Week 1 antiepileptic 4 of 4 (6/3) Flashcards
slide 72-94
these three side effects are more commonly associated with bromocriptine than those treated with levodopa.
hypotension
auditory and visual hallucinations
dyskinesia
what med classification can occasionally cause pleuropulmonary fibrosis sometimes with pleural effusions?
synthetic dopamine agonists.
what med classification can cause erythromelalgia (red, edematous, tender extremities)
uncommon complication
synthetic dopamine agonist
synthetic dopamine agonists can cause an asymptomatic increases in what laboratory finding
serum transaminase (ALT)
alkaline phosphate (ALP)
liver enzymes
what side effects are occasionally associated with bromocriptine
vertigo and nausea
with respect to CNS side effects is there an advantage of non ergot alkaloids over ergot derivatives?
no
with respect to nausea and orthostatic hypotension, is it important that non ergot alkaloids cause less nausea and orthostatic hypotension than ergot derivatives
this is clinically INsignificant.
what are the effects of anticholinergic drugs such as trihexyphenidyl and benztropine on parkinson’s disease
blunt the effects of ACH- correcting the balance between dopamine and ACH
what do anticholinergic drugs specifically help control in patients with parkinson’s disease
tremors and decrease the excess salivation.
do anticholinergic drugs help parkinsons patients with their skeletal muscle rigidity and bradykinesia
no
what are the side effects of treating parkinson patients with synthetic anticholinergic drugs?
anticholinergic drugs to treat patients with parkinson’s disease has diminished.
memory disturbances hallucinations confusion sedation mydriasis cycloplegia adynamic ileus urinary retention
name the antiviral drug used for prophylaxis against infection with influenza A
amantadine
discovered by chance, this drug also produces symptomatic improvement in patients with parkinson’s disease
amantadine
amantadine is speculated to aid parkinson’s patients by these three mechanisms
facilitating the release of dopamine from dopaminergic terminals
delay uptake of dopamine back into nerve endings
antagonist effects at NMDA receptors.
amantadine is different from anticholinergics drugs for in its ability to improve what two symptoms
muscle rigidity
bradykinesia
side effects of amantadine are similar to anticholinergics but in addition can induce
ankle edema
livedo reticular of the legs with or without cardiac failure
Livedo reticularis is a rare skin condition caused by stagnation of blood within dilated capillaries causing a lacy, nonraised pink/purple net-like blotchy skin discoloration -google_
non pharmacologic treatments of parkinson’s disease include
deep brain stimulation
deep brain stimulation mechanism of action?
what specific benefit to the patient does it provide
unknown MOA
benefits controls symptoms resistant to medications, allows reduced reliance of drugs.
what type of drugs are selegiline and rasagiline
monoamine oxidase type B enzyme inhibitors (MAO-B)
MAO-B antiparkinson effect when used alone?
MAO-B antiparkinson effect when combined with carbidopa-levodopa
alone- weak
adjunt- moderate effect
name the significant side effect of selegiline
insomnia
other side effects of selegiline
confusion, hallucinations, mental depression paranoid ideation
avoidance of tyramine is ideally recommended if patient is on what class of medication
MAO-B
what two ways do analeptics increase excitability
blocking inhibition or by enhancing excitation
this class of medication was used in CNS depressions after a person deliberately overdosed on drugs- No longer used for this purpose
CNS stimulants
CNS stimulants margin of safety is___
low
This centrally acting analeptic also acts peripherally on chemoreceptors augmenting breathing efforts
doxapram
doxapram 1mg/kg IV dose is similar to that produced by a pa02 of _____ acting on the carotid bodies
38
are doxapram positive effects seen because of increasing in breathing frequency or increase in tidal volume?
increase in tidal volume is response for the induce increase in minute ventilation
doxapram increase minute ventilation- what happens to o2 consumption
o2 consumption increases
doxapram margin of safety?
large margin of safety
how many fold difference in the dose that stimulates ventilation and the dose that produces seizures for doxapram
20-40 fold difference
how long dose a single dose of doxapram last?
due to this what must we do?
single dose 5-10min
continuous infusion may be required
a continuous infusion of doxapram often results in what clinical manifestations?
sub convulsive CNS stimulatiion HPTN tachy cardiac dysrhythmias vomiting increased body temp
how extensive is doxapram metabolized?
what percent is excreted unchanged in the urine
extensively metabolized
<5%
doxapram iv infusion dose
2-3mg/min
this drug can be used to maintain ventilation during administration of supplemental 02 to patients with COPD who would otherwise rely on hypoxic drive to maintain
doxapram
post operatively doxapram has been used to prevent { this } produced by opioids without altering analgesia
ventilatory depression
other than helping patients breath- why else would we want to give doxapram to our post op patients
shown to be useful in stopping post op shivering
what can we administer to neonates in the ICU in lieu of placing an advanced airway
doxapram used for apneic babies to delay or prevent intubation and ventilation
what 4 conditions can we give dantrolene for
Thyroid storm
NMS-neuroleptic malignant syndrome
spastic disorders- associated with hepatic dysfunction
MH
compare dantrolene to ryanodex
sterile water to reconstitute
dantrolene-60ml
ryanodex- 5ml
compare dantrolene to ryanodex
shelf life
dantrolene 3 years
ryanodex 2 years
compare dantrolene to ryanodex
mannitol
dantrolene 3000mg
ryanodex 125mg
why do we not used ryanodex?
