Lange: Antivirals, Antifungals, etc. Flashcards Preview

USMLE Step 1 > Lange: Antivirals, Antifungals, etc. > Flashcards

Flashcards in Lange: Antivirals, Antifungals, etc. Deck (26)
Loading flashcards...
1

Nucleoside Reverse Transcriptase Inhibitors (NRTIs)---"vudines" mostly

Activated by IC phosphorylation-->inhibit HIV reverse transcriptase-->messed up DNA synthesis-->defective viral particle Use = HIV tx Lamivudine--also used for Hepatitis B SE: neutropenia AZT-->megaloblastic anemia/BM suppression (Think of AZT as the biggest name) Didanosine-->pancreatitis

2

Nucleotide Reverse Transcriptase Inhibitors (-fovirs):

Don't need phosphorylated Also inhibit reverse transcriptase Uses = HIV and Hepatitis B infections

3

Non-Nucleoside Reverse Transcriptase Inhibitors (-vir-):

Bind specifically to reverse transcriptase-->decreased DNA synthesis Use = HIV tx SE: *Nevirapine-->Stevens-Johnson syndrome; fulminant hepatitis* *Efavirenz-->delusion and nightmares (CNS disturbances)*

4

Protease inhibitors (-navirs):

Inhibit HIV protease-->virus is unable to replicate d/t no mature proteins for core particle made Uses = HIV SE = altered body fat distribution ("Fat PiG")/hyperlipidemia

5

*Acyclovir

Viral thymidine kinase-->phosphorylates (activates) acyclovir-->dGTP analogue-->incorporates-->inhibits viral DNA synthesis Uses = HSV1, HSV2, VZV, EBV (oral hairy leukoplakia)--Herpes mostly! *SE = nephrotoxicity (via crystallization); neurotoxicity (delirium, tremor)*

6

Ganciclovir

Viral kinase-->phosphorylates (activates) ganciclovir-->guanosine analogue-->inhibits CMV DNA polymerase-->decreased CMV DNA synthesis Uses = CMV infections, especially CMV retinitis SE = pancytopenia

7

Foscarnet

Pyrophosphate analogue-->inhibits viral DNA polymerase But does not require kinase activation! Use = 2DOC for CMV infections and acyclovir-resistant HSV/VZV infections SE = nephrotoxicity (-->hypoCa and hypoMg-->szs)

8

Amantadine

Binds M2-->blocks uncoating of viral RNA Use = reduce length of influenza A symptoms Also stimulates DA release from SN (Can help tx Parkinson's) SE = CNS sx

9

Oseltamivir (-ivirs)

Inhibits Neuraminidase-->decreased viral replication/release Use = tx and prophylaxis of both influenza A and B

10

'R'ibavirin

Guanosine analogue-->inhibits viral 'R'NA polymerase-->inhibits viral 'r'eplication Uses = 'R'SV bronchiolitis

11

Amphotocerin B

Binds ergosterol-->pores (altered cell membrane permeability)-->cell death Uses = systemic mycotic infections SE = nephrotoxic (-->hypoK and hypoMg) Can-->arrhythmias Can't cross BBB, so give intrathecally for fungal meningitis

12

Nystatin

Similar MOA to Amphotocerin B More toxic so only used topically for oral and cutaneous Candida

13

Flucytosine

"FlU = 5FU" Converted into 5-FU (nucleotide analogue) inside fungal cell-->inhibits thymidylate synthase-->inhibits fungal DNA and RNA synth Use = added to amphotocerin B to combat fungal meningitis and systemic fungal infections

14

Caspofungin

*Inhibits glucan synthase*-->disrupts polysaccharide fungal cell wall Tx of systemic fungal infections

15

Ketoconazole

Inhibits fungal P450-->inhibits ergosterol synthesis Also inhibits our P450-->disrupted gonadal and adrenal steroid synth-->gynecomastia, decreased libido, etc Uses = broad-spectrum antifungal Can be given as an antifungal vaginal suppository (for vaginal candidiasis) Also used to tx Cushing syndrome

16

Fluconazole

Same as ketoconazole (inhibits P450) But doesn't affect mammal steroid synth as much! Means no gynecomastia Uses = systemic fungal infections Especially cryptococcal meningitis (Lifelong prophylaxis) and Candidal sepsis

17

Griseofulvin

Interferes with microtubule function in keratin-rich tissues-->inhibits mitosis-->inhibits fungal cell replication Uses = oral antifungal for dermatophytic fungal infections (like tinea corporis)

18

Terbinafine

Also for dermatophytic fungal infections Inhibits squalene epoxidase-->decreased ergosterol synthesis

19

Chloroquine (-quines--exception is primaquine):

Tx of Plasmodium falciparum and blood form of the others Quinine and mefloquine tx Plasmodium falciparum if it is drug resistant Quinine SE = Cinchonism (tinnitus, H/A, dizziness)

20

Pyri"meth"amine

Inhibits DHFR-->decreased DNA synthesis (Like Tri"meth"oprime) Uses = tx and prophylaxis of Plasmodium falciparum and tx of *Toxoplasma gondii*

21

Primaquine

Uses = tx hepatic forms of P. vivax and P. ovale Don't give in pregnancy (-->fetal hemolytic anemia)

22

Pentamidine

Prophylaxis for PCP (like Dapsone)

23

Nifurtimox

Tx of Trypanosoma cruzi (Chagas)

24

Suramin

Tx of early Trypanosoma brucei infections (=African sleeping sickness with recurring fever and LAD...tsetse fly)

25

Melarsoprol

Tx of late Trypanosoma brucei infections (It "sure" is nice to go to sleep. And melatonin helps with sleep.)

26

*Sodium stibogluconate

Tx of Leishmaniasis (=spiking fevers, HSM...sandfly)

Decks in USMLE Step 1 Class (97):