Antibiotics, Antivirals, Antifungals, NSAIDs, and Gout Medications

Antibiotic Classes

General Information

• Antibiotics are ineffective against viral infections.
• Ideally, culture suspected infection sites to identify the causative organism and its antibiotic susceptibilities before starting antibiotic therapy.

Culture and Sensitivity (C&S)

• Obtain cultures from appropriate sites BEFORE starting antibiotic therapy is ESSENTIAL.
• If C&S shows resistance to an antibiotic (abx), a different antibiotic should be used.

Nursing Implications for All Antibiotic Use Before Beginning Therapy

• Assess drug allergies and medication lists for potential interactions.
• Assess renal, liver, cardiac function, and other lab studies.
• Obtain a thorough patient health history, including immune status.
• Assess for conditions that may be contraindications to antibiotic use.
• Assess for potential drug interactions/cross-reactivities.

When Taking Antibiotics

• Instruct patients to take antibiotics exactly as prescribed and for the full prescribed length of time. They should not stop early, even if they feel better or experience expected side effects (nausea/vomiting/diarrhea).
• Monitor for signs and symptoms of superinfection (infection occurring after or on top of an earlier infection, especially following treatment with broad-spectrum antibiotics):
  • Fever, perineal itching, cough, lethargy, or any unusual discharge.
• Monitor for allergic reactions:
  • Airway/breathing problems (wheezing, difficulty breathing).
  • Urticaria/Rashes.
  • Pruritus/Itching.
• Each class of antibiotics has specific adverse effects and drug interactions that must be carefully assessed and monitored.
• The most common adverse effects of antibiotics are nausea, vomiting, and diarrhea.
• All oral antibiotics are absorbed better if taken with at least 6 to 8 oz of water.

Monitoring for Therapeutic Effects

• Improvement of signs and symptoms of infection.
• Return to normal vital signs.
• Negative culture and sensitivity tests.
• Disappearance of fever, lethargy, drainage, and redness.

Monitoring for Adverse Reactions

• Allergic reactions (rash, wheezing).
• Upset stomach, diarrhea – continue to take.

Sulfonamides

Mechanism of Action (MOA)

• Bacteriostatic (stop bacteria from reproducing but don't necessarily kill them) and work by interfering with the synthesis of folic acid in bacteria.

Works Against

• Gram + and - bacteria.

Commonly Used For Conditions Including

• UTIs
• Upper respiratory tract infections
• Outpatient Staphylococcus infections
  • SMX-TMP is commonly used because of the high rate of community-acquired MRSA infections

Common Drugs to Know

• Bactrim (Trimethoprim – Sulfamethoxazole)

CAUTION

• High risk for allergies; MONITOR for SULFA ALLERGY with use of BACTRIM
• Sulfamethoxazole combined with trimethoprim (a nonsulfonamide antibiotic), known as Bactrim, Septra, or co-trimoxazole, and often abbreviated as SMX-TMP, is used commonly in clinical practice
• HIGHLY protein bound, caution with warfarin, NSAID drugs, and sulfonylureas
• The combination of the sulfa drug with the oral contraceptive may reduce the effectiveness of the contraceptive
• The combination with the oral antidiabetic drug may potentiate the hypoglycemic effect of the sulfonylurea drug
• The combination with the phenytoin may potentiate the toxic effects of the phenytoin

Nursing Considerations and Patient Education

• Take with 2000 to 3000 mL of fluid/24 hr
• May cause crystalluria- increase fluids!
• Assess red blood cell count before beginning therapy
• Take oral doses with food
• Remember: MONITOR for SULFA ALLERGY with use of BACTRIM

Beta Lactams

MOA

• Normal cell wall synthesis is disrupted.
• Result: Bacteria cells die from cell lysis.

Works Against

• Gram + bacteria.

