ANTIBIOTICS

Introduction

Top Test Tips for Antibiotics

Finish All Medications

• Complete the full prescribed course of antibiotics, even if symptoms improve, to prevent the risk of superinfections such as Clostridium difficile (C. Diff) and Methicillin-resistant Staphylococcus aureus (MRSA).

• Education is crucial: Patients should be informed that stopping antibiotics prematurely can lead to treatment failure and antibiotic resistance, making future infections harder to treat.

Accidental Pregnancy with Certain Antibiotics

• Classes affected: Penicillins and Tetracyclines (e.g., Penicillin, Doxycycline).

• Keywords: Oral contraceptives may become ineffective when used with these antibiotics. Women should consider additional contraception methods, such as an Intrauterine Device (IUD), during the antibiotic course to prevent unintended pregnancies.

• Remember the "Three C's": Child care need to be taken when prescribing penicillins and cyclins to women of childbearing age.

No Alcohol

• Alcohol consumption can exacerbate liver toxicity associated with many antibiotics. It should be strictly avoided during treatment to ensure safety and effectiveness of the medication. Inform patients that combining alcohol with antibiotics can lead to increased side effects or complications.

No Food with Certain Antibiotics (MTF)

• M: Macrolides (e.g., Azithromycin)

• T: Tetracyclines (e.g., Doxycycline)

• F: Fluoroquinolones (e.g., Levofloxacin)

• Guidance: These antibiotics should be taken on an empty stomach, ideally one hour before or two hours after meals, with water for optimal absorption. This maximizes therapeutic effect and minimizes gastrointestinal side effects.

Avoid Sun Exposure (FTS)

• F: Fluoroquinolones (e.g., Levofloxacin)

• T: Tetracyclines (e.g., Doxycycline)

• S: Sulfa drugs (e.g., Trimethoprim Sulfamethoxazole)

• Key points: Patients should be advised to practice sun safety due to the risk of photosensitivity reactions, which can lead to severe sunburns. The use of SPF 30+ sunblock is recommended, along with protective clothing and seeking shade during peak sunlight hours.

Monitor Toxicity with Myosin Antibiotics

• Myosins: This group includes Vancomycin, Gentamicin, and Neomycin, all of which have nephrotoxic and ototoxic potential.

• Importance of Monitoring Drug Levels: Regularly check the peak and trough levels of these medications to ensure they are within therapeutic ranges:

  • High levels: Indicate potential kidney damage, necessitating dose adjustments.

  • Low levels: Risk the possibility of treatment failure leading to infection resurgence.

• Symptoms of Toxicity: Educate patients about signs of toxicity:

  • Ototoxicity: Symptoms include tinnitus (ringing in the ears), vertigo, and loss of balance.

  • Nephrotoxicity: Look out for increased Blood Urea Nitrogen (BUN) and creatinine levels, along with significantly reduced urine output (less than 30 ml/hour), indicating kidney distress.

Broad Spectrum Antibiotics

• Penicillins (e.g., Amoxicillin, Ampicillin):

  • Mechanism: Weaken the bacterial cell wall, leading to bactericidal effects.

  • Notable for safety during pregnancy and breastfeeding but carry a risk of accidental pregnancy in women using hormonal contraceptives due to reduced efficacy.

• Cephalosporins (e.g., Cephalexin, Ceftriaxone):

  • Similar safety profile to penicillins; noted for a potential association with C. Diff infections.

  • Must check for allergies due to possible cross-sensitivity with penicillins, as severe allergic reactions (such as anaphylaxis) could occur.

Anaphylaxis vs. Redman Syndrome

• Anaphylaxis: Recognized through symptoms such as hives, angioedema (swelling of deeper layers of the skin), and wheezing; requires immediate cessation of medication and preparation of epinephrine for emergency response.

• Redman Syndrome: This occurs from a rapid infusion of Vancomycin; the recommended protocol is to infuse slowly (over at least 60 minutes) and closely monitor the patient’s blood pressure during administration to avoid hypotension.

Common Side Effects and Monitoring

• Cephalosporins: Diarrhea is particularly notable, as it can lead to dehydration; therefore, close monitoring is essential to manage any gastrointestinal disturbances.

• Penicillins: Regular checks of platelet counts are critical due to the risk of bleeding tendencies and should be done in high-risk patients.

• Myosins: Necessitates regular BUN and creatinine monitoring to catch any signs of nephrotoxicity early; vigilance for signs of toxicity (e.g., vertigo, tinnitus) is crucial.

Specific Antibiotics and Their Risks

• Macrolides (e.g., Azithromycin):

  • Risks include prolonged QT interval and hepatotoxicity, necessitating ECG monitoring and regular liver lab assessments to avoid serious cardiovascular and liver complications.

• Tetracyclines (e.g., Doxycycline):

  • Known for risks like tooth discoloration in children, as well as being deemed unsafe during pregnancy; can cross the placenta and affect fetal development. Avoid calcium and iron supplements, which can inhibit absorption, and instruct patients to maintain a sitting position for at least 30 minutes post-administration to prevent esophagitis.

• Metronidazole (Flagyl):

  • Commonly prescribed for C. Diff infections. Patients should avoid alcohol intake during treatment and for at least three days afterwards due to the risk of severe disulfiram-like reactions, which can cause flushing, palpitations, and nausea. Monitor closely for skin reactions such as Stevens-Johnson syndrome.

• Sulfonamide Antibiotics (Bactrim):

  • Mechanism involves inhibition of folic acid synthesis; key considerations include sun protection and adequate fluid intake to prevent crystalluria, along with monitoring for allergic reactions, especially in patients with a sulfa allergy.

• Fluoroquinolones (e.g., Levofloxacin):

  • Noteworthy risk of Achilles tendon rupture; educate patients on recognizing early signs and the importance of stopping the medication if they experience tendon pain. Unlike myosins, these are not nephrotoxic but do require monitoring of patient functional status.

• Phenazopyridine (Pyridium):

  • An analgesic used for urinary tract infections (UTIs); normalizes urine discoloration but necessitates advising patients to report any symptoms of liver toxicity promptly, including jaundice and unusual fatigue.

NCLEX Tips and Exam Questions

• Always assess patients for allergies before administering any medications, particularly antibiotics, as many severe reactions are noted during administering them.

• Familiarize yourself with symptoms associated with drug interactions and common side effects to effectively approach exam questions and improve patient safety in practice.

• Key takeaway: Always assess the patient's condition before contacting the healthcare provider or pharmacy with questions regarding prescriptions or allergy considerations to ensure the right treatment plan is in place.