[4] PRELIMS | (P2) ANTIBACTERIAL & ANTI-INFECTIVES

Question 1

PULMONARY TUBERCULOSIS

ETIOPATHOGENESIS:
* Caused by ____
* Most common site for the development of TB is the ____ (____% of patients)
* Most infectious patients: those with ____ and ____
* Typical TB lesion: ____.

Answer 1

• Caused by Mycobacterium tuberculosis
• Most common site for the development of TB is the lungs (85% of patients)
• Most infectious patients: those with cavitary pulmonary disease and laryngeal TB
• Typical TB lesion: epitheloid granuloma with central caseation necrosis.

Question 2

PULMONARY TUBERCULOSIS

CLINICAL MANIFESTATIONS:
* In the Philippines, cough of ____ should lead to high index of suspicion for PTB.
* Cough may be accompanied by ____, weight loss, ____, ____, chest pain, fatigue and ____
* Absence of fever (does/does not?) exclude TB
* Physical findings are of ____ utility in PTB

Answer 2

• In the Philippines, cough of two weeks or more should lead to high index of suspicion for PTB.
• Cough may be accompanied by night sweats, weight loss, anorexia, unexplained fever and chills, chest pain, fatigue and body malaise
• Absence of fever does not exclude TB
• Physical findings are of little utility in PTB

Question 3

ANTITUBERCULAR DRUGS

DRUGS USED FOR TUBERCULOSIS
* ____ – 5 mg/kg max 300 mg
* ____ – 10 mg/kg, max 600 mg
* ____ – 25 mg/kg, max 2 g
* ____ – 15 mg/kg
* ____ – 15 mg/kg, max 1 g

Answer 3

• Isoniazid (H/INH) – 5 mg/kg max 300 mg
• Rifampicin (R) – 10 mg/kg, max 600 mg
• Pyrazinamide (Z) – 25 mg/kg, max 2 g
• Ethambutol (E) – 15 mg/kg
• Streptomycin (S) – 15 mg/kg, max 1 g

Question 4

ANTITUBERCULAR DRUGS

ISONIAZID
* Inhibits ____ synthase and ____ synthesis
* Excellent bactericidal activity against both ____ actively dividing MTB
* ____ against slowly dividing organisms

Answer 4

• Inhibits fatty acid synthase and mycolic acid synthesis
• Excellent bactericidal activity against both intracellular and extracellular actively dividing MTB
• Bacteriostatic against slowly dividing organisms

Question 5

ANTITUBERCULAR DRUGS

RIFAMPICIN

• Binds to and inhibits ____ thereby blocking ____
• Has both ____, both in dividing and non-dividing MTB
• Also has ____
• Most active ____ available and therefore ____ of first-line TB treatment

Answer 5

• Binds to and inhibits mycobacterial DNA-dependent RNA polymerase thereby blocking RNA synthesis
• Has both intracellular and extracellular bactericidal activity, both in dividing and non-dividing MTB
• Also has sterilizing activity
• Most active antimycobacterial agent available and therefore cornerstone of first-line TB treatment

Question 6

ANTITUBERCULAR DRUGS

PYRAZINAMIDE
* Exact mechanism is ____ ( ____ may be the primary target).
* More active against ____ than against actively replicating organisms
* Active only in ____ environment (pH ____) and are found within ____

Answer 6

• Exact mechanism is unclear (fatty acid synthetase-I may be the primary target.
• More active against slowly replicating organisms than against actively replicating organisms
• Active only in acidic environment (pH <6.0) and are found within phagocytes or granulomas

Question 7

ANTITUBERCULAR DRUGS

ETHAMBUTOL
* Inhibits ____ involved in cell wall synthesis, which probably inhibits the formation of ____ and ____
* ____ agent which provides synergy with other drugs
* ____ potent against MTB

Answer 7

• Inhibits arabinosyltransferases involved in cell wall synthesis, which probably inhibits the formation of arabinogalactan and lipoarabinomannan
• Bacteriostatic antimycobacterial agent which provides synergy with other drugs
• Least potent against MTB

Question 8

ANTITUBERCULAR DRUGS

STREPTOMYCIN
* Inhibits ____ by binding at a site on ____
* ____ against dividing MTB but has only ____ activity

