Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Step 1 > Pharmacology8-2 > Flashcards

Pharmacology8-2 Flashcards

1
Q

What is the mechanism of action for a benzodiazepine?

A

Benzo’s bind to the GABA-A receptor-chloride channels in the CNS and increase the frequency at which they open.

This results in: (1) anxiolytic (2) anticonvulsant (3) muscle relaxant & (4) sedative-hypnotic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Glanzmann thrombasthenia is a rare bleeding disorder that typically presents in childhood with mucocutaneous bleeding. Peripheral blood smear would show no platelet clumping. What type of anti-coagulation drugs most closely mimic Glanzmann thrombasthenia?

A

Individuals with GT lack a functional glycoprotein IIb/IIIa platelet surface receptors. Anti-coagulant drugs that block the GPIIb/IIIa receptor (i.e Abciximab) would most closely resemble this illness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Treatment:

Mycobacterial infection in a patient on HAART

A

Rifabutin

Typically, rifampin is used for mycobacterial infections; however, in patients concurrently taking a protease inhibitor, rifampin is contraindicated due to it’s ability to induce the activity of P-450. Rifampin would result in decreased serum levels of protease inhibitor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the shared side effects of protease inhibitors?

A

(-avir)

  1. Lipodystrophy
  2. Hyperglycemia
  3. Inhibition of P-450

Each protease inhibitor has additional side effects. For example, idinavir also causes nephrotoxicity and nephrolithiasis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which organisms are not covered by cephalosporins?

A

The LAME ones. (1) Listeria (2) Atypicals (chlamydia & Mycoplasma) & (3) Enterococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Mechanism of Action:

Penicillins

A
  1. covalently bind the active site of transpeptidase
  2. prevent crosslinking of peptidoglycan cell wall
  3. weak cell wall integrity causes osmotic lysis of the bacterium

Penicillins are structural analogs of D-Ala-D-Ala.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Diagnosis:

Your patient has a history of schizophrenia, treated with risperidone, and presents with (1) breast tenderness & (2) no menstrual periods for 3 months

A

Drug induced amenorrhea

Risperidone is an atypical antipsychotic. Many antipsychotics cause hyperprolactinemia due to their anti-dopaminergic actions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pathogenesis:

Risperidone induced amenorrhea

A
  1. Risperidone is an antipsychotic with anti-dopaminergic actions.
  2. Decreased dopamine releases the inhibitory break on prolactin production.
  3. Excess prolactin will shut down the HPA axis, preventing the production of GnRH, LH & FSH.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why might you consider prescribing a beta blocker to a patient on a anti-psychotic?

A

Anti-psychotic medications have some side effects: (1) Extrapyramidal side effects (2) Tardive dyskinesia & (2) Neuroleptic malignant syndrome. The beta-blocker would be helpful for a patient experiencing akathisia, a extrapyramidal side effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What the extrapyramidal side effects associated with anti-psychotic usage?

A

(1) Extrapyramidal side effects: acute dystonic reaction, akathisia & drug-induced parkinsonism
(2) Tardive dyskinesia
(3) Neuroleptic malignant syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Mechanism of Action:

Carbamazepine

A

blocks voltage gated Na channels in cortical neurons

Side effects: (1) Bone marrow suppression (2) hepatoxicity & (3) SIADH
Carbamazepine may be used to treat: (1) simple partial (2) complex partial & (3) tonic-clonic seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Treatment:

Status epilepticus

A
  1. IV lorazepam (simultaneously load phenytoin)
  2. Phenobarbital if refractory
  3. Intubation and general anesthesia if still refractory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Function:

Phenytoin

A

Phenytoin inhibits neuronal firing by reducing the ability of the sodium channels to recover from inactivation. Thus, at high frequency firing rates, the neuron is refractory to reactivation an seizure activity is reduced.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why are benzodiazepines first line therapy for status epilepticus over phenytoin?

A

Benzodiazepines have a rapid onset of action. Phenytoin takes approximately 15 minutes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name that antifungal!

Alters the fungal cell membrane composition by inhibiting the demethylation of lanosterol into ergosterol

A

(-azoles) Ketoconazole, fluconazole, itraconazole, voriconazole

This drugs also increase the serum concentration of drugs metabolized by liver P-450 enzymes like: warfarin, cyclosporine, tacrolimus, phenytoi, isoniazid, rifampin, oral hypoglycemics and others.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name that antifungal!

Causes pore formation and ultimately lysis by binding ergosterol in the fungal cell membrane

A

Polyene antifungals (i.e. Amphotericin B & nystatin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name that antifungal!

