dopaminergics and muscle relaxants

Question 1

carbidopa-levodopa (sinemet)

pharmacodynamics

Answer 1

parkinsons disease
levodopa circulates in the plasma to the blood-brain barrier where it crosses to be converted by enzymes to dopamine.
And carbidopa inhibits the peripheral plasma breakdown of levodopa, thereby increasing the availability of levodopa at the blood-brain barrier.

Question 2

carbidopa-levodopa (sinemet)

caution and contraindications

Answer 2

avoid in narrow angle glaucoma,
major psych dx,
malignant melanoma
cardiovascular disease,
elderly patients

Question 3

carbidopa-levodopa (sinemet) patient education

Answer 3

take without food

Question 4

carbidopa-levodopa (sinemet) ADRs

Answer 4

orthostatic hypotension, somnolence, dizziness, headache, insomnia, abnormal dreams can occur, dyskinesia,

Rare: neuroleptic malignant syndrome and peripheral neuropathy.

Question 5

dopaminergic

Answer 5

carbidopa-levodopa (sinemet)

Question 6

muscle relaxant

Answer 6

cyclobenxaprine (flexeril),
baclofen (lioresal),
metaxalone (skelaxin)
tizanidine (zanaflex)
methocarbamol (robaxin)

Question 7

baclofen indications and pharmacodynamics

Answer 7

severe muscle spasms, MS, ALS, spactisity

which inhibits the transmission of both monosynaptic and polysynaptic reflexes at the spinal cord level, possibly by hyperpolarization of primary afferent fiber terminals, which results in the relief of muscle spasticity

Question 8

baclofen caution and contraindications

Answer 8

renal impairment,
elderly (beers list(),
seizure disorder,
avoid in preganncy,
caution in lactation

Question 9

baclofen ADRs

Answer 9

drowsiness, confusion, headache, nausea, vomiting, hypotension, and seizures.

Question 10

cyclobenxaprine (flexeril)

Answer 10

acts on monosynaptic and polysynaptic spinal reflexes, inhibiting the monosynaptic reflex affects the messages that are producing and maintaining the skeletal muscle spasms.

Question 11

cyclobenxaprine (flexeril) ADRs

Answer 11

They can cause dry mouth, drowsiness, constipation, hallucinations, blurred vision. And there is a risk for serotonin syndrome.

Question 12

cyclobenxaprine (flexeril) caution and contraindications

Answer 12

hyperthyroidism,
heart failure,
arrhythmias, heart blocker conductions or disturbances,
acute recovery phase of having an MI.
patients with urinary retention,
angle-closure glaucoma, or increased ocular pressure; caution in hepatic impairment.

approved in peds > 12 y/o.
limited data in preganacy and lactation

med not to be used longer than 3 weeks

Question 13

Tizanidine pharmacodynamics

Answer 13

which is a centrally acting alpha-2 adrenergic agonist, which we’re actually going to be talking about soon in this lecture, that reduces muscle spasticity by presynaptic inhibition of motor neurons

Question 14

tizanidine ADRs

Answer 14

dry mouth, weakness, fatigue, constipation, hypotension, bradycardia.

rare: anaphylaxis and angioedema

Question 15

tizanidine caution and contrainidcations

Answer 15

hepatic impairement,
caution in renal impairement,
caution in elderly,
avoid in pregancy and lactation,
peds limited data.

Question 16

tizanidine patient education

Answer 16

do not take with alcohol

can cause rebound tachycardia if stopped.

Question 17

A 45-year-old patient is suffering from back pain due to severe muscle spasms. A centrally-acting muscle relaxant, tizanidine (Zanaflex), is prescribed. By which mechanism of action does tizanidine act?

Answer 17

Tizanidine (Zanaflex) binds to central alpha2 adrenergic receptors, which increases the presynaptic motor neuron inhibition and reducing spasticity.

Question 18

treatment of choice for parkinsons

Answer 18

carbidopa-levadopa,
levodopa, 
amantadine (symmetrel),
bromocriptine (parlodel).
ropinirole (requip),
pramipexole (mirapex),

Question 19

ADRs of dopaminergics

Answer 19

n/v, hallucinations, dizziness

Question 20

monitoring of dopiminergics

Answer 20

hepatic panels d/t risk for hepatocellular injury

Question 21

education of dopiminergics

Answer 21

avoid abrupt d/c, avoid antacids

Question 22

drug interactions with dopiminergics

Answer 22

antacids

Question 23

who must you avoid giving muscle relaxant to?

Answer 23

pregnant women. it can cause uterus to relax and cause miscarriage

Question 24

muscle relaxants drug interactions

Answer 24

CNS depressants and sedation