Commonly Used For Conditions Including

• (Not specified in the provided text)

Common Drugs to Know

Penicillins (various types)

• Natural penicillins
  • penicillin G
  • penicillin V
• Penicillinase-resistant drugs
  • Oxacillin
• Aminopenicillins
  • amoxicillin
  • ampicillin
• Extended-spectrum drugs
  • piperacillin
• Amoxicillin/Clavulanic acid (Augmentin) Penicillin antibiotic

Common Adverse Effects

• Nausea, vomiting, diarrhea, abdominal pain

CAUTION

• MANY interactions!
  • Nonsteroidal anti-inflammatory drugs
  • Oral contraceptives
  • Warfarin
  • Others – cehpalosporins!!

Nursing Considerations and Patient Education

• Take oral doses with water (not juices) because acidic fluids may nullify the drug’s antibacterial action
• Monitor patients taking penicillin for an allergic reaction for at least 30 minutes after administration
  • Wheezing, pruritis, urticaria
• If experiencing s/s of allergic reaction, STOP the medication; if anaphylactic and becomes unresponsive, give epinephrine

Cephalosporins (Ceph/Cef)

MOA

• Inhibits peptidoglycan, interfering with bacterial wall synthesis Result - Bactericidal action; Broad spectrum

Works Against

• Various bacterial strains depending upon generation (First – Fifth Generations)

Common Drugs to Know

First Generation

• Good gram-positive coverage, Poor gram-negative coverage
• Common uses: surgical prophylaxis and for susceptible staphylococcal infections
• Examples: cephalexin (Keflex); cefazolin (Ancef)

Second Generation

• Good gram-positive coverage, better gram-negative coverage than first generation
• Common uses: surgical prophylaxis (abdominal or colorectal surgeries)
• Examples: cefoxitin (Mefoxin), cefuroxime (Zinacef)

Third Generation

• Most potent group against gram-negative bacteria, Less active against gram-positive bacteria
• Common uses: bacterial bronchitis/pneumonia, meningitis, gonorrhea
• Examples: cefdinir (Omnicef), ceftriaxone (Rocephin)

Common Adverse Effects (Similar to Penicillins)

• Mild diarrhea, abdominal cramps, rash, pruritus, redness, edema

CAUTION

• Potential cross-sensitivity with penicillins if allergies exist

Nursing Considerations and Patient Education

• Assess for penicillin allergy; may have cross-allergy
• Give orally administered forms with food to decrease GI upset even though this will delay absorption
• Some of these drugs may cause a disulfiram (Antabuse)-like reaction when taken with alcohol – AVOID TAKING WITH ALCOHOL
• ASSESS FOR PENICILLIN ALLERGY!!!

Macrolides

MOA

• Prevent protein synthesis within bacterial cells
• Considered bacteriostatic
• Bacteria will eventually die
• In high enough concentrations, may also be bactericidal

Commonly Used For Conditions Including

• Strep infections- Streptococcus pyogenes (group A beta-hemolytic streptococci)
• Mild to moderate upper and lower respiratory tract infections- Haemophilus influenzae
• Spirochetal infections- Syphilis and Lyme disease
• Gonorrhea, Chlamydia, Mycoplasma

Common Drugs To Know

• erythromycin (E-mycin)
• azithromycin (Zithromax) – monitor for palpitations/chest pain
• clarithromycin (Biaxin)
• fidaxomicin (Dificid, Dificlir) – for CDIFF
• clindamycin

Common Adverse Effects

• Ototoxicity- tinnitus, dizziness and vertigo
• GI effects (primarily with erythromycin)
  • Nausea, vomiting, diarrhea, hepatotoxicity, flatulence, jaundice, anorexia
• Azithromycin and clarithromycin: fewer GI adverse effects, longer duration of action, better efficacy, better tissue penetration; clindamycin – high risk of Cdiff – (watery diarrhea, cramps, fever – collect stool specimen!)

Nursing Considerations and Patient Education

• Monitor and report for manifestations of ototoxicity such as tinnitus, dizziness and vertigo
• These drugs are highly protein bound and will cause severe interactions with other protein-bound drugs
• Absorption of oral erythromycin is enhanced when taken on an empty stomach, but because of the high incidence of GI upset, many drugs are taken after a meal or snack
• MONITOR FOR OTOTOXICITY!!!