Decreases the synthesis of ergosterol by inhibiting the fungal enzyme squalene-2, 3, epoxidase

A

Terbinafine

Terbinafine is used to treat dermatophytoses as it accumulates in the skin and nails.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name that antifungal!

Inhibits fungal mitosis by binding polymerized microtubules and disrupting the fungal mitotic spindle

A

Griseofulvin

Griseofulvin is only effective for dermatophytosis because it accumulates in the skin and appendages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do cholinomimetics affect the smooth muscle tone of the detrusor muscle in the bladder?

A

Cholinomimetics would cause contraction of the detrusor muscle and promote urination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which anticonvulsant is most commonly used for seizure prophylaxis?

A

Valproate (Valproic acid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What drug is indicated to treat (1) major depression (2) obsessive-compulsive disorder & (3) anxiety disorders?

A

Sertraline (SSRI)

Do not prescribe sertraline to a bipolar person. It may induce mania.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Mechanism of Action:

Valproate

A
  1. Blocks Na channels
  2. Enhances GABA synthesis and release
23
Q

How would a muscarinic agonist affect the GI sphincter?

A

Muscarinic AGONISTS will increase tone in the visceral smooth muscle (i.e. GI tract). This promotes motility and GI secretions.

An anticholinergic drug would relax the GI wall and increase the contraction of the sphincters to cause constipation. (sympathetic activity slows down the GI tract!)

24
Q

How would a muscarinic agonist affect the peripheral blood vessels?

A
  1. Endothelial cells have muscarinic receptors that when activated promote NO release (aka endothelium-derived relaxing factor/EDRF)
  2. NO activates guanylate cyclase
  3. intracellular cGMP is increased
  4. cGMP activates a Ca pump that causes Ca efflux from the cells
  5. Decrease in calcium concentration causes vascular wall smooth muscle relaxation
25
Q

Name that antifungal!

Prevents fungal cell wall formation by blocking synthesis of 1,3-beta-D-glucan

A

Caspofungin and other echinocandin antifungals

1,3-beta-D-glucan is the main component of Candida and Aspergillus cell walls.

26
Q

Name that antifungal!

Inhibits fungal DNA and RNA synthesis by replacing uracil with 5-fluorouracin in fungal mRNA.

A

Flucytosine (antimetabolite that is transformed into 5-fluorouracil in the fungal cell)

Flucytosine is often used with Amphotericin B to produce a synergistic response. This treatment is commonly used for cryptococcal meningitis.

27
Q

What are the most signifcant side effects of metformin treatment?

A
  1. Gastrointestinal upset
  2. Lactic acidosis
28
Q

In what subset of patients would metformin be contraindicated?

A

Patients with renal failure due to the increased risk of lactic acaid accumulation.

It is also contraindicated in patients with liver dysfunction, congestive heart failure, alcoholism and sepsis.

29
Q

What type of antidote would you give to a patient suffering from cyanide poisoning?

A

Oxidizing nitrite agents, like amyl nitrite.

Nitrities cause methemoglobinemia, which avidly binds cyanide. This consumption of cyanide by methemoglobin reduces cyanides ability to bind iron-containing enzymes like cytochrome a-a3, a complex critical for electron transport during oxidative phosphorylation.

30
Q

Diagnosis:

(1) decreased visual acuity
(2) central scotoma
(3) color blindness

A

optic neuritis due to ethambutol toxicity

31
Q

Mechanism of Action:

Ethambutol (antimycobacterial)

A
  1. inhibits carbohydrate polymerization (arabinose to arabinan to arabinogalactan; via arabinosyl transferase)
  2. prevents peptidoglycan cell wall synthesis
32
Q

What are the adverse effects of ethambutol therapy?

A
  1. hepatotoxicity (all antimycobacterial agents)
  2. ototoxicity
33
Q

What is the ONLY antituberculous drug that inhibits mycolic acid synthesis?

A

Isoniazid

34
Q

Reflex sympathetic activation (i.e. tachycardia and edema) is an adverse effect seen with which type of antihypertensive medications?

A

Direct arteriolar vasodilators (i.e. hydralazine and minoxidil) cause significant arterial vasodilation and reflex sympathetic activation.

35
Q

What additional drugs might you administer to a patient receiving hydralazine to prevent reflex sympathetic activation?

A

Sympatholytics or diuretics

Hydralazine is a direct arteriolar vasodilator that can lead to tachycardia and edema due to reflex sympathetic activation.

36
Q

Your patient is a burn victim with an oxidase-positive, non-lactose fermenting pathogen infection in his skin tissue. Which penicillin or cephalosporin drugs can you give to treat this patient?

