Antifungals and antivirals LO 12 Chapter 8 Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Antifungals Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Fungal infections Oral candidal infections; caused by Candida Albicans. Usually superinfection after antibiotic treatment for a primary infection. Under dentures, esp. ill fitting dentures In immune-compromised patients: due to corticosterids, immuno-suppressants, chemotherapy Treatment: -nystatin (Candistatin, Mycostatin)(oral suspension) -ketoconazole (Nizoral) tablets -clotrimazole troches (Canesten) -fluoconazole (Diflucan) tablets Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Nystatin Fungicidal and fungostatic against a variety of fungi, including Candida albicans Not absorbed if administered orally or applied topically. Safe to use for infants and during pregnancy. First choice in antifungal therapy. Treatment and prevention of oral candidiasis: Aqueous suspension containing sucrose(OHI): 100.000U/ml. Rinse for 2 min. and spit, with 5ml(1tsp) qid. For children use 2.5 ml For 2 weeks, longer if immunocompromised Canadian National Institute of Health Inc.

Imidazoles:Ketoconazole(Nizoral) Wide spectrum antifungal needs acidic environment for its absorption (do not administer in same time with acid blocking medication) Adverse reactions: nausea, vomiting, hepatotoxicity Teratogenic, excreted in the breastmilk Drug interactions: acid reducing drugs(wait 2 hours), alcohol(disulfiram-like reaction), contraceptives Canadian National Institute of Health Inc.

Imidazoles:Ketoconazole Dental use: in treatment and prophylaxis of oral candidiasis. Because of its side effects should be used only after topical antifungal agents have been ineffective or are believed to be ineffective Dose: 200 mg qd, for at least 2 weeks Topical : 2% cream, applied 1 or 2 times daily for 2 weeks Canadian National Institute of Health Inc.

Imidazoles:Clotrimazole Synthetic antifungal agent, primarily against Candida species Oral use: Lozenges: dissolve in saliva in ~15-30 min maintain a salivary concentration sufficient to inhibit Candida for 3 hrs. Side effects: xerostomia: difficulty dissolving Contains sucrose: OHI Dose: 1 lozenge(10mg) 5 times daily for 2 weeks Canadian National Institute of Health Inc.

Imidazoles: Fluconazole Treatment of oropharingeal and esophageal candidiasis and serious systemic candidal infections Prophylaxis of candidiasis in immunocompromised patients Treatment of candidal infections that do not respond to other agents. Dose: 200mg first day, then 100mg daily. Tablets. Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Anti-virals Canadian National Institute of Health Inc.

Viral infections in dentistry Herpex Simplex: Acyclovir Penciclovir Famciclovir Abreva AIDS(aquired immunodeficiency syndrome): -Nucleoside reverse transcriptase inhibitors(NRTIs) -Nonnucleoside reverse transcriptase inhibitors(NNRTIs) -Protease inhibitors -combinations Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Definitions Nucleoside:result from the breakdown of the nucleotides Nucleotides: A,G,C,T; are the building blocks for synthesis of DNA Reverse transcriptase=DNA polymerase Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Herpex simplex Type 1: “cold sores” Type 2:herpes genitalis Recurrent infection that might be triggered by factors that reduce general immunity: common cold, dental appointments, menstrual cycle, hot/cold weather, fever, sun exposure, etc. Treated with antiviral agents. Most antiviral agents act on viral DNA and inhibit DNA synthesis. Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Acyclovir Spectrum: herpex simplex type 1(HSV-1) type 2(HSV-2) varicella-zoster Epstein-Barr (infectious mononucleosis) Cytomegalovirus Routes of administration: Topical Oral Parenteral Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Acyclovir Adverse reactions: topical use: local burning, stinging, itching or skin rash oral use: CNS: headache, vertigo, fatigue, dizziness, insomnia, irritability GI tract: Nausea, vomiting, diarrhea, funny taste parenteral use: irritation at injection site, symptoms of encephalopathy: lethargy, seizures, confusion Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Acyclovir Uses: Topical and oral acyclovir The available data does not support the use of acyclovir for management of herpes labialis in dentistry in immunocompetent patients. No acyclovir products are approved for treatment of recurrent herpes labialis in the immunocompetent patient. Cream can be used to treat herpetic whitlow. Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. AIDS Produced by the human immunodeficiency virus (HIV) Patients usually are prone to opportunistic infections like: -tuberculosis, herpes infections, Candida infections, pneumonia. They might be taking also antiinfective agents for treatment of these infections Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. AIDS Treatment: Several drugs“cocktails” usually one from each of the following groups: -nucleoside reverse transcriptase inhibitors(NRTIs): AZT Adverse reactions: . Nausea, bone marrow depression leading to anemia, granulocytopenia and thrombocytopenia=> Transfusions are often required. *Oral effects: taste alteration, edema of the tongue, bleeding gums, mouth ulcers, pigmentation. -non-nucleoside reverse transcriptse inhibitors(NNRTIs): if used alone will develop resistance easily. -protease inhibitors: less general adverse reactions than older agents. * oral effects: buccal mucosa ulcerations. Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Other antiviral drugs amantadine, rimantadine: -prevention of influenza A or treatment to reduce the symptoms of influenza A. -in institutionalized patients (nursing homes) to prevent spread of infection during outbreaks -Side effects: nausea, dizziness, insomnia Canadian National Institute of Health Inc.

Other antiviral agents Interferons: large group of endogenous proteins with antiviral, cytotoxic and immuno-modulating actions. Are now produced by recombinant DNA technology. There are several types, classified as: alfa, beta, gamma. Only parenteral administration They interact with cells through cell surface receptors. Canadian National Institute of Health Inc.

Canadian National Institute of Health Inc. Interferons They have the following effects: -induction of gene transcription, -inhibition of cellular growth, -altered cellular differentiation, -interference with oncogene expression. Mainly in hepatitis C, multiple sclerosis. Oral side effects: -taste changes -reactivation of herpes labialis -excessive salivation Adverse reactions: flu-like syndrome, CNS effects, G.I. effects. Canadian National Institute of Health Inc.