Presentation on theme: "Antifungal Drugs: Actions and Uses"— Presentation transcript:
1Introduction to Clinical Pharmacology Chapter 12 Antifungal and Antiparasitic Drugs
2Antifungal Drugs: Actions and Uses Fungicidal OR fungistatic: Action is related to their concentration in body tissuesUsed prophylactically to prevent fungal infection in immunocompromised patientsUsed to treat superficial and deep fungal infections; systemic infections; superficial infections of nail beds and oral, anal, and vaginal areas
3Helminthic and Protozoal Infections and Amebiasis Helminthic infections: Invasion of body by parasitic wormsAnthelmintic drugs kill the parasitesProtozoal infections: Single-cell parasitesAntiprotozoal drugs work to inhibit DNA synthesis, effectively killing the organism• Amebiasis is a parasitic gastrointestinal disorder
4Antifungal Drugs: Adverse Reactions Topical administration: Integumentary reactionsIrritation and burning sensation; redness, stinging; abdominal pain (vaginal preparations)Systemic administrationHeadache; rash; nausea; vomiting; diarrhea; anorexia and malaise; abdominal, joint, or muscle pain
5Antifungal Drugs: Contraindications, Precautions, and Interactions Contraindicated in patients with a history of allergies to the drug; during pregnancy and lactationContraindications for antifungal drugs: Griseofulvin; voriconazole; itraconazoleUsed cautiously in patients with renal dysfunction and/or hepatic impairmentInteractions possible depending on the individual drugs, and many interactions can occur
6Nursing Process: Assessment Preadministration assessment:Assess for signs of the infection before giving the first dose; take and record vital signsInspect superficial fungal infections of the skin or skin structures and recordAsk about pain and presence of white plaques or sore areas of the oral or perineal areas and any vaginal discharge
7Nursing Process: Assessment (cont.) Ongoing assessment:Carefully observe the patient every 2 to 4 hours for adverse drug reactionsIf administered topically, instruct the patient to look for signs of improvement and adverse reactions both minor and severe
8Nursing Process: Nursing Diagnosis Impaired Comfort related to IV administration of amphotericin BRisk for Ineffective Tissue Perfusion: Renal related to adverse reactions of antifungal drugs
9Nursing Process: Planning The expected outcome depends on the reason for administering the antifungal drug but includes an optimal response to therapy:Patient relates to the management of adverse reactions and has an understanding of and compliance with the prescribed treatment regimen
10Nursing Process: Implementation Promoting an optimal response therapy:Amphotericin B: Protect IV solution from exposure to light; administer immediately after the drug is reconstituted; renal damage is the most serious adverse reaction to the use of amphotericin B— hence, serum creatinine levels and BUN levels are checked frequently
11Nursing Process: Implementation (cont.) Promoting an optimal response therapy (cont.):Topical antifungal infection preparations: Inspect the area at the time of each topical application; if administered vaginally, question the patient regarding any discomfort or other sensations experienced; evaluate and chart the patient’s response to therapy daily
12Nursing Process: Implementation (cont.) Monitoring and managing patient needs:Impaired comfort: Medication administrationUse precautions when administering amphotericin B intravenously; inform before the drug is given that the side effects can be uncomfortable; provide warm blankets; reassure that the medications administered before the antifungal are to help ease the reaction
13Nursing Process: Implementation (cont.) Monitoring and managing patient needs (cont.):Risk for ineffective tissue perfusion: RenalCarefully monitor fluid intake and output, serum creatinine levels, and BUN levelsGerontologic alert: Fluconazole
14Nursing Process: Implementation (cont.) Educating the patient and family:For topical antifungal drugs include the importance of cleanliness and using the correct ointment amount in the prescribed frequency in the teaching planFor ringworm infections advise keeping towels and facecloths used for bathing separate from those of other family members
15Nursing Process: Implementation (cont.) Educating the patient and family (cont.):Teach drug-specific points for the following drugsFlucytosine; griseofulvin; ketoconazole; itraconazole; miconazole
16Nursing Process: Evaluation The therapeutic effect is achieved; signs and symptoms of infection improve; optimal skin integrity is maintainedAdverse reactions are identified, reported, and managedPatient and family demonstrate understanding of the drug regimenPatient verbalizes the importance of complying with the prescribed therapeutic regimen
17Antiparasitic DrugsAnthelmintic drugs: Used against invasion of parasitic worms (helminthiasis)Antiprotozoal drugs: Used against invasion of single-celled parasites
18Anthelmintic Drugs: Actions and Uses Albendazole: Interferes with synthesis, resulting in death of larva; used to treat larval forms of pork tapeworm and liver, lung, and peritoneum disease caused by dog tapewormMebendazole: Blocks glucose uptake by helminth; used to treat whipworm, pinworm, roundworm, American hookworm, and common hookwormPyrantel: Ability to paralyze helminth; used to treat roundworm and pinwormThiabendazole: Interrupts the life cycle of the helminth; used to treat threadworm