A

(1) penicillin: ticarcillin, piperacillin
(2) cephalosporins: ceftazidime, cefepime

Note, you can also give aminoglycosides, fluoroquinolones (ciprofloxacin, levofloxacin) and carbapenems (imipenem, meropenem).

37
Q

Your patient is a 24-year-old female with low energy, decreaes appetite, 8lb weight loss in one month and insomnia. Her mother has a history of “mood swings”. This patient clearly seems depressed. Should you give her Venlafaxine?

A

You might, but be aware that venlafaxine is an SNRI antidepressant that has an increased risk of mood switches into mania in patients with undiagnosed bipolar disorder. This patients family history suggest that she may have bipolar. If the patient becomes manic you might want to consider a mood stabilizer and discontinue the use of anti-depressants.

38
Q

Which antidote would you administer to reverse organophosphate stimulation of BOTH muscarinic and nicotinic cholinergic receptors?

A

Pralidoxime, is the ONLY medication that can reverse the muscarinic and nicotinic effects of organophosphates. Atropine will only reverse the muscarinic effects. Thus if you administer atropine to a patient with organophosphate poisoning they will still be at risk for muscle paralysis due to increase spastic activity.

39
Q

Mechanism of action:

Niacin

A

Niacin inhibits VLDL production (i.e. Cholesterol –> VLDL). It is often prescribed to increase HDL.

40
Q

Which cholesterol lowering medication upregulates LDL receptors by inhibiting cholesterol synthesis?

A

Statins inhibit cholesterol synthesis in the hepatocytes (i.e. acetyl-CoA –> cholesterol). This upregulates LDL receptors on the liver cell membrane.

41
Q

Which medication is superior to aspirin in the treatment of peripheral arterial disease?

A

Cilostazol, a phosphodiesterase inhibitor. Cilostazol has two functions: (1) inhibition of platelet aggregation & (2) direct arterial vasodilation.

42
Q

What physiological effect is common to the following:
1. Atropine
2. TCA
3. H1 receptor antagonists
4. Neuroleptics
5. Antiparkinsonian drugs

A

antimuscarinic effects (eg flushed skin, mydriasis)

43
Q

antimetabolite drug that is similar to folic acid

A

methotrexate

44
Q

Which enzyme is inhibited by methotrexate

A

dihydrofolate reductase

45
Q

Function:

Methotrexate

A

Competitively inhibits dihydrofolate reductase from synthesizing tetrahydrofolate. Thus, dihydrofolic acid polyglutamate accumulates in the tissues

46
Q

Why are sulfonamide drugs selective for prokaryotes?

A

Sulfonamide drugs are para-aminobenzoic acid analogues. They block dihydropteroate synthetase from converting PABA into folic acid. Humans lack the ability to convert PABA into folic acid. Their folate is accquired from the diet. Thus, sulfonamide antibiotics selectively kill bacteria.

47
Q

Function:

Sulfonamide antibiotics

A

prevent bacterial replication by blocking the dihydropteroate synthesase conversion of PABA to folic acid.

48
Q

Treatment of choice for early (

A

Methotrexate

49
Q

Rescue therapy for cancer patients receiving MTX and other types of chemotherapy

A

Folinic acid (leucovorin)

Leucovorin can be used to synthesize purines and thymidylate without first being converted by DHF.

50
Q

List the 8 drugs that can increase the risk of osteoporosis.

A

Aromatase inhibitors-Decrease estrogen
Medroxy progesterone-Decrease estrogen
GnRH agonists-Decrease testosterone and estrogen
Anticonvulsants (CYP450 inducers: phenobarbital, phenytoin, carbamazepine)- Increase Vit D catabolism
Proton pump inhibitors-Decrease calcium absorption
Glucocorticoids-Decrease bone formation
Unfractionated heparin-Decrease bone formation
Thiazolidinediones-Decrease bone formation

51
Q

Which receptor types use Gs, Gq & Gi 2nd messenger systems?

A

Q=alpha-1, M1, M3, H1, V1
S=beta-1, beta-2, D1, H2, V2
I=alpha-2, M2, D2

Kiss (Qiss) and kick (qiq) until you are sick (siq) of super quinky sex (sqs). [a,b,m, d, h, v]

52
Q

How would the log dose-response curve be affected if a reversible competitive antagonist were added to a pure agonist?

A
  1. Right shift: the pure agonist drug would need to be present in higher concentrations to reach the same efficacy (ED50)
  2. Potency (or height) of the log dose-response curve would be unaffected (Emax)
53
Q

Clinical Manifestation:

Atropine poisoning (mneumonic)

A

“Blind as a bat, mad as a hatter, red as a beet, hot as a hare, dry as a bone, the bowel and bladder lose their tone, and the heart runs alone.”

Step 1 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions