Pharm - Anti-infectives

• Rifampin

  indication: used for TB (anti-tubercular medication)

  side effects: orange discoloration of tears, sweat, urine
• First line medication for tuberculosis

  isoniazid (INH)

  ** dietary supplementation w/ pyridoxine (Vit B6) this drug leads to deficiency
• superinfection- signs & sx

  - fever

  - perineal itching

  - cough

  - lethargy

  - unusual discharge
• Tx for mild cough

  antitussives: drugs used to stop or reduce coughing

  - opioid, non-opioid & combined

  - only for non productive cough

  - nonopioid: dextromethorphan (vicks, robitussin) benzonatate

  - opioid: codeine
• Contraindications for real PCN allergy pts

  pts that are allergic to penicillin have a higher risk of allergy to beta-lactam antibiotics

  
  

  pts w/ hx of throat swelling or hives form penicillin should NOT take CEPHALOSPORINS

  • potential cross-sensitivity is real allergy exists
  • 1-4 % of pts will have slight allergic reaction
• Antibiotics for UTI that can cause crystalluria and affect bone marrow

  - sulfonamides

  adverse effects:

  - hemolytic & aplastic anemia

  - thrombocytopenia

  - hepatoxicity

  - crystalluria
• HIV drugs

  Nucleoside / nonnucleoside Reverse transcriptase inhibitors (NRTIs / NNRTI)

  • block activity of the enzyme reverse transcriptase, preventing production of new viral DNA
  • adverse effect: mitochondrial toxicity

  protease inhibitors, fusion inhibitors, entry inhibitor-CCR5 coreceptor antagonists, HIV integrate strand transfer inhibitors (INSTI)
• Vancomycin

  indication: tx of choice for MRSA & other gram-positive infections

  - narrow therapeutic index (10-20)

  - rapid infusion may cause hypotension / red man syndrome

  - red man syndrome: flushing / itching of head, neck, face, upper trunk

  - antihistamine may be ordered to reduce these effects
• Aminoglycoside: SE

  causes serious toxicity: nephrotoxicity, ototoxicity

  - must monitor drug levels to prevent toxicities (peak & trough)

  - minimum inhibitory concentration (MIC) - lowest therapeutic lvl
• Tamiflu

  anti-viral drug

  - active against influenza types A & B
• Herper zoster meds

  Acyclovir (zovirax)

  MOA: nucleoside analog

  - decreases outbreaks of HSV1 and HSV2 but doesn't cure it

  Indicated for:

  - HSV1, HSV2, zoster varicella
• Fluoroquinolones

  side effects

  - cardiac: prolonged QT interval

  - BLACK BOX warning: rupture tendons, tendonitis
• Tetracyclines: SE

  - should not be used in children under 8 or in pregnant / lactating women because tooth discoloration will occur if the drug binds to the calcium in the teeth

  - avoid milk products & sunlight / UV (photosensitivity)

  - avoid dairy, antacids & iron salts it reduces oral absorption of tetracyclines
• General teaching about antibiotics

  - instruct patient to take antibiotics exactly as prescribed & length of tx

  - should not stop taking even if they start feeling better before med are done
• Indications for antibiotics (empiric vs definitive vs prophylactic)


  - empiric: treatment of an infection before specific culture info has been reported or obtained

  - definitive: antibiotic therapy tailored to treat organism identified with cultures

  - prophylactic: treatment w/ antibiotics to prevent an infection, as in intra-abdominal surgery or after trauma (preventative)
• PrEP vs PEP

  PrEP: pre-exposure prophylaxis

  - for pts having contact w/ HIV, multiple sex partners, needle drug use -high risk activity

  PEP: post-exposure prophylaxis

  - up to 72 hrs after exposure

  - diminish HIV rep
• Combination agents to treat HIV

  - combination agents: NRTI/NNRTI + other drugs

  - biktarvy: INSTI + NRTI x2

  - bictegravir / emtricitabine / tenofovir alfenamide

  - dovato: INSTI, NRTI

  - dolutegravir / lamivudine
• Colony stimulating agents

  Factors: signal bone marrow (hematopoietic cells) to increase WBC count

  - filgrastim
• Erythropoiesis stimulating agents

  purpose: stimulate RBC growth / production

  - epoetin alfa
• Fungal infection due to antibiotic

  Fluconazole (diflucan)

  - effective: candida albicans but narrow spectrum

  - pts w/ AIDS, bone marrow transplants, chemo

  Nystatin (mycostatin)

  - effective: candida infections (oral candidiasis)
• culture before treating w/ antibiotics

  - empiric tx is given until culture results are back (48-72 hrs)
• possible problems w/ use of antibiotics

  - superinfection

  - pseudomembranous colitis

  - secondary infection

  - resistance

  - food-drug interactions

  - host factors

  - allergic reactions
• Antibiotic vs Antiviral

  Antibiotic: used to treat bacterial infections

  Antiviral: used to kill or suppress the virus or inhibit the ability for the viruses to replicate