Pharm 31 Objectives Flashcards Preview

Neuro > Pharm 31 Objectives > Flashcards

Flashcards in Pharm 31 Objectives Deck (69)
Loading flashcards...
1
Q

What is the pharmacodynamics of Benzodiazepines?

A

They bind to GABA receptors and increase the frequency of GABA linked Cl- channel opening.

2
Q

What is the pharmacodynamics of Barbiturates?

A

At low to moderate doses they prolong the time/duration of opening the Cl- channel causing them to have a more potent effect than benzos as well as inducing their own metabolism.

3
Q

What is the pharmacodynamics of Gabapentin?

A

Blocks voltage gated n-type calcium channel by binding to the alpha2-delta and prevents the exocytosis of neurotransmitters by presynaptic cleft, and reduced glutamate.

4
Q

What is the pharmacodynamics of Pregabalin?

A

Blocks voltage gated n-type calcium channel by binding to the alpha2-delta just like Gabapentin but has a more potent effect and its better absorbed.

5
Q

What is the Pharmacokinetics of Phenytoin?

A

Saturable (non-linear) metabolism and a broad spectrum hepatic enzyme inducer. (makes other drugs less effective)

6
Q

What is the Pharmacokinetics of Fosphenytoin?

A

It has an added phosphate group which increases solubility. Compared to phenytoin it is 3x faster administered IV but not faster acting.

7
Q

What is the Pharmacokinetics of Diazepam?

A

Has some interpatient variability d/t having an active metabolite resulting in a longer duration of action

8
Q

What is the Pharmacokinetics of Lorazepam?

A

Less interpatient variability, medium duration of action, no active metabolite, bypass phase 1 of metabolism.
- 1st line in ER for seizures

9
Q

What is the Pharmacokinetics of Clonazepam?

A

Less interpatient variability, medium duration of action, no active metabolite, bypass phase 1 of metabolism.

10
Q

Describe the mechanism of prolonging/enhancing an inactive state of Na+ channel?

A

Prevents repeat firing of a neuron.

11
Q

Describe the mechanism of modulation/blockage of voltage gated Ca2+ channel?

A

Prevents the exocytosis of neurotransmitters by the presynaptic neuron.

12
Q

Describe the mechanism of Pharmacologic enhancement of GABA neurotransmission?

A

Causes an activation of Cl- channel and hyperpolarizes the neuron which decreases the chance of an action potential.

13
Q

Describe the mechanism of inhibited glutamate neurotransmission?

A

Glutamate is an excitatory neurotransmitter that increases the neuron firing and action potential so by inhibiting it, it decreased the chances of a neuron firing an action potential.

14
Q

What is enzyme-inducing?

A

Increases the rate of hepatic metabolism causes other dugs to be less effective.

  • Can lad to loss of hormonal contraception’s
  • Induce congenital abnormalities
  • Bone loss
15
Q

What is enzyme-inhibiting?

A

Compete or displace protein bringing sites which results in increases free/active drug levels, increasing risk for toxicity.

16
Q

What anti-seizure drug has the greatest potential for teratogenicity

A

Valproate

17
Q

What anti-seizure drugs are FDA category D for pregnant pts?

A
Phenobarbital
Carbamazepine
Phenytoin
Fosphenytoin
Benzodiazepines
18
Q

What is 1st and 2nd line tx for generalized tonic-clonic status epilepticus?

A

1st: Lorazepam
2nd: Phenytoin

19
Q

What is 1st and 2nd line tx for absence epilepsy?

A

1st: Ethosuximide
2nd: Valproate

20
Q

What 2 black box warnings are on antiseizure drugs?

A
  1. Depression/suicidality

2. Abrupt discontinuation

21
Q

Why is Depression/suicidality a black box warning?

A

Death rates from suicide are 2.5-6x higher in pts with epilepsy and some drugs may cause worsening depression or suicidal ideation.

22
Q

Why is abrupt discontinuation a black box warning?

A

Risk of withdrawal seizers especially true with benzos and barbiturates.

23
Q

How would you adjust the dose of phenytoin during a toxicity episode?

A

Titrate to a lower dose and monitor serum levels

24
Q

How would you adjust the dose of phenytoin during an increased seizure activity?

A

You cannot double phenytoin as it is an increased risk for tox d/t a very narrow therapeutic range

  • slowly titrate to higher dose,
  • Normal dose is 300-400 for 18-64 years old, <300 for elderly, and >400 for rapid metabolizers.
25
Q

What antiseizure drugs are FDA approved for postherpetic neuralgia?

A

Gabapentin and Pregabalin

26
Q

What antiseizure drug is FDA approved for diabetic peripheral neuropathy?

A

Pregabalin

27
Q

What antiseizure drug is FDA approved for fibromyalgia?

A

Pregabalin

28
Q

What antiseizure drug is FDA approved for Trigeminal Neuralgia?

A

Carbamazepine

29
Q

Identify an opioid-like medication (from Pharm-19) with serotonin and norepinephrine reuptake inhibition which can represent a better option than NSAIDs and full opioid agonists for neuropathic pain, so long as you avoid excessive serotonin neurotransmission and abuse/misuse?

A

Tramadol

30
Q

What FDA approved antiseizure drugs used to tx bipolar disorder?

A

Valproic Acid
Carbamazepine
Lamotrigine

31
Q

When is Lamotrigine and Valproic acid used together?

A

It is used used together for seizures or bipolar disorder

32
Q

What caution is given when taking Lamotrigine and Valproic acid together?