Answer 8

• Inhibits protein synthesis by binding at a site on 30S mycobacterial ribosome
• Bactericidal against dividing MTB but has only low-level early bactericidal activity

Question 9

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory I
* New PTB (____ or ____)
* New extra-PTB (bacteriologically-confirmed or clincally-diagnosed), except ____

Answer 9

• New PTB (bacteriologically-confimrmed or clinically diagnosed)
• New extra-PTB (bacteriologically-confirmed or clincally-diagnosed), except CNS/bones or joints

Question 10

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory I
* Initial Phase - ____
* Continuation Phase - ____

Answer 10

• Initial Phase - 2 HRZE
• Continuation Phase - 4 HR or 4 HRE

Question 11

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory Ia
* New extra-PTB (____)

Answer 11

• New extra-PTB (CNS/bones or joints)

Question 12

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory Ia
* Initial Phase - ____
* Continuation Phase - ____

Answer 12

Treatment Regimen for PTB - Catergory Ia
* Initial Phase - 2 HRZE
* Continuation Phase - 10 HR

Question 13

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory II

• Pulmonary or extra-pulmonary, previously treated ____ (whether bacteriologically-confirmed or clinically-dIagnosed), except ____
• Relapse
• Treatment after failure
• ____ (TALF)
• ____ (PTOU)

Answer 13

• Pulmonary or extra-pulmonary, previously treated drug-susceptible TB (whether bacteriologically-confirmed or clinically-diagnosed), except CNS/bones or joints
• Relapse
• Treatment after failure
• Treatment after Lost to Follow-Up (TALF)
• Previous Treatment Outcome Unknown (PTOU)

Question 14

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory II
* Initial Phase - ____
* Continuation Phase - ____

Answer 14

Treatment Regimen for PTB - Catergory II
* Initial Phase - 2 HZRES and 1 HRZE
* Continuation Phase - 5 HRE

Question 15

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory IIa
* Extra-PTB (____), previously treated, drug susceptible TB (wheter bacteriologically-confimred or clnically diagnosed)

Answer 15

• Extra-PTB (CNS/bones or joints), previously treated, drug susceptible TB (wheter bacteriologically-confimred or clnically diagnosed)

Question 16

ANTITUBERCULAR DRUGS

Treatment Regimen for PTB - Catergory IIa
* Initial Phase - ____
* Continuation Phase - ____

Answer 16

• Initial Phase - 2 HRZES and 1 HRZE
• Continuation Phase - 9 HRE

Question 17

ANTITUBERCULAR DRUGS

DRUG-RESISTANT TB
* Standard Regimen Drug-Resistant (SRDR) - ____ or ____
* ____ - exclusively drug-resistant TB
* Alternate TB Treatment Regimen - individualized based on ____ and ____

Answer 17

• Standard Regimen Drug-Resistant (SRDR) - rifampacin-resistant or multi-drug resistant TB
• XDR TB Regimen - exclusively drug-resistant TB
• Alternate TB Treatment Regimen - individualized based on previous treatment courses and drug sensitivity testing

Question 18

ANTITUBERCULAR DRUGS

Side Effects and Management - Rifampacin
* Gastrointestinal intolerance - give medication at ____
* ____ urine - reassure the patient
* Flu-like symptoms (e.g., fever, muscle pain) - give ____
* ____ - discontinue and refer

Answer 18

• Gastrointestinal intolerance - give medication at bed time
• Orange/Red-colored urine - reassure the patient
• Flu-like symptoms (e.g., fever, muscle pain) - give anti-pyretics
• Thrombocytopenia, anemia, and shock - discontinue and refer

Question 19

ANTITUBERCULAR DRUGS

Side Effects and Management - Pyrazinamide
* Arthralgia due to ____ - give ____; if symptoms persist, consider ____

Answer 19

• Arthralgia due to Hyperuricemia - give aspirin or NSAID; if symptoms persist, consider gout

hyperuricemia - high uric levels in blood

Question 20

ANTITUBERCULAR DRUGS

Side Effects and Management - Isoniazid
* Burning sensation in feet (____) - give ____ (vitamin B6) ____ daily for treatment; ____ daily for prevention
* ____ - discontinue and refer

Answer 20

• Burning sensation in feet (peripheral neuropathy) - give Pyridoxine (vitamin B6) 100-200 mg daily for treatment; 10 mg daily for prevention
• Psychosis and convulsion - discontinue and refer

