Anti-Infective Agents UAB NUR 328

Bactericidal Meds

directly lethal to the microbe

Bacteriostatic Meds

slows the rate of growth of the microbe and leaves it to the immune system to destroy the organism

Narrow Spectrum

you know what organism you are treating (culture data), and can target therapy to that specific microbe

Broad Spectrum

general idea of what organisms you likely need to treat, and can start with medications that many different infections will be susceptible to (empiric therapy)

Gram Positive

commonly associated with infections of the respiratory tract and soft tissues (staphylcocci, streptococci, enterococci)

Gram Negative

commonly associated with infections of the genitourinary tract or GI tract (bacteroides, E. coli, klebsiella, proteus, pseudomonas, salmonelle, shigella)

Therapeutic Index

difference between the blood concentration of the drug that is toxic and the blood concentration of the drug that is therapeutic (draw labs, drugs affect other drug levels)

Trough

blood specimen collected immediately before med given

Peak

blood specimen collected 30 minutes after infusion finishes

Medication Administration Common Adverse Effects

• Anytime a drug is administered IV - watch for development of phlebitis

• Anytime a drug is administered IM - watch for pain/redness at site of injection

• Anytime a drug is administered PO - watch for GI upset

• Anytime you give a new antibiotic, watch for a reaction, and be mindful of cross-reactions from other allergies.

Infections

occur when microorganisms invade a host, attach to host cell receptors, and multiply in sufficient numbers to cause injury

Microorganisms

infection producing microscopic organisms; bacteria, fungi, virus, and/or parasites

Nosocomial Infections

occur in hospital or hospital like settings

Community Acquired Infections

infections that originate in a community setting

Opportunistic Pathogens

microorganisms that cause disease only when a person’s immune system is weakened or when they enter parts of the body they don’t normally belong

Immunosuppressed

preference for bactericidal meds, rather than bacteriostatic b/c pt’s immune system can’t provide the “help” that bacteriostatic meds need

Antibiotic Resistance - Behaviors

• Aseptic technique for all procedures

• Culture specimens (get cultures before giving a dose of antibiotics)

• Timely communication of culture and sensitivity reports

  • Narrow spectrum vs Broad spectrum

  • Combination therapy

• Teach client to complete ENTIRE supply of antibiotics/duration of therapy

Culture and Sensitivity Testing

When a C & S is ordered, it generally takes 72 hours for a final report

Sensitivity

Determination of which meds the bacterium is most sensitive to

Meds w/ SE of Photosensitivity

• Ciprofloxacin

• Trimethoprim-Sulfamethoxazole

• Tetracycline

Meds w/ SE of SJS

• Trimethoprim-Sulfamethoxazole

• Erythromycin

Meds w/ SE of Bone Marrow Depression

• Ciprofloxacin

• Trimethoprim-Sulfamethoxazole

• Tetracycline

• Clindamycin

• Amphotericin B

Aminoglycosides Prototype

Gentamicin

Gentamicin Uses

Bactericidal -> gram negative aerobic infections

Gentamicin MOA

disrupts protein synthesis

Gentamicin AE

• Nephrotoxicity (may be reversible)

• Ototoxicity (may be permanent)

  • Hearing loss and loss of balance

• GI: n/v, diarrhea, liver function

• Allergic reactions

• Musculoskeletal

  • Muscle twitching or weakness

• Equilibrium loss

  • Loss of coordination

Gentamicin CI/C

• Pregnancy (Cat D)

• Renal insufficiency

• Older adults (higher toxicity risk)

• Neuromuscular blockers/diuretics - caution w/ interactions

• Ear issues (pre-existing hearing loss)

Gentamicin DI

• Other ototoxic or nephrotoxic meds

  • Aspirin, macrolides, loop diuretics, NSAIDs

• any neuromuscular blocking drugs

Gentamicin NI

• make sure pt is well hydrated

• Monitor peak and trough blood levels.

• Monitor laboratory values

  • BUN, creatinine, urine for protein and casts

Carbapenems Prototype

imipenem + cilastatin

Imipenem + Cilastatin Uses

Broad-spectrum beta-lactam effective against gram (+) and gram (–) bacteria

Imipenem + Cilastatin MOA

• Bactericidal

  • destroys bacterial cell wall

Imipenem + Cilastatin CI/C

• Caution with inflammatory bowel disease

• Allergy

  • possible cross-sensitivity to penicillin or cephalosporins

• Pregnancy/lactation

  • safety not established

• Sz disorders/drugs prescribed for seizures

  • reduces their effectiveness and can lead to breakthrough seizures

Imipenem + Cilastatin AE

• Renal toxicity

• Altered mental state (CNS effects: HA, dizziness)

• GI: diarrhea/bloody/mucus -> c. diff/ pseudomembranous colitis, N/V

• Superinfection (colitis, black furry tongue, vaginal yeast infection)