Tetracyclines (-cycline)

MOA

• Inhibit bacterial protein synthesis by binding to 30s bacterial ribosome​
• Bacteriostatic: inhibit bacterial growth
• Inhibit protein synthesis
• Stop many essential functions of the bacteria

Works Against

• Wide spectrum
  • Gram-negative and gram-positive organisms, protozoa, Mycoplasma spp., Rickettsia spp., Chlamydia, syphilis, Lyme disease, acne, others

Common Drugs To Know

• tetracycline
• doxycycline (Doryx, Vibramycin)
• minocycline (Minocin)

CAUTION

• Strong affinity for calcium
  • Discoloration of permanent teeth and tooth enamel in fetuses and children or nursing infants if taken by the mother
  • Do not take in pregnancy - May retard fetal skeletal development

Nursing Considerations and Patient Education

• Do not drink milk within two hours (either before or after) of taking tetracycline
  • Dairy products, antacids, and iron salts reduce oral absorption of tetracyclines; Avoid because of the chelation and drug- binding that occur
• Both food and milk can reduce the amount of medicine absorbed by your body, making it less effective in fighting infection
• Avoid milk products, iron preparations, antacids, and other dairy products
• Do not use in children younger than age 8 years or in pregnant or lactating women because tooth discoloration will occur if the drug binds to the calcium in the teeth
• Avoid sunlight and tanning beds due to photosensitivity
• Take all medications with 6 to 8 oz of fluid, preferably water
• CAUTION because of CALCIUM

Aminoglycosides

MOA

• Bactericidal; prevent protein synthesis

Works Against

• Kills mostly gram-negative bacteria; some gram-positive also
• Used to kill gram-negative bacteria such as Pseudomonas spp., E. coli, Proteus spp., Klebsiella spp., Serratia spp.
• Often used in combination with other antibiotics for synergistic effects
• Used for certain gram-positive infections that are resistant to other antibiotics
• Poor oral absorption; no PO forms (typically given IV or IM)

Common Drugs To Know

• gentamicin (Garamycin)
• neomycin (Neo-fradin)
• tobramycin (Nebcin)
• amikacin (Amikin)
• kanamycin
• streptomycin

Common Adverse Effects

• Headache
• Paresthesia
• Fever
• Superinfections
• Vertigo
• Skin rash
• Dizziness

CAUTION

• Can cause serious toxicities
  • Nephrotoxicity
  • Ototoxicity

Nursing Considerations and Patient Education

• Must monitor drug levels to prevent toxicities
• Must monitor trough levels and serum creatinine
• Increase fluid intake of 2-3L a day
• Gentamicin: Peak: 4-10 mcg/mL Trough: 1-2 mcg/mL
• Monitor: *Nephrotoxicity *Ototoxicity *serum levels *When applied topically, wash and dry area first

Quinolones/floroquinolone (-floxacin)

MOA

• Bactericidal
• Alter DNA of bacteria, causing death (Do not affect human DNA)

Works Against

• Gram-negative bacteria such as pseudomonas

Commonly Used For Conditions Including

• Respiratory infections
• Bone and joint infections
• GI infections
• Skin infections
• Sexually transmitted diseases
• Anthrax

Common Drugs To Know

• ciprofloxacin (Cipro)
• norfloxacin (Noroxin)
• levofloxacin (Levaquin)
• moxifloxacin (Avelox)