Question 21

ANTITUBERCULAR DRUGS

Side Effects and Management - Streptomycin
* Pain at injection site - apply ____
* Hearing impairment, ____, and dizziness due to damage of ____ - ____ and refer

Answer 21

• Pain at injection site - apply warm compress
• Hearing impairment, tinnitus, and dizziness due to damage of CN VIII - discontinue and refer

Question 22

ANTITUBERCULAR DRUGS

Side Effects and Management - Any Kind of Drug
* Mild skin reactions - give ____
* ____ - discontinue anti-TB drugs and refer
* Jaundice due to ____ - discontinue anti-TB and defer; if symptoms subside, ____

Answer 22

• Mild skin reactions - give antihistamines
• Severe skin rash (hypersensitivity) - discontinue anti-TB drugs and refer
• Jaundice due to hepatitis - discontinue anti-TB and defer; if symptoms subside, resume treatment and monitor clinically

Question 23

ANTITUBERCULAR DRUGS

Side Effects and Management - Ethambutol
* Impairment of visual acuity and color vision due to ____ - discontinue ethambutol and refer to an ____

Answer 23

• Impairment of visual acuity and color vision due to optic neuritis - discontinue ethambutol and refer to an ophthalmologist

Question 24

ANTITUBERCULAR DRUGS

Side Effects and Management - Streptomycin and Rifampicin
* ____ due to renal disorder - discontinue and refer

Answer 24

• Oliguria or albuminuria due to renal disorder - discontinue and refer

Question 25

# ANTIFUNGAL DRUGS Signs and Symptoms of Fungal Infection (4)

Answer 25

* Skin rash * Skin lesions * Nail bed infection * Oral thrush

Question 26

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AMPHOTERICIN B** * Binds to ____, a major component of fungal cell membranes. * Forms ____ that alter membrane stability and allow leakage of cellular contents * Indications: ____, initial treatment for ____ (e.g. ____, Histoplasma capsulatum, ____) * Adverse effects: Chills and fever, ____ (irreversible)

Answer 26

* Binds to **ergosterol**, a major component of fungal cell membranes. * Forms **amphotericin pores** that alter membrane stability and allow leakage of cellular contents * Indications: **topical infections**, initial treatment for **severe fungal infections** (e.g. **Candida albicans**, Histoplasma capsulatum, **Cryptococcus neoformans**) * Adverse effects: Chills and fever, **impaired renal function** (irreversible)

Question 27

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AZOLES** * Includes: (6) * Inhibit the ____ of ____ to ____ in fungal membranes * ____-spectrum antifungals.

Answer 27

* Includes: I**traconazole, Ketoconazole, Miconazole, Fluconazole, Clotrimazole, Voriconazole** * Inhibit the **cytrochrome P-450-mediated sterol demethylation** of **lanostero** to **ergosterol** in fungal membranes * **Broad-spectrum** antifungals.

Question 28

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AZOLES (Itraconazole)** * Replaced ____ for the treatment of all mycoses * Used ____ for ____, and ____ or as a shampoo for ____ * Drug of choice (DOC) for ____ * Inhibition of ____ metabolism (CYP3A4) increases or decreases metabolism of many drugs leading to toxicity * Side effects: ____, itching, rashes, ____

Answer 28

* Replaced **ketoconazole** for the treatment of all mycoses * Used **topically** for **dermatophyte infections**, and **mucocutaneous candidiasis** or as a shampoo for **seborrheic dermatitis** * Drug of choice (DOC) for **disseminated blastomycosis** * Inhibition of **cytochrome P-450** metabolism (CYP3A4) increases or decreases metabolism of many drugs leading to toxicity * Side effects: **gastric upset**, itching, rashes, **headache**

Question 29

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AZOLES (Miconazole and Clotrimazole)** * For ____ * Used in ____ ( ____, ringworm, and ____)

Answer 29

* For **topical application** * Used in **dermatophyte infections** (**tinea pedis**, ringworm, and **cutaneous and vulvovaginal candidiasis**)

Question 30

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AZOLES (Nystatin)** * Used topically for ____ infections of the skin, ____ and ____

Answer 30

* Used topically for **Candida** infections of the skin, **mucous membranes** and **intestinal tract**

