PDA Block 3 Week 3 Flashcards
(52 cards)
1
Q
Mebendazole
A
- Immobilizes and kills parasite
- selective damage to microtubules - intestinal roundworms
- kills some ova
- poorly absorbed
- low systemic toxicity
2
Q
Albendazole
A
- immobilizes and kills parasite
- hepatic metabolite (albendazole sulfoxide) responsible for activity
- Echinococcus (Hydatid cyst)
- Cutaneous larval migrans
- metabolite well distributed
- elevated hepatic enzymes, abdominal pain, N/V, headache
3
Q
Thiabendazole
A
- Hook worm: inhibits energy metabolism, mitochonidrial fumarate reductase
- Strongyloides: blocks microtubule assembly - Strongyloides
- cutaneous larva migrans
- oral form absorbed rapidly
- N/V, dizziness
4
Q
Pyrantel pamoate
A
- Hook worm: inhibits energy metabolism, mitochonidrial fumarate reductase
- Strongyloides: blocks microtubule assembly - Strongyloides
- cutaneous larva migrans - oral form absorbed rapidly
- N/V, dizziness
5
Q
Praziquantel
A
- increases calcium permeability → muscle contraction (followed by spastic paralysis)
- schistosoma
- some activity against other trematodes
- also for Cestodes
-abdominal discomfort, nausea
6
Q
Paromomycin sulfate
A
- 3rd choice drug for Tapeworm
7
Q
Chloroquine
A
- blood schizonticide
- parasitized erythrocytes concentrate the drug ( >25 fold) by pH dependent mechanism into acidic vacuoles
- only intraerythrocytic trophozoites that are actively degrading hemoglobin are suceptible
- inhibit heme -polymerization, allowing heme to accumulate to toxic levels
- Prophylaxis: prevent attacks of all 4 species of Malaria (if they are chloroquine sensitive)
- Treatment: eradicate P, malaria and chloroquine-sensitive P, falciparum
- Target blood schizonts of P. vivax and ovale ( does not target liver hypnozoites)
- usually well tolerated
- visual impairment with extended use
8
Q
Mefloquine
A
- similar to chloroquine
- blood schizonticide -Treatment: chloroquine-resistant P. falciparum
-prophylaxis in chloroquine-resistant areas
- contraindicated in those with epilepsy or psychiatric disorders
- psychiatric effects: anxiety, paranoia, depression
- Vestibular effects: dizziness, vertigo
9
Q
Atovaquone + proguanil
A
- Block pyrimidine synthesis
- Atovaquone: selectively inhibits malarial mitochondrial electron transport (cytochrome bc1)
- Produanil: prodrug that inhibits malarial dihydrofolate reductase→ blocks folate synthesis & pyrimidine synthesis
- synergistic effects on mitochondria w/ atovaquone
- Prevention and treatment of chloroquine-resistant P.Falciparum
- N/V, diarrhea, rash
10
Q
Quinine
A
- similar to chloroquine
- blood schizonticide against all 4
- agent for severe, acute attacks
- alternate for chloroquine resistant P. Falciparum
-Cinchonism: headache, visual disturbance, dizziness, tinnitus, GI irritation, n/v. CV effects
11
Q
Doxycycline
A
- Decrease malarial protein synthesis
- depress dihydroorotate dehydrogenase activity (interferes with pyrimidine synthesis)
- effective for multidrug resistant P. falciparum
- GI disturbance: enterocolitis
- Candida superinfection in colon
- Photosensitization with rash—sunlight makes rash worse
- Teeth discoloration—avoid use in children (<8)
- Contraindicated in pregnancy
12
Q
Primaquine
A
- metabolites can act as oxidants
- kills liver hypnozoites
- radical cure or terminal prophylaxis of P. Vivax and P. Ovale
- used in conjunction with blood schizonticide (chloroquine)
- used in combo with clindamycin to treat pneumocystis jiroveci in AIDS pt
- hemolytic reactions in G6PD deficiency
13
Q
Metronidazole
A
- disrupts DNA
- Tissue amebicide for mild to severe symptomatic infections of E. hystolytica
- n.v. anorexia, diarrhea, transient leukopenia, neutropenia, thrombophlebitis after IV infusion, bacterial and fungal superinfections (candida)
14
Q
Iodoquinol
A
- unknown, effective for trophozoites in bowel lumen
- luminal amebicide
- use in combo with metronidazole for mild to severe infections of E. histolytica
- Diarrhea and other GI symotoms
- contraindicated for those hypersensitive to iondine –containing preparation
15
Q
Atovaquone
A
- Ubiquinone analog: inhibits mitochondrial electron transport →disrupts protozoal pyrimidine synthesis
-Pneumocystis jiroveci prophylaxis or treatment
- Toxoplasma gondii
(+rifabutin)
-nausea, diarrhea, vomiting, rash
16
Q
Nitazoxanide
A
- inhibits pyruvate: ferredoxin oxidoreductase (required for anaerobic energy metabolism - Giardia lamblia
- Crytposporidium parvum
-Diarrhea, nausea, abdominal pain
17
Q
Nematode (Roundworm) Rx
A
Mebendazole
Albendazole
Thiabendazole
Pyrantel pamoate
18
Q
Trematode Rx
A
Praziquantel
19
Q
Cestode Rx
A
Praziquantel
Albendazole
Paromomycin sulfate
20
Q
Malarial Rx
A
Chloroquine
Mefloquine
Atovaquone + proguanil
Quinine
21
Q
Rx: pneumocystis jiroveci
A
- Trimethoprim +Sulfamethoxazole (TMP-SMX)
- Clindamycin + Primaquine
- Atovaquone
- Dapsone
22
Q
Active Immunization
A
Vaccination (e.g. polio, smallpox, measles, influenza, herpes zoster [chickenpox,
shingles], hepatitis A, hepatitis B, rabies, etc.)