its more expensive (2,581) vial
revonto vial contains how many mg
ryanodex vial contains how many mg
revonto- 20mg
ryanodex -250mg
ryanodex has enough dantrolene in a single vial for a loading dose in what kg patient
100kg
most serious complication of dantrolene use?
generalized muscle weakness that may result in respiratory insufficiency or aspiration PNA
why do we use a CVL with dantrolene
can cause phlebitis in small peripheral veins
dantrolene dose
2.5mg/kg- 10mg/kg q5min until episode has stopped
follow up with 1mg/kg q6hrs for 24-48 hrs
dantrolene vs ryanodex time to reconstitute
86sec vs 20sec
mechanism of action for dantrolene
DIRECTLY INTERFERES WITH MUSCLE CONTRACTION BY BINDING THE Ryr1 RECEPTOR CHANNEL AND INHIBITING CALCIUM ION RELEASE FROM THE SARCOPLASMIC RETICULUM
per flood- half life of dantrolene
9 hrs
dantrolene exerts antispasmodic effect by decrease what release from SR
calcium
PO absorption of dantrolene?
slow and incomplete
starting oral dose of dantrolene
25mg BID
max oral dose of dantrolene
200mg/day
what do we have to check prior to starting dantrolene?
lab investigation for liver dysfunction should be explore prior to use d/t potential hepatotoxicity
primary indication for centrally acting muscle relaxants
spasticity with accompany pathologic conditions such as stroke, cerebral palsy, multi sclerosis, amyotrophic lateral sclerosis and CNS injuries.
centrally acting muscle relaxants act where
on CNS or on skeletal muscles to relieve spasticity
this medication is a chlorophenol derivative of GABA
baclofen
does baclofen have any effect on the NMJ
no
where does baclofen act as an agonist
at GABA (B) receptors in the dorsal horn of the spinal cord
what is baclofen often administered for treatment of
spastic hypertonia of cerebral and spinal cord origin
MOA- baclofen
activating G protein linked presynaptic gaba b receptors that hyper polarize muscles spindle afferent neurons. there by decreasing the number and amplitude of excitatory postsynaptic potentials along the dendrites of motor neurons
baclofen is particularly effective in treatment of
Flexor spams
Skeletal muscle rigidity associated with spinal cord injury or MS
which administration route may be an effective treatment of spinal spasticity that has not responded to oral adminstration
intrathecal
how is baclofen absorbed in the gi tract
rapidly and almost completely
elimination half time for baclofen
3-6hrs
what percent of baclofen is excreted by the kidneys
80%
dose may need to be adjusted with renal dysfunction
side effects of baclofen
sedation
skeletal muscle weakness
confusion
if you suddenly d/c chronic use of baclofen what may occur
withdrawal
therapeutic plasma concentrations of baclofen
80-400mg/ml
accidental intrathecal overdose of baclofen
hemodynamic instability and delayed awakening following general anesthesia
overdose of baclofen
seizure concerns
Threshold for initiation of seizures may be lowered in pts with epilepsy
sudden d/c of baclofen vocal cord concerns
Vocal cord spasm following abrupt d/c of intrathecal infusion
what may occur with an overdose of baclofen
Coma, depression of ventilation and seizures with overdose
Sudden d/c of chronic baclofen use may result in severe withdrawal reactions:
Tachy
Auditory and visual hallucinations
A known case of cardiac arrest has been reported
this CNS stimulant is a methylxanthine derived phosphodiesterase inhibitor that is present in a variety of drinks
CAFFEINE!!
(3) pharmacologic uses of caffeine include
administration to neonates experiencing apnea of prematurity
treatment for postural puncture headache
common cold remedies to offset the sedating effects of certain antihistamines
this medication is used for patients with excessive day time sleepiness associated with narcolepsy, OSA, shift work sleep disorder
modafinil
this drugs acts on the carotid body chemoreceptors to increase minute ventilation
almitrine
this drug is used to prevent one lung ventilation hypoxia
almitrine
caffeine, theophylline and theobromine are called
methylxanthines
methylxanthines can do what 4 things
stimulate CNS
produce diruesis
increase myocardial contractility
relax smooth muscle
this drug treats ADHD
methylphenidate
side effects seen with methylphenidate
HTN tachycardia priapism seizures serious cardiovascular events stroke MI
carbamazepine and rifampin interaction with theophylline produce
enhancement of theophylline
cimetidine, erythromycin interact with theophylline produce
inhibition of theophylline
how must benzo’s be administered in the presence of theophylline
you must increase the dose of benzo
what may occur in patients being treated with oral baclofen
mild hypotension in awake patients
patients treated with oral baclofen given general anesthesia may experience
bradycardia and hypotension and delayed awakening.