Question 31

# ANTIFUNGAL DRUGS **Drugs that Affect Fungal Membranes - AZOLES (Fluconazole)** * Useful for ____ * Penetrates CSF (DOC for ____ and ____) * Inhibits ____ and ____ * Adverse effects: nausea, vomiting, ____, and reversible ____

Answer 31

* Useful for **oropharyngeal and systemic candidiasis** * Penetrates CSF (DOC for **cryptococcal meningitis** and **disseminated histoplasmosis**) * Inhibits **CYP3A4** and **CYP2C9** * Adverse effects: nausea, vomiting, **diarrhea**, and reversible **alopecia**

Question 32

# ANTIFUNGAL DRUGS **Other Antifungal Agents - Flucytosine** * Actively transported into fungal cells and is converted to ____ and subsequently to ____, which inhibits ____ and thus pyrimidine and nucleic acid synthesis * Resistance develops ____, rarely used as a single drug but is often used in combination with ____. * Relatively ____ * Adverse effects: ____ (at high doses); ____ administration can limit bone marrow effects.

Answer 32

* Actively transported into fungal cells and is converted to **5-fluorouracil** and subsequently to **5-fluorodeoxyuridylic acid**, which inhibits **thymidylate synthetase** and thus pyrimidine and nucleic acid synthesis * Resistance develops **rapidly**, rarely used as a single drug but is often used in combination with **other antifungal drugs**. * Relatively **nontoxic** * Adverse effects: **Depression of bone marrow function** (at high doses); **Uracil** administration can limit bone marrow effects.

Question 33

# ANTIPARASITIC DRUGS **Agents Active Against Amebiasis** * The major infecting organism is ____, which is ingested in ____ form, divides in the ____, and can invade the ____ to cause ____.

Answer 33

* The major infecting organism is **Entamoeba histolytica**, which is ingested in **cyst** form, divides in the **colon**, and can invade the **intestinal wall** to cause **severe dysentery**.

Question 34

# ANTIPARASITIC DRUGS **Metronidazole and Tindazole** * Metronidazole and Tindazole are used for ____ as for ____. They are also active agents ____ (formerly G. lamblia) and ____. * ____ shows activity against many anaerobic bacteria * Adverse effects: ____ (avoid with alcohol), ____ (avoided during the first trimester of pregnancy)

Answer 34

* Metronidazole and Tindazole are used for **intestinal amebiasis** as for **amebic liver abscesses**. They are also active agents **Giardia intestinalis** (formerly G. lamblia) and **T. vaginalis**. * **Metronidazole** shows activity against many anaerobic bacteria * Adverse effects: **Disulfiram-like action** (avoid with alcohol), **Teratogenic effects** (avoided during the first trimester of pregnancy)

Question 35

# ANTIPARASITIC DRUGS **Malaria - Pathogenesis** * Most important parasitic disease in humans * In humans, the ____ is responsible for disease * Rupture of ____ and release of ____ present clinically as ____ of malaria * ____ are responsible for disease relapse

Answer 35

* Most important parasitic disease in humans * In humans, the **erythrocytic cycle** is responsible for disease * Rupture of **schizonts** and release of **merozoites** present clinically as **paroxysms** of malaria * **Hypnozoites** are responsible for disease relapse

Question 36

# ANTIPARASITIC DRUGS **Malaria - Etiology** * Protozoan disease caused by 4 species of ____ (____, ____, ____, and ____) and transmitted by the bite of infected ____ mosquitoes (____ in the Philippines) * ____ causes nearly all deaths and neurological complications.

Answer 36

* Protozoan disease caused by 4 species of **Plasmodium** (**falciparum**, **vivax**, **ovale**, and **malariae**) and transmitted by the bite of infected **Anopheles** mosquitoes (**Anopheles flavirostris** in the Philippines) * **Plasmodium falciparum** causes nearly all deaths and neurological complications.