23
Q
Passive immunization
A
- Injection of immune globulin often blocks viral penetration
24
Q
Amantadine
A
- blocks viral uncoating by interfering with influenza A M2 protein (ion channel responsible for acid mediated dissociation of ribonucleoprotein complex) - Prophylaxis against influenza A but not B
- Reduces fever in 50% of pt and illness duration by 1-2 days if given within first 2 days of illness
- for last few years, influenza strains have been amantadine resistant - CNS: slurred speech, anxiety, confusion, depression, headache
- Excreted unchanged in urine→ reduce dose in renal disease
25
Oseltamivir
- Tamiflu
- inactive prodrug that is converted to oseltamivir carboxylate ( competitive inhibitor of influenza NA)
- interferes with viral release from infected cells and viral penetration into respiratory epithelium - treatment of uncomplicated influenza A and B in pt >1 yo
- must be given within 48 hours of symptom onset
- flu prophylaxis in pt > 1yo - n/v/diarrhea
- bronchitis
26
Trifluridine
- interferes with DNA synthesis; Thymidine analog
- ophthalmic Tx of kerato-conjunctivitis and recurrent epithelial keratitis due to Herpes Simplex types 1 and 2
- burning, stinging, hypersensitivity
27
Acyclovir
- inhibits DNA polymerase
- phosphorylated form is produced 40-100x faster in infected cells by herpes thymidine kinase
- inhibits herpes DNA pol 10-30x more than host cell DNA pol
- acts as a competitive inhibitor of dGTP and as a DNA chain terminator - IV: serious systemic herpes virus simplex (HSV)
- oral: primary genital herpes
- oral: primary herpetic gingiovostomatosis
- Topical: primary genital herpes (not recurrent)
- Misc: chickenpox in children - generally well tolerated
- rash, itching, n/v, headache, fatigue
28
Famciclovir
- prodrug that is converted to penciclovir which is then phosphorylated (inhibits viral DNA pol) - Acute herpers zoster (shingles) <3 dyas duration
- Tx and suppression of recurrent genital herpes
- similar to acyclovir
- rash, itching, n/v, headache, fatigue
29
Penciclovir
- inhibits DNA polymerase
- Topical: tx for recurrent herpes of the lips and face
- rash
30
Ganciclovir
- inhibits DNA pol
- phosphorylation is catalyzed by CMV protein kinase
- virustatic - Tx of CMV retinitis in AIDS pt
- CMV prophylaxis for transplant recipients
- slow progression not cure - bone marrow suppression, leukopenia, thrombocytopenia, anemia
- may enhance bone marrow suppression when given with zidovudine (AZT)
31
Foscarnet
- selectively inhibits CMV DNA pol by binding to its pyrophosphate-binding site
- Does not require conversion to triphosphate form to be active
- AIDS pt with CMV (cytomegalovirus) retinitis
- slow progression, not cure
- approved for acyclovir-resistant herpes simplex
- Renal damage (reversible)
- electrolyte imbalances
- seizure
32
Lamivudine
- nucleoside analog inhibitor of RT domain of HepB DNA pol (must be phosphorylated to be active)
- HBV
- n/v/ diarrhea
33
Tenofovir
- esterified adenosine monophosphate analog (phosphorylated to active nucleotide)→ inhibits RT domain of Hep B DNA pol
- HBV
- GI upset
34
Ribavirin
- interferes with viral mRNA synthesis
- mono-P inhibits inosine 5P dehydrogenase ( thus GTP synthesis)
- Tri-P inhibits GTP dependent capping of viral mRNA - aerosol use in infants & young children with severe lower RSV
- HCV in combo with interferon-alpha
-Aerosol: use with caution in assisted ventilation (can precipitate in respiratory equp.)
