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1

fluconazole
voriconazole
miconazole
clotrimazole
ketoconazole

MOA:

Inhibit fungal enzyme (similar to CYP 450 enzymes) required for ergosterol synthesis; Inhibit synthesis of ergosterols disrupt cell membrane contents leak out/kill the fungus

2

fluconazole
voriconazole
miconazole
clotrimazole
ketoconazole

Spectrum?

All broad spectrum anti-fungal

3

fluconazole
voriconazole
miconazole
clotrimazole
ketoconazole

- Widest therapeutic index.
- Very good candida treatments anywhere in body (one dose for vaginal yeast infection)

fluconazole

4

Azole Derivative Anti-fungals

fluconazole
voriconazole
miconazole
clotrimazole
ketoconazole

5

Azole Derivative Anti-fungals Adverse Effects

- Topical preparations, well tolerated

- systemic routes
Liver toxicity (Hepatotoxicity)
Drug interactions

- Voriconazole vision issues: Abnormal vision, color vision change and/or photophobia
Optic neuritis and papilledema

6

"prazole" ending =

proton pump inhibitors in GI disorders

7

Polyene Anti-fungal Drugs

amphotericin B
natamycin
nystatin

8

amphotericin B
natamycin
nystatin

MOA:

Bind ergosterols in fungal cell membrane

causes pores to form that disrupt cell membrane

contents leak out/kill the fungus

9

Polyene Anti-fungal Drugs: Useful agent for nearly all life-threatening mycotic infections, but quite toxic

amphotericin B

10

Polyene Anti-fungal Drugs: Topical ophthalmic only – used in eye

natamycin

11

Polyene Anti-fungal Drugs: Topical creams, ointments, powders NOT used in eye; PO•Mostly used for candida oral thrush and vaginal yeast infections

nystatin

12

Adverse Effects Polyene Anti-fungals Adverse Effects: Amphotericin B

“ampho-terrible” when given IV
- High renal toxicity
- Bone marrow suppression
- Liver toxicity
- Chills, fever, headache, nausea, vomiting
- Does bind to some human sterols, which is why we see systemic toxicity

13

Adverse Effects Polyene Anti-fungals Adverse Effects: Nystatin; Natamycin

not absorbed much from skin, mucus membranes or GI tract, has very low toxicity/are well-tolerated

14

Griseofulvin:
- spectrum
- use
- MOA
- Adverse Effects

- Narrow spectrum

- used only for dermatophyte infections (skin, nail, hair)

- Require long treatments/high failure rates

MOA: inhibits fungal mitosis

Adverse Effects:
Well tolerated
Can’t take with alcohol Disulfiram-like effect– flushing, nausea, vomiting type reaction

15

Neurocysticercosis Treatment
- Drug
- MOA

- albendazole
- Binds beta-tubulin in parasite, prevents microtubule assembly. Inhibition of parasite microtubules keeps parasite from absorbing glucose for energy...parasite eventually dies.

16

Adverse Effect Albendazole

- Risk of Retinal Damage in Patients with Retinal Neurocysticercosis
**Cysticercosis may involve the retina. Before initiating therapy for neurocysticercosis, examine the patient for the presence of retinal lesions. If such lesions are visualized, weigh the need for anticysticeral therapy against the possibility of retinal damage resulting from inflammatory damage caused by albendazole-induced death of the parasite

- Bone marrow suppression
- Hepatoxicity

17

metronidazole: MOA
- oral use
- topical use

disrupts microbe DNA synthesis

- oral: Trichomoniasis sexually transmitted parasite infection; various other intestinal amoebas, parasites and anerobic bacteria

- topical: acne rosacea treatment

18

Adverse Effects Metronidazole

- Dry mouth or metallic taste in mouth
- Disulfirm-like effect
(Nausea and vomiting occur if alcohol is ingested during therapy)
- Topical: irritation of skin and eyes/tearing (don’t apply near the eyes)

19

Acanthamoeba Treatment in Eye
- Drugs
- MOA

polyhexamethylene biguanide (PHMB)
chlorhexidine
propamidine isethionate

MOA: Destabilize amoeba membranes, ultimately killing them
MOA propamidine: inhibit DNA synthesis in amoeba

20

Malaria Treatment:
- drug
- MOA

chloroquine
- causes build-up of heme, a breakdown product of hemoglobin
- Heme accumulation in rbc’s is toxic to the plasmodium parasite

21

Adverse Effects Chloroquine

- Whorl keratopathy (most common)
- Bulls-eye maculopathy
- Central visual field defects and color vision changes
- Increased risk for retinopathy

22

Toxoplasmosis Treatment for Eye

pyrimethamine
sulfadiazine

*systemic corticosteroids are an effective therapy for ocular toxoplasmosis

23

Head lice and Scabies Treatment
- Drug
- MOA

gamma-hexachlorocyclohexane

organochloride absorbed through insect exoskeleton resulting in death

24

Anti-Mycobacteria Drugs:

Rifampin
Isoniazid
Pyrazinamide
Ethambutol

25

Active disease = combination therapy

Rifampin
Isoniazid
Pyrazinamide
Ethambutol

26

Latent disease = usually monotherapy

soniazid
and/or
rifampin

27

Rifampin MOA:

Inhibits microbial transcription (thus RNA synthesis) by deactivating DNA-dependent RNA polymerase

28

Isoniazid MOA:

Inhibits mycolic acid in cell wall synthesis

29

Pyrazinamide MOA:

not really known...works on a variety of pathways including energy production and inhibiting translation and several enzymes to kill the mycobacteria – inhibits mycolic acid in cell wall too

30

Ethambutol MOA:

inhibits cell wall synthesis by inhibiting arabinosyl transferase (arabino galactin big component of cell wall)