Question 37

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Chloroquine + Sulfaoxine/Pyrimethamine (CQ + SP)** * Clinical Use: first line treatment in probable and confirmed ____ that is not severe * Pyrimethamine Side Effects: (3)

Answer 37

* Clinical Use: first line treatment in probable and confirmed **falciparum malaria** that is not severe * Pyrimethamine Side Effects: **megaloblastic anemia**, **pancytopenia**, **pulmonary infiltration**

Question 38

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Artemeter-Lumefantrine** Clinical Uses: * ____ line drug for cases which did not respond to adequate ____ * Not recommended for ____ and ____

Answer 38

* **Second line** drug for cases which did not respond to adequate **CQ + SP therapy** * Not recommended for **pregnant women** and **children < 8 y/o**

Question 39

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Artemeter-Lumefantrine** Side Effects: * Artemether - (3) * Lumefantrine - ____

Answer 39

* Artemether - **anaphylaxis, utricaria, fever** * Lumefantrine - **none identified**

Question 40

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Quinine + Tetracycline/Doxycyline (Quinine + Clindamycin for Pregnant Women and Children < 8 y/o)** * Clinical Use: ____ line drug for those who did not response to second line regimen; drug of choice for ____ * Quinine Side Effects: ____, ____, high-tone hearing loss, ____, very bitter taste

Answer 40

* Clinical Use: **third line** drug for those who did not response to second line regimen; drug of choice for **severe malaria** * Quinine Side Effects: **cinchonism**, **tinnitus**, high-tone hearing loss, **hypoglycemia**, very bitter taste

Question 41

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Primaquine** *Clinical Use*: * Given as a single dose to confirmed ____ cases to prevent transmission * Given for ____ days to confirmed ____ to prevent relapse * The only drug which can eradicate ____ of the parasite *Side Effect*: massive hemolysis in ____

Answer 41

*Clinical Use*: * Given as a single dose to confirmed **P. falciparum** cases to prevent transmission * Given for **14 days** to confirmed **P. vivax** to prevent relapse * The only drug which can eradicate **extrahepatic stages** of the parasite *Side Effect*: massive hemolysis in **G6PD deficiency**

Question 42

# ANTIPARASITIC DRUGS **ANTIMALARIAL AGENTS - Chloroquine** * Clinical Use: drug of choice for ____ * Side Effects: nausea, ____, ____ , retinopathy (____)

Answer 42

* Clinical Use: drug of choice for **P. vivax cases** * Side Effects: nausea, **dysphoria**, **pruritus**, retinopathy (**> 100 g**)

Question 43

# ANTIPARASITIC DRUGS Drugs used for severe **Falciparum** malaria (4)

Answer 43

* Artesunate * Artemether * Quinine Dihydrochloride * Quinidine

Question 44

# ANTIPARASITIC DRUGS Drugs for Prophylaxis (2 groups)

Answer 44

* Doxycycline, primaquine, atovaquine/proguanil, chloroquine * Mefloquine (only prophylaxis permitted in pregnancy)

Question 45

# ANTIPARASITIC DRUGS **ANTIHELMINTHICS** **Agents Effective Against Nematode (Roundworm) Infections - *Albendazole and Mebendazole*** * Bind with high affinity to ____ to inhibit its polymerization and microtubule assembly. * Also irreversibly ____ by nematodes; the resulting glycogen depletion and decreased ATP production ____ the intestinal parasite, which is then cleared from the GI tract * ____ is the drug of choice for ____ and cystic hydatid disease. * Adverse effects: ____ during short term therapy. They are potentially ____.

Answer 45

* Bind with high affinity to **parasite free B-tubulin** to inhibit its polymerization and microtubule assembly. * Also irreversibly **inhibit glucose** uptake by nematodes; the resulting glycogen depletion and decreased ATP production **immobilize** the intestinal parasite, which is then cleared from the GI tract * **Albendazole** is the drug of choice for **cysticercosis** and cystic hydatid disease. * Adverse effects: **GI distress** during short term therapy. They are potentially **teratogenic**.

