels.
Alzheimer’s Disease
Symptoms of this disease include memory loss, confusion, disorientation, impaired judgment, personality changes, difficulty with self-care, behavior problems such as wandering, pacing, agitation, screaming - sun downing, an inability to recognize family members, and an inability to communicate.
Alzheimer’s Disease
This classification of drugs is used to treat Alzheimer’s Disease and prevents the breakdown of Acetylcholine and helps to slow the progression of the disease. Adverse effects include cholinergic side effects, GI issues, dizziness, headache, bronchoconstriction, and liver injury.
Cholinesterase inhibitors
This reversible cholinesterase inhibitor is rarely used due to the fact that it is hepatotoxic. It has a short half life and requires dosing 4 times a day.
Tacrine (Cognex)
This reversible cholinesterase inhibitor is selective to acting on cholinesterase in the brain. It has a 60 hour half life and requires once a day dosing. It is the drug of choice for Alzheimer’s Disease.
Doneprazil (Aricept)
This “irreversible” cholinesterase inhibitor has modest benefits and no significant drug interactions.
Rivastigamine (Excelon)
This reversible cholinesterase inhibitor is used for mild to moderate Alzheimer’s Disease. It can cause GI complaints.
Galantamine (Reminyl or Razadine)
This drug is an NMDA receptor antagonist used to treat Alzheimer’s Disease. It is indicated for moderate to severe AD and is better tolerated than cholinesterase inhibitors. Adverse effects include dizziness, headache, confusion, and constipation. When combined with doneprazil there is less of a decline in cognitive and day to day function.
Memantine (Namenda)
Name the 2 atypical antipsychotics and the SSRI that are used to treat neuropsychiatric symptoms associated with Alzheimer’s disease.
Risperidone (Risperdal), Olanzapine (Zyprexa), and Prozac
This disease is a chronic, inflammatory autoimmune disorder that attacks the myelin sheath of neurons in the CNS. It causes a wide variety of motor and sensory deficits. Symptoms usually grow progressively worse and the patients may experience periods or complete or partial recovery or remission. It is more common in countries with cold climates and Caucasians of Northern Europe descent are at high risk.
Multiple Sclerosis
This type of MS is recurrent with partial or full recovery. 80-90% of patients have this type initially.
relapsing-remitting MS
This type of MS is steady, worsening with minor remissions. 50% of patients have this version within 10-20 years.
secondary progressive MS
This type of MS affects 10% of patients and clear remissions doesn’t occur.
primary progressive MS
This is the rarest type of MS.
progressive-relapsing MS
These drugs are all used to treat MS and are given via injection. Their MOA is unknown but they reduce the frequency and severity of attacks and the number and size of lesions. They delay the progression of disability of MS. Adverse effects include flu-like reactions, hepatotoxicity (increase in liver enzymes), myelosuppression, injection site reactions, depression.
interferon beta
These two interferon beta drugs are injected subQ and have more benefit than Avonex.
Rebif and Betaseron
This drug is used for long term therapy of relapsing-remitting MS. It is a polypeptide referred to as copolymer-1. It inhibits immune response to myelin basic protein. This drug promotes T cell shift (TH2>TH1). It increases inflammatory cells and inhibits inflammatory attack on myelin sheath. This drug is well tolerated but adverse effects include injection site reactions and post injection reactions such as flushing, palpitations, severe chest pain, anxiety, laryngeal constriction, and urticaria in 10% of people.
Glatiramer Acetate (Copaxone)
This MS medication was approved in 2004 and then withdrawn from the market due to progressive multifocal leukoencephalopathy before being reintroduced in 2006. It is used for relapsing forms of MS and Crohn’s disease. It acts by preventing activated leukocytes from crossing the blood brain barrier. Leukocytes must bind to vascular endothelium before they exit the blood vessels. This drug binds to integrin molecules on leukocytes and prevents binding and thus stops them from leaving the blood vessels. Adverse reactions include hepatotoxicity, hypersensitivity, and neutralizing antibodies.
Natalizumab (Tysabri)
This MS drug is the first oral disease modifying drug. It is more effective than interferon beta but has more adverse effects. It’s MOA is that is binds to SIP receptors and sequesters lymphocytes in lymph nodes. Fewer lymphocytes in blood then less enter the brain thus less inflammation and less nerve damage. Adverse effects include bradycardia, macular edema, liver injury and reduced lung function and fetal harm.
Fingolimod (Gilneya)
This immunosuppressant is more toxic than immunomodulators and is used to decrease neurologic disability and clinical relapses, and to treat worsening relapsing-remitting MS, secondary progressive MS, and progressive-relapsing MS. It works by suppressing production of T and B cells and reducing cytokine production. Adverse effects include myelosuppression, cardiotoxicity, fetal harm, also it is toxic to any tissues with rapidly producing cells like bone marrow and hair follicles. Also tints urine a blue green color.
Mitoxantrone
This type of seizure begins focally in the cerebral cortex and has a limited spread to adjacent cortical areas.
partial (focus) seizures
This type of seizure lasts 20-60 seconds and involves no loss of consciousness.
simple partial seizure
This type of seizure lasts 45-90 seconds and involves the person becoming partially unresponsive and automatism.
complex partial seizure
This type of seizure lasts 1-2 minutes and is a mix of simple and complex.
secondarily generalized seizure
This type of seizure can be convulsive or nonconvulsive and effects both hemispheres with immediate loss of consciousness.
generalized seizures
This type of seizure has a loss of consciousness of 10-30 seconds and can occur almost 100 times a day. It is usually seen in children.
absence/petit mal seizure
This type of seizure involves a loss of muscle tone and is seen in children. The head may drop and the person might collapse.
atonic seizure
This type of seizure involves muscle contractions that last about a second. It can be one limb or the entire body.
myoclonic seizure