A

Lamotrigine is UGT substrate and Valproate is a UGT inhibitor which means when taking them together you start with half the normal dose of Lamotrigine.

(Just FYI take one tab every OTHER day instead of every day, if this is not adjusted than there is a much higher risk for a severe lamotrigine rash)

33
Q

How would you respond to a pt who comes in complaining of a rash after taking Lamotrigine?

A

D/c lamotrigine immediately!

34
Q

How would you respond to a pt who comes in complaining of a rash after taking other AEDs (except for Lamotrigine)?

A

The clinician would need to slowly d/c the medication by titrating the dose to prevent withdrawal seizers from occurring.

35
Q

How is the response different from rashes caused by AEDs vs rashes caused by histamine release?

A

Histamine release is a normal response not necessarily a hypersensitivity reaction and typically does not result in immediate medical attention.
A pt would be treated with an antihistamine to prevent the rash from reoccurring while continuing current medication regimen.

36
Q

Compare Lamotrigine and Valproic acid used to treat bipolar disease?

A
  • Lamotrigine is used as maintenance only d/t risks of severe rash
  • Valproic acid can be used for acute mania /t no risk for rash
37
Q

What drug treats partial or primary generalizes tonic-clonic seizures AND is a migraine prophylaxis?

A

Topiramate

38
Q

Is Topiramate a CYP3A inducer or inhibitor?

A

Inducer

39
Q

What unique ASEs are caused by Topiramate?

A

Difficulty with memory
Paresthesias
Psychomotor slowing

40
Q

What drug treats many general seizures and AND is a migraine prophylaxis?

A

Valproate

41
Q

Is Valproate a hepatic enzyme inducer or inhibitor?

A

Inhibitor especially UGT

42
Q

What is one MC ASE of Valproate?

A

Weight gain

43
Q

What is recommend to pts with migraine w/ auras who are on contraceptives?

A

D/t taking contraceptives with estrogen and progesterone advised taking one with progesterone only.

44
Q

What medication would you prescribe to a pt with depression, migraines, and neuropathic pain?

A

Amitriptyline

45
Q

What medication is used to treat both depression and migraines but has less clinical evidence compared to others?

A

Venlafaxine (SNRI)

46
Q

What medications are used to both HTN and migraines?

A

Propranolol and Timolol (Beta Blockers)

47
Q

What are the black box warnings for Cabamenzamine?

A
  • HLA-B* 2502 inherited allelic variant

- Aplastic anemia and agranulocytosis.

48
Q

D/t the black box warning for Cabamenzamine what is required?

A
  • Genetic testing for all pts especially those of Asian ethnicity.
  • monitor CBC
49
Q

What vascular and dermal rxn is caused by phenytoin IV?

A

Purple glove syndrome

50
Q

What neuro rxn is caused by phenytoin IV?

A

Ataxia, confusion, dizziness

51
Q

What cardiovascular rxn is caused by phenytoin IV?

A

Dysrhythmia, HypoTN, bradycardia

52
Q

Why should carbonic anhydrase inhibitors (ie Acetazolamide) and the keto diet not be utilized simultaneously by the same pt?

A

Risk for acidosis

53
Q

What is the primary mechanism of action of Phenytoin and Fosphenytoin?

A

Na+ channel blocker

54
Q

What is the primary mechanism of action of Gabapentin and Pregabalin?

A

Ca+ channel blocker

55
Q

What is the primary mechanism of action of Carbamazepine?

A

Na+ channel blocker

56
Q

What is the primary mechanism of action of Lamotrigine?

A

Na+ channel blocker

57
Q

What is the primary mechanism of action of Ethozuximide?

A

Ca+ channel blocker

58
Q

What is the primary mechanism of action of Barbiturates and Phenobarbital?

A

Positive allosteric effector (increases activity) of GABA-A receptor

59
Q

What is the primary mechanism of action of Benzodiazepines?

A

Positive allosteric effector (increases activity) of GABA-A receptor

60
Q

What is the specific titration schedule for Lamotrigine?

A

Weekly dose titration for at least 4 weeks

61
Q

What is the ASEs of Phenytoin?

A
P-450 interactions
Hirsutism
Enlarged gums
Nystagmus
Yellow - browning of skin
Teratogenicity
Osteomalacia
Interference with B12 metabolism (anemia)
Neuropathies: vertigo, ataxia, HA.
62
Q

What are the 4 safest antiseizure drugs for pregnancy?

A

Lamotrigine
Levetiracetam
Gabapentin
Zonisamide

63
Q

What is the Pharmacokinetics of Valproic Acid?

A

Free acid form, readily absorbed by the GI tract and is a hepatic enzyme inhibitor especially UGT

64
Q

What is the Pharmacokinetics of Sodium Valproate DR?

A

Well tolerated by patients because it prevents GI upset from the enteric coating which causes the delay, has less bioavailability compared to ER

65
Q

What is the Pharmacokinetics of Sodium Valproate ER?

A

The medication is released over a longer period of time after being administered and therefore more bioavailability than DR, but no enteric coating which can cause some GI upset.

66
Q

Pharmacodynamics of Primidone?

A

Na+ blocker

- The active metabolite is phenobarbital

67
Q

Oxcarbamezapine ASE?

A

Increase in hyponatremia

- safer than carbamazepine

68
Q

Zonisamide ASE?

A

Metabolic acidosis

69
Q

What causes “Keppra Rage”?

A

Levetiracetam