-pulmonary function deterioration, rash
IV/oral: anemia, bone marrow suppression
35
Interferon
- induce host cells to produce enzymes that block translation of viral mRNA
- approved antiviral uses for recombinant alpha interferons: Condyloma acuminata, HepB and C, PEG alfa 2a and PEG-alfa-2b in combo with ribavirin are specifically useful for HepC
- flu like syndrome
- Leukopenia, bone marrow suppression
- neurotoxicity, myalgia
36
Boceprevir
- reversible inhibitor of HepC NS3 (HCV poly protein) protease (blocks formation of infectious virus particles) - Hep C genotype 1 in combo with PEG interferon + ribavirin
- boceprevir + PEG-interferon Alpha +ribavirin
- same SE as interferon + ribavirin
- increase incidence/severity of anemia and neutropenia
- contraindicated with drugs that are CYP3A substrates or induces
37
Zidovudine
- Thymidine nucleoside analog: phosphorylated by cellular kinase
- Blocks nucleic acid synthesis by inhibiting RT
- AZT tri-P acts as a DNA chain terminator
- nucleoside RT inhibitor for HIV in adults and children
- Bone marrow suppression, neutropenia, anemia
- drugs that inhibit glucuronyl transferase (acetaminophen) increase hematologic toxicity of AZT and should be avoided
- myopathy w/prolonged use
38
Emtricitabine
- Fluorinated analog of 3TC that inhibits RT by competing for dCTP
- incorporations into DNA (chain termination)
- combo therapy for HIV infect pt
- headache, diarrhea, nausea
39
Abacavir
- nucleoside analog inhibitor of RT
- combo therapy for HIV
- hypersensitivity rxn (ass. With HLA-B*5701 antigen)
40
Efavirenz
- Non-nucleoside inhibitor of RT
- doesn’t require phosphorylation for activity
- part of multi-drug therapy for HIV
- Rash, CNS/psychiatric symptoms, nightmares
41
Lopinavir
- prevents viral protease from cleaving Gag-pol polypeptide into functional proteins
- results in non-infectious virus particles
- used in combo with RT inhibitors (HIV-1 and HIV-2)
- significantly decreases viral blood load
- Diabetes (insulin resistance)
- alterations in lipid metabolism
- fat redistribution
- alters metabolism of many other drugs (CYP3A)
- diarrhea
42
Ritonavir
- PI & Blocks metabolism of lepinavir
- Used to boost levels of PIs
- avoid other CYP3A drugs
43
Enfuvirtide
- inhibits fusion of viral and cellular membranes
- binds to gp41 subunits of HIV, blocking conformation change for membrane fusion
- used against HIV-1 ONLY
- Tx HIV infected with detectable viral replication despite ongoing therapy
- local injection site rxn
- diarrhea, nausea, fatigue
44
Maraviroc
- chemokine co-receptor (CCR5) antagonist
– prevent interaction with HIV gp 120
- Blocks entry of HIV into cells - Tx of CCR5 tropic HIV-1
- hepatotoxicity
- possible CV events (ischemia, infarction)
45
Raltegravir
- inhibits HIV-1 integrase acitivity, preventing integration of HIV-1 DNA into genome
- Tx HIV-1 new and Tx-experience
- works virus that is resitant to other drugs
- generally well-tolerated
46
RX HIV
- Zidovudine (AZT)
- Lamivudine (3TC)
- Tenofovir
- Emtricitabine (FTC)
- Abacavir
Efavirenz
- Lopinavir+ ritonavir
- Enfuvirtide
Maraviroc
Raltegravir
47
RX influenza
- Amantadine
| - Oseltamivir
48
HSV Rx
- EYE: Trifluridine
- LIPS/FACE: penciclovir & Acyclovir
- GENITAL: acyclovir & Famciclovir
- Acyclovir resistant: Foscarnet
Herpes zoster (Shingles): Famciclovir
49
CMV
- Ganciclovir
| - Foscarnet
50
RSV
- Ribavirin
51
HEP B
Lamivudine (3TC)
- Tenofovir
- interferon-alpha
52
HEP C
Ribavirin + interferon –alpha +boceprevir