20Anthelmintic Drugs: Contraindications and Precautions Contraindicated in patients:With a history of hypersensitivity; during pregnancyUsed cautiously in patients:With hepatic or renal impairment; during lactation; with malnutrition or anemia
21Anthelmintic Drugs: Interactions Interactant drugEffect of interactionDexamethasoneIncreased effectiveness ofalbendazoleCimetidineInterferes with elimination of albendazoleHydantoins andcarbamazepineLower levels ofmebendazoleXanthine derivativesIncreased serum level, possible toxic effects of the xanthines
22Antiprotozoal Drugs: Actions and Uses Interfere with life cycle of the plasmodiumPrevent development of plasmodiumPrevent the mosquito from ingesting the plasmodiumUsed for the treatment of:Malaria
23Antiprotozoal Drugs: Adverse Reactions Gastrointestinal reactions:Vomiting; anorexia; abdominal cramping; diarrhea; nauseaOther body system reactions:Headache; dizziness; visual disturbances; hypotension; photosensitivity; cinchonism
24Antiprotozoal Drugs: Contraindications and Precautions Contraindicated in patients:With known hypersensitivity; during pregnancyUsed cautiously:With children; lactating patients; patients with hepatic or renal disease or bone marrow depressionQuinine not prescribed for:Patients with myasthenia gravis
25Antiprotozoal Drugs: Interactions Interactant drugEffect of interactionAntacids, ironDecreased absorption of the antimalarialDigoxinIncreased risk of digoxin toxicityBarbiturates, phenytoin, and carbamazepineDecreased effectiveness of doxycyclineWarfarinIncreased risk of bleeding
26Antiparasitic Drugs: Nursing Process: Assessment Preadministration assessment:Diagnosis of helminth infection: Examination of stool; weigh patient to determine drug dosageOngoing assessment:Save and transport all stools passed after intake of drug to laboratoryAcutely ill: Monitor vital signs; record fluid intake/output every 4 hoursObserve patient for adverse reactions
27Antiparasitic Drugs: Nursing Process: Nursing Diagnosis Diarrhea related to parasitic invasion of bodyRisk for Deficient Fluid Volume related to parasitic invasion of bodyImbalanced Nutrition: Less Than Body Requirements—adverse reaction to drug therapyRisk for Impaired Respiratory Function— adverse reaction to drug therapy
28Antiparasitic Drugs: Nursing Process: Planning Depends on the patient and the type of helminth infectionOutcome: Reduction of anxiety, optimal response to therapy, management of adverse reactions, understanding of and compliance with prescribed therapeutic regimen
29Antiparasitic Drugs: Nursing Process: Implementation Promoting optimal response to therapy:Patient and family: Explain treatment and future preventive measure; discuss concerns and questionsBased on the hospital policy, linen precaution necessary
30Antiparasitic Drugs: Nursing Process: Implementation (cont.) Monitoring and managing patient needs:Diarrhea and risk of fluid body volume deficit: Monitor fluid intake and output; IV fluid and electrolyte replacement may be necessaryRisk for imbalanced nutrition: Gastrointestinal upset causing nausea, vomiting, abdominal pain, and diarrhea; consider patient’s food preference and encourage intake of nutritious balanced mealRisk for impaired respiratory function: With inhaled treatments of pentamidine, bronchodilator may be prescribed; instruct patient and family on use
31Antiparasitic Drugs: Nursing Process: Implementation (cont.) Educating patients and family members:Instruction about taking the drugs as well as the household precautions to be followed until helminth is eliminatedPrepare the education plan to be followed
32Antiparasitic Drugs: Nursing Process: Evaluation Therapeutic effect achieved; adverse reactions identified, reported, and successfully managed; stool specimen negative for parasites; patient verbalizes an understanding of the therapeutic regimen modalities and the importance of continued follow-up testing, and complying with the prescribed regimen and preventive measures
33Question Is the following question true or false? Itraconazole is taken on an empty stomach. Therapy continues for at least 6 months until the infection is controlled.
34AnswerFalseItraconazole is taken with food. Therapy continues for at least 3 months until the infection is controlled.
35Question Is the following question true or false? A fungus is a single-celled plant that can cause yeast-like infections.
36AnswerTrueA fungus is a single-celled plant that can cause yeast-like infections. These are called fungal or mycotic infections. Antifungal drugs slow or destroy fungi.
37Question Is the following statement true or false? Superficial fungal infections to the skin, nails, and genital area are bothersome and are treated with parenteral medications.
38AnswerFalseSuperficial fungal infections to the skin, nails, and genital area are bothersome and are treated topically or by oral preparations. Systemic infections happen when the fungi gain entry into the body; these are serious infections, especially for those immunocompromised.