everything Flashcards
What three drugs are FDA-approved for tx of fibromyalgia?
Pregabalin
Duloxetine
Milnacipran
What is Pregabalin used for and what is the dose?
Fatigue
300-450 mg/day
What is Duloxetine used for and what is the dose?
Mood
60-120 mg/day
What is Milnacipran used for and what is the dose?
Pain, insomnia
100-200 mg/day
What is the mechanism of action for Duloxetine and Milnacipran?
Selective serotonin and norepinephrine reuptake inhibitor
What is the first line of treatment for spasticity associated with FM?
Baclofen
What is the mechanism of action for Baclofen?
GABA-B agonist
What is the first line of treatment for spasticity associated with MS or spinal cord injury/disease?
Tizanidine
Recommended dose of Tinazidine
2 mg daily, then increased every 3-4 days, 2 mg each time
T/F: Tinazidine can be used for children
False
Treatment for nocturnal muscle spasms
Flexeril
What drug is used to diagnose myasthenia gravis?
Erdrophonium
What drug is used to treat MG and Lambert-Eaton?
Pyridostigmine Bromide
Mechanism of action for cholinesterase inhibitors
Acetylcholinesterase cleaves ACh into Acetate and Choline, but Cholinesterase inhibitors, such as Carbamate, can bind Acetylcholinesterase in the place of Acetate and enhance the time that ACh is in the synapse
Anticholinesterase that does NOT enter the CNS
Neostigmine
Antidote for neuromuscular blockers, Myasthenia Gravis, GI and Urinary Tract Retention
Not used due to extreme side effects
Neostigmine
Why is Pyridostigmine used instead of Neostigmine?
Fewer side effects and longer duration of action
Antidote for carbamate poisoning
Atropine
Carbamate poisoning causes…
SLUDGE leading to bronchospasm and respiratory failure
Mechanism of action in carbamate poisoning
Peripheral effects on skeletal NICOTINE receptors —> depolarizing blockade
Why are individuals with NMJ diseases more sensitive to skeletal muscle relaxants?
Skeletal muscle relaxants decrease the amount of depolarization that occurs at the NMJ, therefore patients with NMJ diseases who already have low levels of depolarization will be more affected by these drugs
FAST ONSET (60-70 sec), but duration of action is 28 minutes MINIMAL CV SIDE EFFECTS, ALLERGIC REACTIONS
Rocuronium
SLOW ONSET and eliminated by HOFMANN DEGRADATION
NO HISTAMINE RELEASE and has CV STABILITY
Cis-Atracurium
What is the prototype NM blocking drug?
Curare (Tubocurarine)
What are the drawbacks of tubocurarine?
- Blocks ganglia (loss of control of BP),
- Affects muscarinic receptors (loss of parasympathetic control of heart rate → tachycardia)
- Releases histamine → hypotension, bronchoconstriction and anaphylaxis
- Duration of action is over 30 min (too long for short procedures such as intubation)
Succinylcholine mechanism of action
Depolarizing. Acts like ACh and activates postsynaptic receptor → receptor channel opens
How does succ stay in the post-synaptic cleft?
Succ not hydrolyzed by Synaptic AChE (only by plasma AChE)
What is the only remaining NM blocking drug that works by depolarizing APs?
Succinylcholine
Why is succ-induced depolarization in the peri-junctional muscle short-lived?
Na+ channels inactivated → propagation of depolarization is blocked
T/F: Succinylcholine is a depolarization agonist
True
What are two main short acting aminosteroids?
Vecuronium, Rocuronium
Which drug is active against Vecuronium and Rocuronium, but not against Succinylcholine?
Sugammadex
Gamma-cyclodextrin ring with lipophilic cavity
Sugammadex
Tracts/nerves affected in Weber’s syndrome
CN III
Corticospinal
Corticobulbar
Possible etiologies for Weber’s
Medial midbrain lesion
PCA occlusion
Ipsilateral down and out/dilated eye Contralateral hemiparesis UMN motor weakness Exaggerated gag reflex Spastic tongue Spastic dysarthria
Weber’s syndrome
Patient cannot look up. She most likely suffers from….
Parinaud’s syndrome
Vertical gaze palsy
Pupils accommodate, but do not constrict to light
Parinaud’s
Parinaud’s + non-communicating hydrocephalus indicates which additional structure has been affected?
Cerebral aqueduct
Structures affected in Parinaud’s syndrome
Superior colliculi
Pretectal area
Lateral gaze palsy. Which nerve is affected?
CN VI
Which three structures conduct lateral gaze and what level of the brainstem are they located in?
CN VI
PPRF
MLF
Pons.
Classic cause of lateral pontine syndromes
AICA stroke
Classic cause of medial medullary syndrome
Anterior spinal artery stroke
Classic cause of Wallenberg’s syndrome
PICA stroke
Patient has complete motor weakness. We know they don’t have…..
ACA or MCA stroke
Hemiplegia + down and out eye = ______
Weber’s syndrome
Location of Weber’s syndrome in brainstem
Medial midbrain lesion
Location of Wallenberg’s syndrome in brainstem
Lateral medullary lesion
What mediates the corneal reflex?
V: detects
VII: blinks
MLF lesion presentation
Nystagmus in contralateral eye
What is the only cranial nerve that exits dorsally?
CN IV
Cavernous sinus occlusion would cause…
Abducens lesion (Lateral gaze palsy)
Which cranial nerves synapse in the nucleus ambiguus?
IX, X, XI
Jugular foramen occlusion would cause…
Inability to turn head to affected side
Gag reflex is afferent or efferent?
Afferent
What tract provides sensory innervation for the pharynx and larynx?
Spinal trigeminal
FDA approved drug for fibromyalgia
Minalsaprin
Which level of the brainstem is the red nucleus located in?
Midbrain
What extraocular structures does CNIII innervate?
Super, medial, inferior rectus
Inferior oblique
What structure does CN IV innervate?
Superior oblique
Which structures yield contralateral deficits?
Spinothalamic
Medial lemniscus
Trigeminal lemniscus
Corticospinal
Which structures yield only ipsilateral deficits?
Cranial nerves
Descending tract of V
Posterior columns in the lower medulla
A lesion involving which structures would yield ipsilateral cranial nerve deficits and contralateral loss of pain and temperature sensations from the body?
CNs V, VII, IX, X, and XI exit the brainstem in close proximity with the spinothalamic tract. As a result, a lesion in one of these regions may involve one of these nerves as well as the spinal lemniscus.
A lesion involving which structures would yield cranial nerve deficits with alternating hemiplegia?
CNs III, V, VI, XII + Corticospinal tract
Which cranial nerves exit the brainstem adjacent to the corticospinal tract?
III, V, VI, XII
Unilateral lesion of the CST would cause which symptoms?
Contralateral spastic hemiplegia
Unilateral lesions of the CBT above the level of the decussation results in what symptoms?
Contralateral paralysis of the mimetic muscles of the lower face –> supranuclear facial palsy
Cranial palsies due to denervation of abducens nuscleus, hypoglossal nucleus, and nucleus ambiguus
Unilateral lesions of the CBT below the level of decussation would cause what symptoms?
Ipsilateral cranial nerve palsies