Drug Therapy with Antibiotics

Cephalosporins

• Broad spectrum

• Divided into groups (generations) according to their antimicrobial activity

• Structurally and pharmacologically related
  to penicillin’s

  • Avoid if pt is allergic to PCN

Cephalosporins Generations

• As the 1st, 2nd and 3rd generations progress they an increase in the sensitivity of gram-negative microorganisms and a decrease in the sensitivity of gram-positive microorganisms

• The 4th and 5th generations show activity towards both.

• Resistance to beta lactamase increases .

cefazolin & cephalexin (Keflex)

• First Generation Cephalosporins 

• Used for Surgical prophylaxis

  • esp. for prosthetic implants r/t staph infection potential

cefaclor (Ceclor) & cefuroxime (Zinacef)

• Second Generation Cephalosporins 

• Used prophylactically for  gynecologic or colorectal surgeries

cefdinir (Omnicef) & ceftriaxone (Rocephin)

• Third Generation Cephalosporins 

• Broad Spectrum

• Uses:

  • When pt is resistant to other abx

  • E. Coli

  • Meningeal infections

Cefepime (Maxipime)

• Fourth Generation Cephalosporin

• Broader spectrum of antibacterial activity than third generation

• Uses:

  • Strep and staph

  • you may see this occasionally for UTIs 

Ceftaroline (Teflaro)

• Fifth Generation Cephalosporin

• Broader spectrum of antibacterial activity

  • Effective against a wide variety of organisms

• Uses:

  • Community acquired pneumonia 

  • Skin infections (cellulitis)

  • Can be used for MRSA

    • Vancomycin is more commonly used for MRSA

Cephalosporins Adverse Effects 

• Abdominal cramps

• N/V/D 

• Potential cross-sensitivity with penicillin's

Drugs that decrease the effects of Cephalosporins

• Furosemide

• Other abx

• alcohol

Cephalosporins Contraindications

• If previous anaphylactic reaction to PCN (Penicillan)

• Cephalosporin allergy

What should you do if patient says that they had an allergic reaction to a medication?

• you need to ask what happened when patient states that they have an allergy 

  • patient may just be experiencing side effects of medication rather than allergic reaction

Cephalosporins Nursing Implications

• Assess for penicillin allergy; may have cross allergy

• Administer with food to decrease GI upset, even though this will delay absorption

• Instruct pt to take full course of meds! Even if feeling better

Imipenem-cilastatin (Primaxin) & Meropenem

• Carbapenems

• Broad Spectrum

• Uses:

  • Resp tract infection, UTI, abd infections, skin/bone infections

Aminoglycosides

• Broad Spectrum

• Poor oral absorption

  • No PO forms (exception neomycin)

• Limited use

  • Related to how potent it is

  • Can cause serious toxicity

  • Needs serum drug levels

  • If we dont need them we don’t use them 

Aminoglycosides Examples

• gentamicin 

• neomycin (Neo-fradin)

• tobramycin (TOBI)

Aminoglycosides Indications for Use

• resp infections

• UTI

• abd infections

• osteomyelitis (bone inflammation)

• pseudomonas

• sepsis

• Often used in combination with other antibiotics for synergistic effects

• Used for certain infections that are resistant to other antibiotics

Gentamicin Routes

• IM, IV and ophthalmic (absorbs poorly via GI tract)

Neomycin Routes

• Given orally → decontaminates GI tract before surgical procedures

• Given topically for eye/skin/ear infections

• Given as enema for bowel cleansing  for surgery or some sort of procedure or constipation

• Can also be given Ophthalmically

Aminoglycosides Adverse Effects

• Toxicity

  • Gentamicin and Tobramycin need serum levels drawn during tx & must be monitored for therapeutic levels during tx.

  • Adjustments made with renal or hepatic impairment

• Ototoxicity

  • HA

  • Vertigo

  • Dizziness

  • Ringing in ears

  • Some patients may even complain about hearing loss

• Numbness

• skin tingling

• muscle twitching

Aminoglycosides Black Box Warning 

• Nephrotoxic & Ototoxic

ciprofloxacin (Cipro) & levofloxacin (Levaquin)

• Fluoroquinolones

• Broad spectrum

• Uses:

  • respiratory

  • bone

  • joint

  • skin

  • soft tissues

  • GI

  • GU

  • STIs

ciprofloxacin (Cipro) & levofloxacin (Levaquin) Nursing Implications

• These are usually given PO because they have excellent oral absorption

• If given IV it must be over 1 hour

  • Irritates the vein

  • if vein is inflamed then we may need to change IV site 

ciprofloxacin (Cipro) & levofloxacin (Levaquin) Adverse Effects

• Headache

• dizziness

• N/V

• Abd discomfort 

• Risk of aortic aneurysm

• Photosensitivity

  • Stay out of sunlight

ciprofloxacin (Cipro) & levofloxacin (Levaquin) Black Box Warning

• Increased risk of tendonitis and tendon rupture

• Increase risk of peripheral neuropathy & CNS effects
  

• QT Prolongation – risk for dysrhythmia

Tetracycline & Doxycycline (Vibramycin)

• Tetracyclines 

• Broad Spectrum 

• Uses:

  • Chlamydia

  • syphilis

  • Lyme disease

  • animal bites

  • acne

  • chronic bronchitis

  • H-pylori tx

Tetracycline & Doxycycline (Vibramycin) Nursing Implications

• Must take around the clock as it inhibits but does not kill bacteria

• Take with 8oz of water

• Give 1 hour before or 2 hours after Dairy products, antacids, & iron supplements

• Tetracyclines will decrease the effect of birth control

Tetracycline & Doxycycline (Vibramycin) Contraindications 

• Pregnancy & Breastfeeding

• Children under age 8

  • Tooth discoloration (for children and/or fetus) will occur if drug binds to calcium in teeth

  • May interfere with bone growth

• renal failure and caution with hepatic failure 

Tetracycline & Doxycycline (Vibramycin) Adverse Effects

• anaphylaxis

• Rash

• urticaria

• serum sickness

• Flatulence

• N/V/D

• pseudomembranous colitis 

• Intracranial hypertension

• Photosensitivity

• Candida (sore throat, furry or black tongue)

Sulfonamides 

• Sulfonamides

  • One of the first groups of antibiotics

  • Often combined with another antibiotic

    • Sulfamethoxazole combined with trimethoprim known as Bactrim

Sulfamethoxazole/trimethoprim (Bactrim)

• Sulfonamides 

• Broad Spectrum

• Take with full glass of water

Sulfamethoxazole/trimethoprim (Bactrim) Uses

• UTIs

• Upper respiratory tract infections

• Outpatient Staphylococcus infections

  • Vancomycin is usually the drug given for MRSA

Sulfamethoxazole/trimethoprim (Bactrim) Drug Interactions

• Oral Contraceptive = decreases effectiveness

• Diabetic Meds = potentiates hypoglycemia

• Phenytoin = potentiates toxicity 

Sulfamethoxazole/trimethoprim (Bactrim) Adverse Effects 

• Abdominal pain

• N/V/D

• anorexia

• pancreatitis

  • amylase & lipase labs are monitored for pancreatitis 

• Pruritus

• urticaria

• SJS

• skin photosensitivity

• Increased BUN and serum creatinine

• renal failure

• interstitial (a kidney disorder in which the spaces between the kidney tubules become swollen (inflamed))

• Agranulocytosis = decrease in WBC

• Aplastic anemia = bone marrow fails to produce all three major types of blood cells

• WBC issues

Nitrofurantoin (Macrodantin)

• Adjuvant Drug for UTI

• Used for recurrent UTIs

• Take with food

Nitrofurantoin (Macrodantin) Contraindications

• Pregnancy

• Older adults r/t risk of toxicities

Nitrofurantoin (Macrodantin) Adverse Effects

• N/V/D most common

• Cardiac & CNS changes

Macrolides Examples

• Erythromycin - prototype 

• Azithromycin (Zithromax) aka Z-pack 

• clarithromycin

Macrolides Administration

• Take on empty stomach if PO (1 hr before of 2 hrs after meal)

• Do not take within 2 hours of dairy and antacids 

• Do not take with grapefruit juice or oranges (many types)

  • citrus can cause cardiac problems 

• Take with 8 oz water

• Take around the clock

Erythromycin

• Macrolide

• a PCN substitute in patients who are allergic to PCN

Azithromycin (Zithromax)

• Macrolide

• Used for ENT and sinus infections

Clarithromycin

• Macrolide

• used in combination with Omeprazole (Prilosec) to treat H Pylori

Macrolides Indications for use

• Strep & staph infections
  

• Certain URI’s (upper respiratory tract infections)

• Gonorrhea, chlamydia
  

• C-diff tx
  

• Prophylactic for procedures, prior to sx, or dental procedures 

Macrolides Adverse Effects

• N/V/D

• anorexia

• Pseudomembranous colitis

• Fever

• Confusion

• ototoxicity (Irreversible hearing loss)

• Jaundice

• Hepatotoxicity

• Cardiac dysrhythmias with IV administration

• Increase in Dig levels

  • Dig Toxicity

Clindamycin (Cleocin)

• This can be given as a vaginal suppository & topical

• Uses

  • strep/staph/pneumococcal infections

  • Topical for acne

  • vaginosis

Clindamycin (Cleocin) Administration

• Take with full glass of water

• Dilute if giving IV to avoid phlebitis

• Risk for cardiac even if given as bolus

Clindamycin (Cleocin) Black Box Warning

• Possible fatal colitis

• If diarrhea develops: discontinue and check for C-diff

  • we need to put pt in isolation until confirmed negative 

Linezolid (Zyvox) Uses

• Uses:

  • VRE

  • HAI’s

  • skin infections,

    • including those with MRSA, staph, strep

Linezolid (Zyvox) Adverse Effects

• Bone marrow depression (monitor CBC)

  • anemia,

  • leukopenia,

  • thrombocytopenia,

  • pancytopenia (everything is low)

Linezolid (Zyvox) Interactions & precautions

• Avoid foods containing tyramine while on this medication

  • aged cheese, beer, red wine, liver, aged meat, sauerkraut, 

• Do not infuse with any other med

• Flush line completely before starting another drug

Linezolid (Zyvox) Black Box Warning

• DO NOT take with SSRI’s, SNRI’s , TCA’s or MAOI’s

• It can cause serotonin syndrome 

  • pt could have shivering, diarrhea, muscle rigidity, fever, & death 

Metronidazole (Flagyl)

• Uses:

  • Prophylactic tx in colorectal sx

  • Intra-abd infections

  • Tx of C-diff

  • Combo tx for H. pylori

Metronidazole (Flagyl) Adverse Effects

• skin rash

• pruritus

• thrombophlebitis at the infusion site.

• seizures

• ataxia

• headache

• confusion

• dizziness

• N/V/D

• metallic taste

Metronidazole (Flagyl) Contraindications

• With CNS or blood disorders

• Alcohol

Vancomycin

• Best tx of MRSA

  • Also used for C-diff and colitis

Vancomycin Nursing Implications

• Serum levels needed

  • we have to get peak & trough levels 

  • we draw the trough immediately before we give the next dose 

  • we draw the peak depending on the dose, frequency & the route

  • If the trough is elevated we have risk for ototoxicity & renal toxicity 

• we may also look at urine output for toxicity 

• Infuse slowly (over an hour)

• Reduce the dosage in the presence of renal impairment

Vancomycin Adverse Effects

• Red Man Syndrome 

  • Flushing/itching of head, neck, face, upper trunk

  • Antihistamine may be ordered to reduce these effects

• Rapid Infusions May cause hypotension

  • Dilute and infuse over 1 hour

  • symptoms may be alleviated or decreased if we slow the infusion

Vancomycin Contraindications

• Not for pregnant or nursing moms