Question 46

# ANTIPARASITIC DRUGS **ANTIHELMINTHICS** **Agents Effective Against Cestode (Tapeworm) and Trematode (Fluke) Infections - *Praziquantel*** * Causes ____ of the worm due to increased cell membrane permeability of ____ * Most effective drug against all types of ____ ( ____, ____) * Adverse effects: fever and rashes, contraindicated in ____ (host-defense induced irreversible eye damage)

Answer 46

* Causes **paralysis** of the worm due to increased cell membrane permeability of **calcium** * Most effective drug against all types of fluke **infections** (**schistosomiasis**, **paragonimiasis**) * Adverse effects: fever and rashes, contraindicated in **ocular cysticercosis** (host-defense induced irreversible eye damage)

Question 47

# ANTIPARASITIC DRUGS **ANTIHELMINTHICS** **Agents Effective Against Cestode (Tapeworm) and Trematode (Fluke) Infections - *Bithionol*** * Inhibits ____ * Alternative for ____ and as an alternative to ____ for ____

Answer 47

* Inhibits **parasite respiration** * Alternative for **Fasciola hepatica** and as an alternative to **praziquantel** for acute **pulmonary paragonimiasis**

Question 48

# ANTIVIRAL AGENTS **ANTIHERPES VIRUS DRUGS Acyclovir** * ____, requires ____ to inhibit the activity of viral DNA polymerase * ____ eradicate latent virus

Answer 48

* **Purine analog**, requires **viral thymidine kinase** to inhibit the activity of viral DNA polymerase * **Does not** eradicate latent virus

Question 49

# ANTIVIRAL AGENTS **ANTIHERPES VIRUS DRUGS Penciclovir and Docosanol** * Used as ____ to treat herpes infection. * Docosanol prevents ____ with cell membranes, thereby inhibiting viral penetration

Answer 49

* Used as **topical cream** to treat herpes infection. * Docosanol prevents **fusion with the HSV envelope** with cell membranes, thereby inhibiting viral penetration

Question 50

# ANTIVIRAL AGENTS **ANTIHERPES VIRUS DRUGS - Ganciclovir** * ____ analog that inhibits ____

Answer 50

* **Deoxyguanosine** analog that inhibits **replication of CMV**

Question 51

# ANTIVIRAL AGENTS **ANTIHERPES VIRUS DRUGS - Foscarnet** * Inhibits (2)

Answer 51

* Inhibits **viral DNA and RNA polymerase** and **HIV reverse transcriptase **

Question 52

# ANTIVIRAL AGENTS **ANTI-INFLUENZA AGENTS Amantadine and Rimantadine** * Interact with the ____ of the ____ of the virus to inhibit the uncoating and replication of the viral RNA in infected cells * Used to treat ____ (influenza A), administered within the ____, and as a prophylaxis during the season * Adverse effects: mild CNS effects ( ____, ____ ) GI dysfunction. Patients with a ____ needs close monitoring. ____ effects

Answer 52

* Interact with the **M2 protein** of the **proton channel** of the virus to inhibit the uncoating and replication of the viral RNA in infected cells * Used to treat **orthomyxovirus** (influenza A), administered within the **first 48 hours of symptoms**, and as a prophylaxis during the season * Adverse effects: mild CNS effects (**insomnia, nervousness**) GI dysfunction. Patients with a **history of seizure** needs close monitoring. **Teratogenic** effects

Question 53

# ANTIVIRAL AGENTS **ANTI-INFLUENZA AGENTS Zanamivir and Oseltamivir** * ____ inhibitors * Treatment and prophylaxis of ____. * Effective against ____ * Adverse effects: Abdominal pain and GI dysfunction ( ____ ) bronchospasm ( ____ )

Answer 53

* **Neuraminidase** inhibitors * Treatment and prophylaxis of **acute uncomplicated influenza infection**. * Effective against **both influenza A and B** * Adverse effects: Abdominal pain and GI dysfunction (**Oseltamivir**) bronchospasm (**Zanamivir**)

Question 54

# ANTIVIRAL AGENTS **ANTIRETROVIRAL DRUGS** * Act by inhibiting HIV-encoded RNA dependent DNA polymerase ( ____ ) * Combination therapy with ____ with drugs from the other classes of antiretroviral agents that reduce or prevent replication and have different modes of action is most effective. It reduce the likelihood of the ____ * Ex. (4) * Adverse Effects: (2)

Answer 54

* Act by inhibiting HIV-encoded RNA dependent DNA polymerase (**reverse transcriptase**) * Combination therapy with **NRTI** with drugs from the other classes of antiretroviral agents that reduce or prevent replication and have different modes of action is most effective. It reduce the likelihood of the **development of resistance** * Ex. Zidovudine, Didanosine, Stavudine, Lamivudine * Adverse Effects: **metabolic acidosis**, and **hepatic toxicity**