Imipenem + Cilastatin NI

• Make sure pt is well hydrated

• Monitor renal function labs

Cephalosporins Prototype

• 2nd Generation:

  • Cefaclor

• 1st Generation:

  • Cephalexin

Cefaclor/ Cephalexin Uses

Action against gram positive and gram negative bacteria depending upon drug (broad-spectrum)

Cefaclor/ Cephalexin MOA

• Bactericidal

  • destroys bacterial cell wall

Cefaclor/ Cephalexin CI/C

• GI disease

• Allergy (to cephalosporin/penicillin)

  • Acceptable for use with pts who have MILD penicillin allergy

• Renal failure

• Pregnancy/lactation - risk vs reward

Cefaclor/ Cephalexin AE

• GI upset (diarrhea, N/V, abd pn, anorexia, c.diff (possible pseudomembranous colitis))

• Altered mental state (CNS: HA, dizziness, paresthesia)

• Superinfection

• Nephrotoxicity

• Disulfiram-like reaction (w/ alcohol)

Cefaclor/ Cephalexin DI

• pt. on oral anticoagulants may experience increase in bleeding

  • possible reduction in anticoagulant dose

• Alcohol -> pt. should avoid 72 hours post tx

  • causes disulfiram-like reaction

Cefaclor/ Cephalexin NI

• Make sure pt is well hydrated

• Take with food to minimize GI distress

• Avoid alcohol during tx and 72 hrs post tx

• Monitor hepatic / renal / coagulation labs

Fluroquinolones Prototype

Ciprofloxacin

Ciprofloxacin Uses

• Broad spectrum

• Bactericidal

Ciprofloxacin MOA

inhibition of enzyme necessary for DNA replication

Ciprofloxacin CI/C

• Children under 18

• Renal impairment

• Allergy

• Myasthenia gravis

• Pregnant/lactating

• Sz and GI disorders

Ciprofloxacin Black Box Warning

• Tendinitis

• Achilles tendon rupture

• peripheral neuropathy CNS effects

• exacerbation of muscle weakness in clients with myasthenia gravis

• Increased risk with administered corticosteroids

Ciprofloxacin AE

• CNS effects (H/A, insomnia)

• GI effects (c. diff, n/v)

• Neuropathy (peripheral)

• Achilles tendon rupture (Black Box)

• Tendonitis

• Superinfection/Photosensitivity

Ciprofloxacin DI

• cardiac drugs that increase QT interval

• theophylline (increases levels)

• coagulation modifiers (warfarin)

• GI drugs like antacids

• Dairy products decrease absorption

• Increased muscle weakness with corticosteroids

Ciprofloxacin NI

• Make sure client is well hydrated

• Avoid exposure to sunlight or sunlamp.

Penicillin and Penicillinase-Resistant Antibiotics Prototype

Amoxicillin, ampicillin, amoxicillin-clavulanate

Amoxicillin Uses

• Treats broad spectrum infections caused by gram (+) cocci and bacilli

• used to treat a variety of “coccal” infections

Amoxicillin MOA

Bactericidal; affect bacterial cell wall

Amoxicillin CI/C

• Pregnancy/lactation - risk vs reward

• Allergy

  • cross-sensitivity with cephalosporins and carbapenems

• Renal impairment - may need reduced dose

Amoxicillin AE

• GI upset (n/v, diarrhea)

• Allergic reactions

• Problem at IV site

• Superinfection (c. diff)

Amoxicillin DI

• Women use 2nd form of contraception during treatment -> can decrease birth control pill effectiveness

• Aminoglycosides

• When administered w/ some other antibiotics, there may be a decrease in effectiveness and an increase in SE

Amoxicillin NI

• Make sure client is well hydrated

• Take w/ meals to dec. GI effects

• Monitor hepatic / renal labs

Sulfonamides Prototype

trimethoprim-sulfamethoxazole

Trimethoprim-Sulfamethoxazole Uses

Bacteriostatic

Trimethoprim-Sulfamethoxazole MOA

blocks production of folic acid -> necessary for growth/ synthesis of new bacteria

Trimethoprim-Sulfamethoxazole CI/C

• Sulfonamide allergy (sulfa, sulfonylureas, thiazide diuretics)

• Immunosuppressed pts

• Caution w/ renal disease

• Kidney stones hx

• Pregnancy Cat X -> Teratogenic

Trimethoprim-Sulfamethoxazole AE

• GI: n/v, diarrhea, abdominal pain, anorexia, stomatitis

• Renal - nephrotic syndrome, crystalluria, hematuria, proteinuria

• Altered mental state (CNS: HA, dizziness, vertigo, depression)

• Bone marrow depression

• Steven-Johnsons syndrome

• Photosensitivity

• Jaundice/Hepatic injury

Trimethoprim-Sulfamethoxazole DI

• sulfonylurea drug - increased risk for hypoglycemia occurs

• Alcohol - disulfiram like reaction

• Reduced effectiveness of oral contraceptives

Trimethoprim-Sulfamethoxazole NI

• Renal labs and CBC

• Make sure client is well hydrated

• Take with food to minimize GI manifestations

• Increased incidence of CNS effects on geriatric pts

Stevens-Johnson Syndrome/ Toxic Epidermal Necrolysis (TEN)

• Rare, serious disorder of the skin and mucous membranes

• Reaction to a medication

• Begins with flu-like symptoms - followed by a painful red or purplish rash - then the affected skin dies and sheds

• Treated like a burn

Tetracyclines Prototype

Tetracycline

Tetracycline Uses

• Broad spectrum -> bacteriostatic

• Prescribed for a lot of skin conditions -> ACNE

Tetracycline MOA

inhibits bacterial protein synthesis

Tetracycline CI/C

• Children younger than 8 yrs old

• Pregnancy/lactation because of effect on teeth and bones

• Allergy

• Caution in pts with hepatic or renal dysfunction

• Kids (teeth discoloration)

Tetracycline AE

• Bone marrow depression

• Absorption is affected by food/iron/calcium

  • Can cause esophageal ulcerations

• Dental discoloration (yellow/brown)

• Superinfection

• Photosensitivity

• GI upset (n/v, diarrhea)

Tetracycline DI

• Increased levels of digoxin and warfarin

• Dairy products and supplements w/ iron or zinc

  • decrease absorption

• Decrease effectiveness of oral contraceptives

Tetracycline NI

• Take with non-dairy foods if GI manifestations occur.

• Report to provider if pregnant.

• Wear protective clothing and wear sunscreen for sun exposure.

Licosamides Prototype

Clindamycin

Clindamycin AE

• GI issues

• Bone marrow depression

• Skin infections

Clindamycin CI/C

• Hepatic or renal impairment

• Pregnancy/lactation

Macrolides Prototype

Erythromycin

Erythromycin Uses

• may be used for prophylaxis (pre-dental)

• Older antibiotics used to treat UTIs and URIs and are often used when clients allergic to penicillin

Erythromycin MOA

inhibits protein synthesis

Erythromycin CI/C

• Allergy

• Hypokalemia/Hypomagnesemia

• QT prolongation hx

• Liver/GI disorders (caution)

Erythromycin AE

• GI: cramping, vomiting, diarrhea, pseudomembranous colitis

• Liver toxicity

• Ototoxicity

• Superinfection

• Steven Johnson’s syndrome

• CV: abnormal heart rhythms (some life-threatening)

Erythromycin NI

Take on an empty stomach

Vancomycin Uses

• Bactericidal

• Staphylococcal infections, Gram + pathogens, C. diff

• May be used prophylaxis if the client allergic to penicillin

Vancomycin MOA

Binds to cell wall

Vancomycin CI/C

• Nephrotoxicity

• Ototoxicity

• Colitis

• Hypersensitivity/allergy

Vancomycin AE

• Hypersensitivity reactions (including anaphylaxis)

• Red Mans Syndrome (rapid infusion)

• Superinfection (black tongue, vaginal itching/discharge, loose stools)

Vancomycin DI

• Medications that are toxic to hearing or kidney

  • increase risk for ototoxicity or nephrotoxicity

Vancomycin NI

• Monitor vancomycin trough levels

• Monitor BUN and creatinine

Red Man Syndrome

• Symptoms are due to histamine release

• Not the same as SJS - resolves on its own

Anti-Mycobacterials (Anti-tuberculosis) Prototype

Isoniazid (INH)

Isoniazid Uses

• Given with rifampin, pyrazinamide, and ethambutol (multiple drug therapy like PUD)

• First-line drug

• Oral therapy for a minimum of 6 months

• Can be administered up to 2 yrs post neg sputum cultures in pts with HIV/AIDS

Isoniazid CI/C

• Hepatic failure

• Alcoholism

• Lactating/pregnancy - caution

• Failed renal or CNS function

Isoniazid AE

• Peripheral neuropathy

• Hepatotoxicity

• Anorexia

• Nausea

• Tinged (orange) fluids - Rifampin

• Overactive CNS (hallucinations)

• Mental changes

Isoniazid DI

• Severe reactions can occur with foods with high concentrations of tyramine

  • EX: aged cheeses, smoked and processed meats, fermented foods, pickled foods

Antivirals Prototype

Acyclovir

Acyclovir MOA

Works by inhibiting viral DNA replication

Acyclovir Uses

• Treatment of herpes 1 and 2 infections, HSV encephalitis; acute shingles and chickenpox

Acyclovir CI/C

• Dehydration

• Allergy

• Renal impairment

• Neurological disorders

Acyclovir AE

• Dizziness

• Rash

• Headache

• Insomnia

• Lightheadedness

• Tremors

Acyclovir NI

• Most effective when started quickly (within 24-48 hrs)

Anti-fungal Agents Prototypes

• Amphotericin B (systemic)

• Ketoconazole (superficial and systemic)