Adverse Effects

• Monitor for CNS effects, GI discomfort, prolonged QT interval, superinfection

Black box warning

• increased risk of tendonitis and tendon rupture

Other Antibiotics to Know

vancomycin (Vancocin) class of glycopeptide antibiotics

MOA

• Natural, bactericidal antibiotic; Destroys cell wall

Commonly Used For

• Treatment of choice for MRSA and other gram-positive infections

Adverse Effects

• May cause ototoxicity and nephrotoxicity

Nursing Considerations

• Must monitor blood levels (and trough levels) to ensure therapeutic levels and prevent toxicity
• Should be infused over 60 minutes; monitor IV site closely
• MONITOR IV INFUSION RATE
• Rapid infusions may cause hypotension
• Ensure adequate hydration (2 L fluids/24 hr) if not contraindicated to prevent nephrotoxicity

CAUTION

• Red man syndrome may occur
  • Flushing/itching of head, neck, face, upper trunk
  • Tachycardia
• Decrease/slow infusion rate if you notice these symptoms
• May cause anaphylaxis if infusion not slowed down

Priority

• Monitor respiratory status and report any audible inspiratory stridor
• MRSA

Anti-Viral Drugs (-vir)

ribavirin

• Viral nucleoside inhibitor
  • Can treat severe lung infections caused by RSV when inhaled
  • Can be used to treat Hepatitis C

Acyclovir/Valcyclovir

• Herpesvirus Nucleoside Analog DNA Polymerase Inhibitor
  • Can treat herpes infections of skin, mouth, mucous membranes, anorectal viral infection
  • Herpes zoster (shingles), chicken pox, genital herpes
  • DOES NOT CURE, can alleviate pain and clear infection faster

ganciclovir

• Cuanosine analog antiviral
  • Can treat/prevent cytomegalovirus/ (CMV) in oral form
  • Can treat viral eye infections

oseltamivir (Tamiflu)

• Neuraminidase inhibitor
  • Can be used for influenza if taken within 48 hours of symptoms onset
  • DOES NOT CURE, can reduce duration of symptoms

Zanamivir

• Antiviral to treat infection cause by influenza A and B virus; take within 48 hours of symptom onset

Anti-retroviral therapy HAART

Highly active antiretroviral therapy HAART

• Includes at least three medications “Cocktails”
• These medications work in different ways to reduce the viral load of HIV1-RNA & increase in CD4 cells

HIV Medications

• protease inhibitors, reverse transcriptase inhibitors, integrase inhibitors, Nucleoside reverse transcriptase inhibitors, fusion inhibitors

zidovudine (Retrovir)

• First anti-HIV medication
• Nucleoside reverse transcriptase inhibitor
• Can be given to pregnant HIV-positive women and newborn babies to prevent maternal transmission of HIV
• Major dose-limiting adverse effect: bone marrow suppression (lowers RBC, WBC, platelets)

Anti-Fungal Drugs

• Can be systemic or topical
• Broken down into major groups based on their chemical structure:

Polyenes: amphotericin B and nystatin

• Bind to sterols in cell membrane lining
  • Result: fungal cell death
  • Do not bind to human cell membranes or kill human cells
• Amphotericin B is drug of choice for severe, systemic fungal infections
• Nystatin may be used for oral thrush/oral candidiasis; swish 2 minutes and swallow the medication

Imidazoles: ketoconazole AND Triazoles: fluconazole, itraconazole, voriconazole

• Inhibit fungal cell cytochrome P-450 enzymes, resulting in cell membrane leaking
  • Lead to altered cell membrane
  • Result: altered cellular metabolism and fungal cell death
• Fluconazole tablet may be used for vaginal yeast infection

Echinocandins: caspofungin, micafungin

• Prevent the synthesis of glucans, which are essential components of fungal cell walls
  • Causes fungal cell death
• May be used for serious fungal infections of blood, esophagus, lungs

Allylamines : Terbinafine- onychomycosis

Amphotericin B

• Drug of choice for severe, systemic fungal infections

Adverse Effects (many body systems)

• Pulmonary infiltrates
• Fever/Chills
• Cardiac dysrhythmias
• Nausea and GI upset
• Renal toxicity
• Neurotoxicity
• Nephrotoxicity
• Headache, malaise
• Tingling, numbness in hands and feet (parasthesia of extremities)

