Pharmacology For Neuromuscular Diseases Flashcards
Parkinson’s Disease symptoms occur when about ___% of the dopamine stored in the substantia nigra of the basal ganglia is depleted
80
PD worsesnw when too _____ dopamine is present and dyskinesia occurs when too _____ dopamine is present
Little; much
What is one of the mainstays of treatment for Parkinson’s Disease?
Levadopa-carbidopa
Antiparkinsonian drug therapies are aimed at
Increasing dopamine or antagonizing the effects of Ach
T or F: Antiparkinsonian drug therapy helps to slow the progression of the disease
FALSE; drug therapy may slow the progression of SYMPTOMS but not the disease itself
The variable response to levodopa, resulting in periods of good control and periods of poor control of PD symptoms
Off-on phenomenon
Classes of Antiparkinsonian drugs
Dopamine replacement drugs, MAOIs, dopamine modulator, COMT inhibitors, direct-acting dopamine receptor agonists, anticholinergic drugs
Carbidopa-levodpa indications
Treatment of some of the symptoms of PD
How to take carbidopa-levodopa (Sinemet)
Orally on an empty stomach
Carbidopa-levodopa (Sinemet) contraindication
Angle-closure glaucoma
Carbidopa-levodopa adverse effects
Cardiac dysrhythmias, hypotension, chorea, muscle cramps, GI distress
Early side effect of carbidopa-levodopa
N/V
Why is carbidopa given with levodopa?
Carbidopa does not cross the BBB and prevents levodopa breakdown in periphery. As a result, more levodopa crosses the BBB where it can be converted to dopamine; ALSO, levodopa causes extreme nausea when taken alone
Effects of dopamine replacement drugs such as levodopa therapy
Off-on phenomenon and wearing-off phenomenon
Can dopamine be given orally?
NO; this is why levodopa comes in a form that can be given orally and coverted to dopamine
Enzyme that causes the breakdown of catecholamines (like dopamine) in the body
Monoamine oxidase
_________ are used to improve the therapeutic effect of levodopa by preventing its breakdown
MAOIs
MAOI non-selective interact with
Tyramine-containing foods (cheese, dairy, red wine, chocolate, etc.)
List two examples of MAOIs used as monotherapy or as adjunct with levodopa for PD
Selegiline (Eldepryl) and rasagiline (Azilect)
MAOIs contraindications
Known drug allergy, concurrent use with meperidine (Demerol)
MAOIs adverse effects
Hypotension, confusion, dyskinesia, somnolence, LOTS of drug interactions (warfarin, cardiac drugs, antibiotics, etc.)
What is the only dopamine modulator for PD that is also an antiviral drug used for treatment of influenza?
Amantadine (Symmetrel)
Amantidine (Symmetrel) MOA
Blocks reputable of dopamine into the nerve fibers
Amantidine (Symmetrel) indications
Used early in course of PD, usually effective for only 6-12 months
Amantidine (Symmetrel) contraindication
Known drug allergy
Amantidine (Symmetrel) adverse effects
Mild: dizziness, insomnia, nausea
List two examples of COMT inhibitors
Tolcapone (Tasmar) and entacapone (Comtan)
COMT inhibitors MOA
Block COMT, the enzyme that catalyzes the breakdown of the body’s catecholamines
__________ prolong the duration of action of levodopa (particularly when given w/ carbidopa) and reduce the wearing-off effect
COMT inhibitors
COMT inhibitors contraindications
Known drug allergy; liver failure (w/ tolcapone — which is why it is not a first-line tx)
COMT inhibitors adverse effects
GI upset, urine discoloration, dyskinesia
Subclasses of Nondopamine dopamine receptor agonists (NDDRAs) for PD
Ergot and Nonergot derivatives
Example of an ergot derivative NDDRA
Bromocriptine (Parlodel)
Examples of Nonergot derivative NDDRAs
Pramipexole (Mirapex), ropinirole (Requip), rotigotine (Neupro)
All _________ work by direct stimulation of presynaptic and/or postsynaptic dopamine receptors in the brain
NDDRAs
PD drug that works by activating presynaptic dopamine receptors to stimulate the production of more dopamine
Bromocriptine (Parlodel)
Bromocriptine (Parlodel) contraindications
Drug allergy, used in conjunction with adrenergic drugs (Cardiovascular risk)
Bromocriptine (Parlodel) adverse effects
Ataxia, depression, GI upset, visual changes
Benefits of Nonergot NDDRAs
More specific Antiparkinson effects w/ fever adverse effects, used in both early and late stages of PD, may delay need for levodopa
Nonergot NDDRAs contraindications
Drug allergy, not to be used concurrently w/ adrenergic drugs
Adverse effects of Nonergot NDDRAs
Edema, fatigue, syncope
Anticholinergics MOA
Block the effects of Ach
Anticholinergics indications
Used to treat muscle tremors and muscle rigidity associated with PD
Anticholinergic SLUDGE behaviors
Ach causes increased salivation, lacrimation, urination, diarrhea, GI motility, and emesis
How to take anticholinergics
At bedtime; do not take with other PD drugs
Anticholinergic drugs used for PD and EPS symptoms from antipsychotic drugs
Benztropine (Cogentin)
Benztropine (Cogentin) contraindications
Known drug allergy; hot weather or activities that increase temp (risk for hyperthermia)
Anticholinergic adverse effects
Tachycardia, confusion, disorientation, toxic psychosis, urinary retention, dry throat, constipation, N/V
Indirect acting cholinergic drugs for myasthenia gravis
Acetylcholinesterase inhibitors such as Pyridostigmine (Mestinon)
Antidote for acetylcholinesterase inhibitors
Atropine
Pyridostigmine (Mestonin) MOA
Increases acetylcholine by inhibiting acetylcholinesterase
Pyridostigmine (Mestonin) contraindications
Drug allergy, asthma, gangrene, CV disease, GI obstruction
Pyridostigmine (Mestinon) adverse effects
GI upset, excessive salivation
Pyridostigmine (Mestonin) indications
Used to improve muscle strength in MG crisis
Multiple sclerosis mainstays of treatment include
Antispasmodics and immunosuppressants such as corticosteroids
Synthetic protein similar in structure to myelin that helps with remyelination in patients with MS
Glatiramer acetate (Copaxone)
First-line oral immunomodulator for treatment of MS
Fingolimod (Gilenya)
Fingolimod (Gilenya) side effects
Bradycardia (especially within first 6 hr after taking it), facial flushing, GI upset
Fingolimod (Gilenya) patient education
Take pulse everyday (d/t bradycardia)
Aside from Fingolimod (Gilenya), what are other immunomodulators for MS?
Interferon Beta
Patients with MS can use Medical cannabis to reduce
Muscle spasms