Brainscape's Knowledge GenomeTM

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


See full index

GI > Thomas Pharm > Flashcards

Thomas Pharm Flashcards

1
Q

5-FU

A

Given IV

Must be activated to FdUMP -> inhibits thymidylate synthase

Other actions: inhibition of RNA processing and incorporation into DNA

Combos: + Leucovorin -> enhanced TS inhibition; + Methotrexate -> enhanced 5-FU anabolism and RNA incorporation

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

Capecitabine

A

Oral version of 5-FU

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

Basic principles of oral agents

A

1) Polar sugar group provides water solubility
2) Lipophilic side group allows the drug to pass through the membranes of the gut and be absorbed orally
3) MUST BE ACID STABLE

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

Irinotecan

A

Inhibits topo I

Must be activated to SN38

Used in combo with leucovorin and 5-FU (FOLFIre)

T: diarrhea

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

Oxaliplatin

A

Synergistic with 5-FU FOLFOX (leucovorin+5-FU+oxaliplatin)

Binds DNA at promoter region of TS to overcome 5-FU resistance

Intercalates DNA

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

Erlotinib

A

Orally active epidermal growth factor receptor (EGFR)-tyrosine kinase reversible inhibitor which blocks EGFR phosphorylation and subsequent signal transduction pathways involved in proliferation, metastasis, angiogenesis, and apoptosis inhibition

Only work in pts that have activating mutation in EGFR gene

Tx: colon cancer

T: diarrhea, rash

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

Cetuximab

A

Chimeric monoclonal Ab that binds to the EGFR and inhibits proliferation, angiogenesis, metastasis, and promotes apoptosis

T: Ab-dependent cellular toxicity rxn, transfusion rxns

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

Panitumumab

A

Humanized monoclonal Ab that blocks the binding of EGF and TGFalpha ligands to the receptor

No Ab-dependent cellular toxicity rxn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Bevacizumab

A

Humanized monoclonal Ab primarily against VEGFa that inhibits its interaction with VEGF receptors -> inhibits angiogenesis in tumors and in normal tissues

Tx: colon cancer

R: shift to VEGFc or VEGFd; upreg of angiogenic factors

T: Severe HTN, hemorrhage, proteinuria, CHF, hemorrhage, gastric perforation; dose-related

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

Cisplatin

A

Produces crosslinks between adjacent guanines in DNA

Water replaces the Cl to activate the drug

T: myelosupp, N/V

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

Oxaliplatin

A

Intrastrand crosslinker

Contains platinum atom complexed with ocalate and DACH -> oxalate leaves and the bulky DACH is thought to contribute greater cytotoxicity than cisplatin

T: peripheral neuropathy

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

Mitomycin

A

Crosslinks DNA (alkylator) -> apoptosis

Tx: pancreatic, stomach, and colon cancer

T: myelosupp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Streptozocin

A

Methylnitrosurea + glucose -> glucose makes it bind to islets of Langerhans in pancreas -> specific for pancreatic cancer

Forms only the alkylating froup and not the carbamoylating group -> alkylates DNA (no carbamoylated proteins formed)

Causes lass myelosupp than other nitrosoureas (that produce carbamoylated proteins)

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

Paclitaxel

A

Binds to B-tubulin subunit of tubulin and blocks the disassembly of the microtubule bundles to prodice aberrant mictrotubule structures -> inhibits mitosis

Tx: carcinoma of the esophagus, ovary, breast, cervix, lung, and bladder

R: incr expression of p-glycoprotein POP and B-tubulin mutations

T: neutropenia and peripheral neuropathy

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

Gemcitabine

A

Inhibits DNA synthesis and is incorporated into DNA to induce apoptosis -> active against both rapidly dividing tumor cells and solid tumors

Tx: first choice agent for metastatic pancreatic cancer and esophageal cancer

T: myelosup; slowly progressive hemolytic uremic syndrome

C/I: radiation therapy

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

Vancomycin

A

Given IV; poorly absorbed orally

Binds to D-Ala-D-Ala precursor to inhibit transglycosylase

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

Teicoplanin

A

Given IV or IM; poorly absorbed orally

Inhibits peptidoglycan polymerization -> inhibits bacterial cell wall synthesis

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

Bacitracin

A

Used topically in dermatologic and ophthalmic ointments; not absorbed orallyInhibits bacterial cell wall synthesis by interfering with dephosphorylation of a lipid transport molecule which carries the building blocks of the peptidoglycan bacterial cell wall

T: nephrotoxicity if given parenterally

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

Orally absorbed PCNs

A

Penicillin V; Oxavillin; Cloxacillin; Dicloxacillin; Ampicillin; Amoxicillin; Carbenicillin indanyl

20
Q

Orally absorbed Cephalosporins

A

First generations: Cephalexin; Cefadroxil

Second generations: Cefaclor; Loracarbef

Third generation: Cefpodoxime proxetil

21
Q

Oral absorption of tetracyclines

A

Minocycline > Doxycycline > Methacycline > Demeclocycline > Oxytetra > Chlortetra (95% -> 30%)

Remain in body for a long time because of enterhepatic circulation

Doxy most widely used because of no nephrotoxicity and it’s excreted in poop

22
Q

Tigecycline

A

Not absorbed orally; parenteral use only with rapid and wide distribution into tissues

