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Flashcards in Antiinfectives Deck (36):

Penicillin Overview

MOA: inhibits bacterial wall synthesis
Indications: streptococcus and staphylococcus infections
Contraindications: drug allergy
Adverse Effects: allergic reaction in 0.7-4%, nausea, vomiting, diarrhea
Interactions: aminoglycosides, NSAIDs, oral contraceptives (reduce effectiveness- use different form of BC), warfarin


Nursing Considerations for Penicillin

Determine if patient is allergic to drug
Educate them about decreased effectiveness of birth control
Take drug with food to decrease GI upset
Finish entire course of antibiotics to reduce antibiotic resistance (no longer effective for MRSA)


Penicillin Key Drugs

penicillin G: given IV or IM, treats STD syphillis
amoxicillin: very common, treats infections in ears, nose, throat, GU tract, skin, and skin structures


Cephalosporin Overview

MOA: interfere with bacterial wall synthesis
Indications: effective BROAD spectrum antibiotic (covers both G+ and G- bacteria-- makes it a good drug to start treating infection before lab results come back)
Contraindication: allergy to Penicillins
Adverse Effects: diarrhea, abdominal cramps, rash, edema
Interactions: alcohol, antacids (decrease oral absorption), oral contraceptives


Nursing Considerations for Cephalosporin

Determine if patient is allergic to penicillin, because of the potential for cross-susceptibility.
Wait two hours after taking antacid to take cephalosporin.
Use different BC method


Cephalosporin Key Drugs

cefazolin: prophylaxis in surgery to prevent surgical infection
cephalexin: streptococcus and staphylococcus infections (oral)
cefoxitin: abdominal surgeries d/t effectiveness against abdominal organisms
ceftriaxone: long acting; treats meningitis d/t ability to cross BBB, also be given IM (can be a painful injection, but may only need one dose!)


Macrolide Overview

MOA: bacteriostatic drugs which inhibit protein synthesis
Indications: wide variety of infections (somewhat broad spectrum)
Contraindications: known drug allergy
Adverse Effects: GI related- especially nausea and vomiting with bad diarrhea ***excel at bad GI effects
Interactions: competitive with many drugs because it is highly protein bound and metabolized in the liver


Nursing Considerations for Macrolides

Stay hydrated, do not drink alcohol, take with food to help the GI effects, take first dose at home (to see how it effects you), no juice (because it is acidic and can contribute to GI effects)


Macrolide Key Drugs

erythromycin: respiratory and GI infections (but a lot of patients cannot tolerate GI effects), topical for dermatological use
azithromycin: upper and lower respiratory infections (Z PACK)
clarithromycin- GU and respiratory infections


Overview of Tetracyclines

MOA: inhibit protein synthesis in susceptible bacteria
Indications: treatment of acne in adolescents and adults (most common use); but also, treatment of Chlamydia, Mycoplasma, & Rickettsia
Contraindications: avoid in pregnant and nursing women (potential for birth defects), and children younger than 8 years old (discoloration of teeth and reduction of tooth enamel)
Adverse Effects: photosensitivity, GI upset, hematologic abnormalities
Interactions: antacids, dairy products, calcium, enteral feedings, and iron preparations (reduce oral absorption)


Nursing Considerations for Tetracyclines

Use SUN PROTECTION, almost better off not going into the sun
Make sure patient is not pregnant or breast feeding
Schedule monthly blood work
Take milk, calcium, and iron at least two hours apart from medication!


