Chapter 8 Flashcards
What is the spectrum of organisms that antibiotics and antiinfectives are effective against?
Bacteria, protozoa, rickettsia, amoebas, and spirochetes
Are antibiotics and antiinfectives effective against either fungal or viral infections?
NO
Common fungal infections
Pseudomembraneous candidiasis
Erythemateous candidiasis
What are some antifungal agents?
Nystatin (Mycostatin, Nilstat)
Imidazoles
What are some Imidazoles?
Clotrimazole (Mycelex)
Ketoconazole (Nizoral)
Fluconazole (Diflucan)
This antifungal agent is for systemic infection?
Diflucan
This antifungal agent is for localized infection?
Nystatin
Other antifungal agents
Amphotericin B
Griseofulvin
Mechanism of action for Nystatin
Binding sterols in the fungal cell membrane
Nystatin
Not absorbed from mucous membrane or intact skin
Poorly absorbed from GI tract
Excreted unchanged in the feces
Fungicidal and fungistatic
Higher doses or Nystatin
Nausea, vomiting, and diarrhea
How is Nystatin administered?
Topically or orally: Little absorption occurs
What is Nystatin used for?
Both treatment and prevention of oral candidiasis in susceptible cases
Can be cariogenic
Nystatin
Imidazoles useful in dentistry
Clotrimazole (Mycelex)
Ketoconazole (Nizoral)
Other Imidazoles:
Fluconazole (Diflucan)
A synthetic antifungal agent
Clotrimazole
Availability of Clotrimazole
Oral lozenge and topical cream
Mechanism of action for Clotrimazole
Alteration of cell membrane permeability
Spectrum of action of Clotrimazole
Primarily against the Candida species
Adverse reactions of Clotrimazole
Involves the GI tract; produce elevated liver enzyme
Ketoconazole
Alters cellular membranes and interferes with intracellular enzymes
Pharmacokinetics for Ketoconazole
Requires acidic environment
Uses for Ketoconazole
Treatment of mucocutaneous and oropharyngeal candidiasis
Adverse reactions of Ketoconazole
Nausea, vomiting, hepatotoxicity; react with warfarin
Fluconazole
Prevents synthesis of ergosterol in cell membranes
Fluconazole is used for the treatment of..
Oropharyngeal and esophageal candidiasis Systemic fungal infections Vaginal candidiasis Prophylactically in immunocompromised Non-responsive candidal infections
Variety of formulations available for anti-fungal medications
Tablets, Aqueous suspension, Ointment, Cream, Powder, Lozenge
Common viral infections
Herpes Labialis
Recurrent herpes simplex
Antiviral agents for herpes simplex
Acyclovir (Zovirax)
Docosano 10% (Abreva)
Penciclovir (Denavir)
Famciclovir (Valtrex)
Antiviral agents for AIDS
Nucleoside reverse transcriptase inhibitors
Nonnucleoside reverse transcriptase inhibitors
Protease inhibitors
Combinations
Other antiviral agents
Adverse reactions of Acyclovir
Topical; burning, stinging, or mild pain
Headache Sore throat
CNS Lymphadenopathy
GI effects Thrombophlebitis
Anorexia Edema
Funny taste Muscle cramps
Acne Leg pain
Accelerated hair loss Palpitation
Menstrul abnormalites
Arthralagia
Fever
Uses of Acyclovir
Limited non-life threatening initial and recurrent mucocutaneous herpes simplex virus 1 and 2 (HSV-1 and HSV-2) in immunocompromised persons
Docosanol 10% (Abreva)
Avaliable topically
Avaliable without prescription
Reduce healing time by 1/2 day
Penciclovir (Denavir)
Reduces both the duration of the lesion and the pain of the lesions
Advantages of Penciclovir (Denavir)
Higher concentration within cell
Drug duration in cells is longer
Herpes simplex: Famciclovir and Valacyclovir
Famciclovir (Prodrug) > penciclovir
Valacyclovir (Prodrug) > acyclovir
Uses of Famciclovir and Valacyclovir
Treatment of recurrent episodes of genital herpes
Treatment of acute localized varicella-zoster infections
Acquired immunodeficiency syndrome
Nucleoside reverse transcriptase inhibitors (NRTIs)
Nonnucleoside reverse transcriptase inhibitors (NNRTIs)
Protease inhibitors
Fusion/entry inhibitors
Integrase inhibitors
Azidothymidine (AZT) > Nucleoside Reverse transcriptase inhibitors Zidovudine
Well absorbed orally Metabolized by the liver Excreted by the kidneys Inhibits HIV synthesis Reduces the morbidity
Toxicity of Zidovudine
Related to bone marrow depression
CNS effects of Zidovudine
Headache, agitation, and insomnia
Oral manifestations of Zidovudine
Taste perversion, edema of the tongue, bleeding gums, and mouth ulcers
Can inhibit AZTs metabolism and potentiate the toxicity of both drugs
Acetaminophen, indomethacin, and aspirin
This non nucleoside reverse transcriptease inhibitors is specific for HIV-1
Nevirapine
Nonnucleoside reverse transcriptease inhibitors Nevirapine
These agents inhibit the same enzymes as the nucleoside analogues but do not require bioactivation
Adverse reactions of nonnucleoside reverse transcriptease inhibitors Nevirapine
CNS effects
Rash
GI effects
Elevated liver function tests
Interferes with the action of the HIV infected cells
Saquinavir
Adverse reactions of Saquinavir
Rash hyperglycemia paresthesia GI effects buccal mucosal ulceration
Fusion/Entry inhibitors
Block the progression from HIV infection to AIDS
Integrase inhibitors
Designed to block or inhibit the action of integrates, which is a viral enzyme that inserts the viral genome into the DNA of the host cell
Highly Active Antiretroviral Therapy (HAART)
Cocktails = 3 drugs
> A nucleoside
> A nonnucleoside reverse transcriptease inhibitor
> A protease inhibitor
Nucleoside analogues
Didanosine (ddl) (Videx)
Zalcitabine (ddC) (Hivid)
Zidovudine (AZT, ZVD) (Retrovir)
Nonnucleoside analogues
Delavirdine (Rescriptor)
Nevirapine (NVP) (Viramune)
Protease inhibitors
Indinavir (Crixivan)
Nelfinavir (Viracept)
Ritonavir (Norvir)
Saquinavir (Invirase, Fortovase)
Adverse effect associated with drugs used to treat HIV
Bone marrow suppression, leading to anemia and thrombocytopenia (decrease in the number of platelets) This may lead to bleeding gingiva and ulcers
Chronic hepatitis
Lasts for more than 6 months
Inflammation in the liver
Present with no symptons or very few
Symptoms of chronic hepatitis
Jaundice
Anorexia
Malaise
Interferons
Antiviral, cytotoxic, and immunomodulating action
Adverse reactions; Interferons
Myalgias Fatigue Headache Arthralgia CNS effects; Fatigue, fever, headache, depression, chills GI effects; Nausea, vomiting, diarrhea Rash Reactivation of herpes labials Excessive salivation