Glycycline (butyl-glycylamido derivative of minocycline)

Tx: tetracycline-resistant bacteria

23
Q

Chloramphenicol

A

Administered orally as the active drug

Effective against tetracycline-resistant bacteriaT: dose-related toxicity that presents as anemia, leukopenia, or thrombocytopenia; idiosyncratic toxicity manifested by aplastic anemia leading to fatal pancytopenia

C/I: fetuses and young kiddos because they can’t glucuronidate the drug causing gray baby syndrome (HTN, cyanosis)

24
Q

Sulfonamides

A

Competitive inhibitor of dihydropterate synthase (only found in bacteria) due to PABA analog

T: crystal urea (crystals in the bladder -> pain) in older sulfonamides

25
Q

Classes of Sulfonamides

A

1) Absorbed and excreted rapidly: Sulfisoxazole (has increased solubility -> decreased crystal urea) and Sulfamethoxazole -> only ones used in US
2) Poorly absorbed-active in bowel lumen: Sulfasalazine (used to treat colitis)
3) Topically used
4) Long-acting

26
Q

Treatment of bacterial diarrhea and antibiotics with special GI indications

A

Diarrhea is typically self limiting in young adults -> usually does NOT require treatment

Treat diarrhea in traveler’s diarrhea, neonates, elderly, and immunocompromised

27
Q

Clostridium difficile

A

Metronidazole

Discontinue all other abxs if possible

28
Q

Helicobacter pylori

A

Omeprazole + amoxicillin-clarithromycin + metronidazole

Quickly develops resistance to single abx treatment; Bismuth is also used

29
Q

TMP-SMX

A

TMP inhibits DHFR; SMX inhibits dihydropterate synthase

Sometimes used to treat diarrhea

30
Q

Ciprofloxacin or Levofloxacin

A

Used for the treatment of diarrhea

Resistant mutant forms of DNA gyrase in bacteria are increasing

T: GI distress

31
Q

Macrolides

A

Can induce GI motility -> diarrhea

Erythromycin: degraded by stomach acid

Clarithromycin: acid stable

32
Q

Telithromycin

A

Binds and inhibits 50S subunit

Ketolide that is less susceptible to methylase-mediated and efflux mediated resistance than macrolides

T: less hepatotoxicity

33
Q

Clindamycin

A

Binds to 50S subunit and inhibits translocation step; works against bacteria that are resistant to macrolides and can kill everything but C. dif

SE: produces diarrhea in up to 20% of pts that can develop into fatal pseudomembranous colitis

34
Q

Metronidazole

A

Chemically activated to form a highly reactive hydroxylamine on the nitro group which degrades DNA in ANAEROBIC organisms

*Only activated in anaerobes because they possess ferredoxin -> activates drug

Tx: Giardia; Entamoeba histolytica

T: less GI toxicity seen with Tinidazole (same MOA)

35
Q

Paromomycin

A

Luminal aminoglycoside used in combination with metronidazole

Not absorbed in intestine -> stays in intestine

Tx: Giardia; Entamoeba histolytica

36
Q

Nitazoxanide

A

Interferes with the ferredoxin oxidoreductase enzyme-dependent electron-transfer reaction which is essential in anaerobic metabolism

Tx: Cryptosporidium

No resistance; little toxicity

37
Q

Iodoquinol

A

Luminal agent that eliminates intestinal colonization of E. histolytica

Little toxicity at therapeutic doses

38
Q

Tx for Roundworms (nematodes and hookworms)

A

Benzimidazoles, mebendazole, albendazole, and ivermectin

39
Q

Tx for Flukes (trematodes)

A

Praziquantel

40
Q

Tx for Tapeworms (cestodes)

A

Praziquantel

41
Q

Benzimidazoles

A

Thiabendazole; Mebendazole; Albendazole

Inhibit microtubule polymerization by binding to parasite B-tubulin

Not toxic

42
Q

Praziquantel

A

Causes influx of calcium to produce paralysis of the musculature of the worm

T: dose-related transient abdominal distress

43
Q

Ivermectin

A

Causes tonic paralysis of the worm musculature by activating glutamate-gated chloride channels

Well tolerated

44
Q

Tx for HepB

A

Better to get vaccine!

All drugs are inhibitors of the DNA polymerase/reverse transcriptase

Adefovir dipivoxil: most widely used; also a DNA chain terminator; T: nephro- and hepatotoxic

Lamivudine: anti-HIV and HepB

Tenofovir: also a DNA chain terminator; anti-HIV and HepB

Entecavir: anti-HIV and HepB

Telbivudine: also a DNA chain terminator; competes with natural TTP of HepB

45
Q

Tx for HepC

A

IFNalpha: inhibits viral replication and the translation steps of viral protein synthesis; combo with ribavirin -> 40% response rate; SE: acute influenza-like syndrome several hours after injection

Sofosbuvir: nucleotide analog inhibitor of RNA polymerase; SE: fatigue and headache; 95% cure rate; expensive

Simeprevir: non-covalently binds to and inhibits NS3/4A protease (critical in life cycle); primarily metabolized by hepatic CYP3A and inhibits CYP1A2 and intestinal CYP3A; SE: rash, pruritus, nausea; expensive

46
Q

Tx for HepA

A

Vaccine!

GI (2 decks)

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