Tetracycline Key Drugs

doxycycline: very common, treats Rickettsial infections, chlamydial infections, and mycoplasmal infections. Also used in treatment of acne-- make sure to educate patients on adverse effects


Overview of Aminoglycosides

MOA: prevent protein synthesis in bacteria
Indications: serious infections due to toxicity
Contraindications: not for use in pregnant women d/t crossing placenta (potentially causes congenital deafness)
TOXICITIES: nephrotoxicity, ototoxicity, neurotoxicity
Interactions: other nephrotoxic drugs like vancomycin, cyclosporine & amphotericin B


Nursing Considerations of Aminoglycosides

This drug is ONLY used for SERIOUS infections because of potential adverse effects.
Watch for nephrotoxicity: Monitor I&Os, watch for increase in BUN and Creatinine, check GFR, check urine for albumin
Watch for ototoxicity: tinnitus, feeling of fullness in ears
Watch for neurotoxicity: balance issues, paresthesias (numbness/tingling) in arms/legs
Should get ready to stop medication and call the doctor if any of these signs or symptoms occur.
Do not restrict fluids because of possible nephrotoxicity.


Aminoglycosides Key Drugs

amikacin: treats infections which are resistant to gentamicin or tobramycin
gentamicin: most commonly used aminoglycoside; treatment of G+ and G- infections... make sure there are labs ordered to verify kidney function!


Overview of Quinolones

MOA: destroy bacteria by altering their DNA (cannot continue to replicate)
Indications: complicated UTIs, respiratory, skin, GI and bone&joint infections
Contraindications: known drug allergies
Adverse Effects: prolongation of QT interval on ECG& dangerous cardiac dysrhythmias when given with amiodarone
Interactions: antacids, calcium, magnesium, iron, zinc, or sucralfate-- reduce oral absorption


Nursing Considerations for Quinolones

Monitor heart rate and rhythm, watch ECG.
Clarify doctors orders if prescribed with amiodarone.
Give other meds that reduce oral absorption at least two hours apart.


Quinolones Key Drugs

ciprofloxacin: broad spectrum; effective against wide range of G- bacteria; used to treat complex UTIs; drug of choice in treatment of anthrax
Make sure it is not prescribed with amiodarone!


Miscellaneous- clindamycin

MOA: inhibits protein synthesis
Indications: treats chronic bone infections (osteomyelitis), GU tract infections, intraabdominal infections, pneumonia, septicemia, serious skin and soft-tissue infections
Contraindications: less than 1 month of age, ulcerative colitis (because of GI AE)
Adverse Effects: GI- nausea, vomiting, diarrhea


Nursing Considerations for clindamycin

Clindamycin is normally prescribed for treatment over a long period of time, which creates the potential for a super infection because it decreases the normal flora so otehr bacteria can pop up and grow.
Monitor for C. diff infection. If possible, keep normal flora up with probiotics, wash hands, good hygiene (for nurse and patient).
Take with food to help with GI- don't put hands in mouth.


Miscellaneous- metronidazole

MOA: antimicrobial
Indications: treats intraabdominal and gynecologic anaerobic infections
Adverse effects: dizziness, HA, GI discomfort, nasal congestion
Interactions: alcohol,, lithium, benzodiazepines, cyclosporine, CCBs, venlafaxine, and warfarin


Nursing Considerations for metronidazole

Avoid alcohol at all costs (at least 24 hours before or 36 hours after). Explain that it accelerates depressive effects of alcohol.
Lithium and benzodiazepines can cause an additive effect and create greater CNS depression.
In combination with warfarin, it can cause extra bleeding effects: long time to form clot, extra bruises.


Miscellaneous- vancomycin

MOA: bactericidal antibiotic
Indications: choice antibiotic for treatment of MRSA infection
Contraindications: pre-existing renal impairment and hearing loss d/t toxicities
Adverse Effects: red man syndrome, ototoxicity, nephrotoxicity
Interactions: other nephrotoxic drugs (gentamicin, amikacin, cyclosporine, amphotericin B, etc)


Nursing Considerations for vancomycin

Make sure kidney labs ordered (watch for increase in BUN and Cr+, monitor I&Os)
Have to wait for lab to come draw blood before giving vancomycin (Look at trough levels-- lowest amount in system)
Pay attention to rate at which to administer via IV infusion-- if it is infused too fast, can start flushing in head and neck (red man syndrome)