Monitor

• Renal Toxicity BUN *Hold medication if BUN>40mg/L Neurotoxicity Monitor for cardiac dysrhythmias

Nursing Consideration and Patient Education

• Many antifungal drugs are metabolized by the cytochrome P-450 enzyme system
• Coadministration of two drugs that are metabolized by this system may result in competition for these enzymes, and thus higher levels of one of the drugs
• Before beginning therapy, assess for hypersensitivity, possible contraindications, and conditions that require cautious use
• Obtain baseline VS, CBC, liver and renal function studies, and ECG
• Assess for other medications used (prescribed and over-the-counter) so as to avoid drug interactions
• Low urine output (oliguria)
• Lowered potassium and magnesium levels

NSAIDS

Properties all NSAIDs share

• Antipyretic
• Analgesic
• Antiinflammatory

Contraindications

• Patients with documented aspirin allergy must not receive NSAIDs

Conditions that place the patient at risk for bleeding

• Vitamin K deficiency
• Peptic ulcer disease

Adverse Effects

• GI: heartburn to severe GI bleeding
• Acute renal failure
• Noncardiogenic pulmonary edema
• Increased risk of MI and stroke
• Altered hemostasis
• Hepatotoxicity
• Skin eruption, sensitivity reaction
• Tinnitus, hearing loss
• AVOID ALCOHOL; NSAIDs taken with alcohol may result in increased risk of GI bleeding

Monitor with NSAIDS

• Renal function
• May cause renal toxicity

Black Box warning

• All NSAIDs (except aspirin) Increased risk of adverse cardiovascular thrombotic events, including fatal MI and stroke

Nursing Implications

• Contraindications to therapy
  • GI lesions or peptic ulcer disease and bleeding disorders

Remember

• Do not give if history of gastric ulcers/GI bleeding
• Avoid use with alcohol
• Monitor renal function
• Do not give salicylates to children and teenagers because of the risk of Reye’s syndrome
• Better tolerated if taken with food, milk, or an antacid to avoid irritation
• Therapeutic effects may not be seen for 3 to 4 weeks
• Monitor for unusual bleeding (bleeding in the stool)

Aspirin

Low dose

• for thromboprevention Shown to reduce cardiac death after myocardial infarction (MI)

Nursing Implications

• Do not give salicylates to children and teenagers because of the risk of Reye’s syndrome

Monitor for Salicylate Toxicity

• Cardiovascular: increased heart rate
• Central nervous: tinnitus, hearing loss, dimness of vision, headache, dizziness, mental confusion, lassitude, drowsiness
• GI: nausea, vomiting, diarrhea
• Metabolic: sweating, thirst, hyperventilation, hypoglycemia, or hyperglycemia

Gout

Condition that results from inappropriate uric acid metabolism

• Underexcretion of uric acid
• Overproduction of uric acid
• Uric acid crystals are deposited in tissues and joints, resulting in pain
• Hyperuricemia (elevated uric acid)

Commonly Used Medications

Allopurinol (Zyloprim)

• Prevents or lowers high uric acid levels in the blood
• Used to prevent uric acid production and to prevent acute tumor lysis syndrome
• Exfoliative dermatitis, Stevens-Johnson syndrome, and toxic epidermal necrolysis
• INCREASE FLUID INTAKE 2-3L/DAY

Colchicine

• Reduces inflammatory response to the deposits of urate crystals in joint tissue
• Used for short-term management or prevention of gout
• May cause short-term leukopenia (low WBC count) and bleeding into the GI or Monitor for muscle pain (rhabdomylosis)
• Monitor for GI symptoms of toxicity including diarrhea • If occurs, discuss discontinuing the medication with provider

MONITOR

• BLEEDING, PAIN (Rhabdomylosis), DIARRHEA

• takes weeks for therapeutic effect to be achieved, take daily

DIETARY CONSIDERATIONS FOR GOUT

• Avoid alcohol and foods high in purine (red meats, organ meats, fatty poultry, high fat dairy, high sugar foods).