1. Chapter 8 Antiparasitic Drug Therapy

2. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 2 Antiparasitic Therapy Millions of people worldwide are infected with protozoal organisms. Protozoa: a single-celled microorganism

3. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 3 Protozoal Illnesses Protozoal diseases are prevalent in tropical regions and in immuno- compromised hosts Exposure: international travel and immigration from areas where such infections are endemic

4. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 4 Malaria Malaria causes high morbidity and mortality Protozoa called Plasmodium  Resides in the red blood cell of humans Signs and symptoms  Fever, prostration, and recurrent chills

5. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 5 Transmission of Malaria Malaria is transmitted by the bite of a female mosquito. Malaria is also transmitted via infected blood during blood transfusions.  Has become more common in the United States

6. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 6 Treating Malaria Humans: antimalarial agents work during the asexual cycle of the parasite Mosquito: antimalarial agents do not work during the sexual cycle

7. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 7 Antimalarial Agents Quinine sulfate: action is still unknown  Declining in use because of toxic effects Mefloquine (Lariam): synthetic analogue of quinine sulfate  Used as preventive therapy and has fewer side effects (continues)

8. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 8 Antimalarial Agents Chloroquine (Aralen): safe and effective  Used for acute treatment  Fewer side effects  Given orally and intramuscularly (continued)

9. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 9 Treatment with Antimalarials Clients  Take antimalarial agents 1 to 2 weeks before travel to designated geographic areas Lab follow-up: monitor for low WBC  Note reduction in neutrophils Administer with food; causes GI irritation

10. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 10 Other Protozoal Infections Amebiasis Entamoeba histolytica  Contaminated food and drink  Signs and symptoms: diarrhea  Treatment: metronidazole (Flagyl) Trichomoniasis  Sexually transmitted disease of the vagina  Treatment: metronidazole (Flagyl)

11. Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved. 8 - 11 Antiprotozoal Agents Metronidazole (Flagyl): bactericidal, amebicidal, and trichomonacidal; it also kills some anerobic bacteria Adverse effects: N&V, convulsions, peripheral neuropathy, blurred vision, metallic taste, diarrhea, darkened urine, bone marrow depression, and rash