Overview of Non-HIV Antivirals

MOA: blocks enzymes that promote synthesis of new viral genomes
Indications: Herpes Simplex Virus, chickenpox, cytomegalovirus
Contraindications: severe drug allergy
Adverse Effects: specific to each drug
Interactions; CNS stimulants (additive), antibiotics (increased risk for seizures)


Nursing Considerations for Non-HIV Antivirals

Monitor for Adverse Effects:
acyclovir- nausea, diarrhea, headache, burning when topically applied
ganciclovir- bone marrow toxicity, nausea, vomiting, headache, seizures *watch for low RBC count- may have to lower/change the drug*
Educate patient on drug interactions


Non-HIV Antiviral Key Drugs

acyclovir: drug of choice for initial and recurrent herpes infections; oral, topical and injectable formulas
ganciclovir: treatment of infections caused by cytomegalovirus; dose limiting toxicity is bone marrow suppression


Overview of Antiretrovirals (HIV drugs)

Indications: active HIV infection
Contraindications: severe drug allergy or intolerable toxicity
Adverse Effects: specific to each medication
Interactions: oral contraceptives (decrease effectiveness- use other methods of BC), antivirals (increase serum levels of antiretrovirals)


Nursing Considerations for Antiretrovirals (HIV drugs)

Goal of medication is for patient to be able to take it as long as possible. If they can tolerate mild side effects, keep taking until intolerable.
Educate the patient that these drugs are NOT A CURE, they help manage symptoms by decreasing the viral load. They will be coming to the doctor frequently to monitor labs, and adapt/change drugs and dosages depending on how their body is reacting to the medications.


Antiretroviral Key Drugs

indinavir: protease inhibitor; taken in combination with other HIV drugs or alone; best absorbed if given in a fasting state
nevirapine: NNRTI; better tolerated adverse effects than other HIV drugs
zidovudine: safe in pregnant women and newborns (only retroviral that is); nucleoside reverse transcriptase inhibitor; causes bone marrow suppression- watch RBC count


Overview of Antituberculars

MOA: inhibit protein synthesis or inhibit cell wall synthesis
Indications: treatment of tuberculosis infections
Contraindications: renal and liver dysfunction
Adverse Effects: pyridoxine (vitamin B6) deficiency and liver toxicity
Interactions: antacids, seizure medications, anticoagulants


Nursing Considerations for Antituberculars

Will be taking these drugs for a long time, take FULL course so that the infection does not become resistant. (Patient compliance is very difficult because of the length of treatment)
Check labs for liver/renal function. If they are compromised, should weigh the benefits to risks. Draw baseline and monitor more frequently. Do not drink alcohol.
Take antacids two hours apart to allow full oral absorption of meds.
Increases seizure threshold, so has an additive effect with anti epileptic drugs (meaning seizures are less likely).
Increases bleeding (watch for lower BP, which could indicated internal bleeding or extra bruising)


Antitubercular Key Drugs

isoniazid: most widely used; given as single drug for prophylaxis, or in combination for treatment (with rifampin); "slow acetylator"-- genetic deficiency of specific liver enzymes (G6PD), which they need to help metabolize these drugs. This means it takes them longer to get out of the system. Start on lower dose and plan accordingly.


Overview of Antifungals

Indications: specific to each antifungal
Contraindications: liver failure, kidney failure
Adverse Effects: most commonly occur with amphotericin B treatment ("amphoterrible")
Interactions: many drugs d/t metabolism by specific liver enzymes


Nursing Considerations for Antifungals

Avoid using antifungal (even topical) in patients with renal/liver failure. Draw labs for baseline and to monitor during treatment.
Can pretreat amphotericin B with antipyretic and antiemetic to help prevent adverse effects associated with IV infusion of the drug.


Antifungal Key Drugs

amphotericin B: Drug of choice for severe systemic fungal infections (ICU setting); severe adverse effects- cardiac arrhythmias and nephrotoxicity; infusion related effects- fever, tachycardia, N/V, headache, etc.
fluconazole: good coverage against many fungal infections; better adverse effect profile than amphotericin B, oral and injectable forms