Drug Interactions with Azithromycin in Dogs & Cats (Respiratory Infections)

 

Drug Interactions with Azithromycin in Dogs & Cats (Respiratory Infections)

✅ Synergistic

  • Azithromycin + Beta‑lactams (e.g., amoxicillin)
    Combining a bacteriostatic macrolide with a bactericidal beta‑lactam provides complementary mechanisms of action and broader bacterial coverage, making this combination synergistic in mixed respiratory infections. [msdvetmanual.com]
  • Azithromycin + Atovaquone (in dogs/cats for Babesia)
    These drugs are frequently used together, especially in canine babesiosis, due to complementary effects targeting different pathogen stages. [wedgewood.com], [veterinary...er.vin.com]

➕ Additive

  • QT‑prolonging agents (fluoroquinolones like enrofloxacin/pradofloxacin, antiarrhythmics such as sotalol, ondansetron)
    Concurrent use with azithromycin increases the risk of QT prolongation, leading to additive cardiac effects. [marvistavet.com], [wedgewood.com], [merckvetmanual.com]
  • NSAIDs
    Co-administration (e.g., with carprofen, meloxicam) may increase GI irritation or ulceration; additive in causing digestive adverse effects. [petmd.com], [vin.com]

❌ Antagonistic

  • Antacids / sucralfate
    Aluminum or magnesium-containing antacids bind azithromycin in the gut, significantly reducing its absorption and effectiveness. [vin.com], [bing.com]
  • Other bacteriostatic protein synthesis inhibitors (e.g., clindamycin)
    Co-administering two bacteriostatic antibiotics may reduce bacterial kill rates, potentially causing antagonistic effects. [msdvetmanual.com]

📝 Summary

While azithromycin pairs well with beta-lactams or atovaquone (synergy), caution is needed when combining it with QT‑prolonging drugs (fluoroquinolones, antiarrhythmics), NSAIDs, and antacids. Avoid combinations that reduce absorption or increase adverse effects, and monitor cardiac and gastrointestinal function closely during co-administration.


🐱 Azithromycin Dosing for Feline Respiratory Infection

Standard Oral Dosing

Mycoplasma-associated Infections

  • 5–15 mg/kg orally once daily for 5 days, followed by every 72 hours for 6–8 weeks is recommended for infections linked to Mycoplasma spp.. [ohiostate....sbooks.pub]

Extended Treatment Approach

  • Some protocols begin with 5–10 mg/kg daily for 5 days, then switch to 5–10 mg/kg every 3 days to clear persistent or chronic respiratory infections. [petshun.com]

📋 Example Posology for a 4 kg Cat

Day RangeDoseFrequencyNotes
Days 1–520–40 mg/dayOne dose dailyTypical acute-phase treatment
Days 6–42 (if needed)20–60 mgEvery 72 hours (q3d)Especially for Mycoplasma infections

Veterinary Prescription Abbreviations and Meanings

AbbreviationLatin TermMeaning
SIDsemel in dieOnce daily
QDquaque dieOnce a day
ODomni dieOnce daily (less common)
BIDbis in dieTwice daily
TIDter in dieThree times daily
QIDquater in dieFour times daily
q12h—Every 12 hours
q8h—Every 8 hours
q24h—Every 24 hours
q72h—Every 72 hours
PRNpro re nataAs needed
statstatimImmediately
ad libad libitumAs desired (free choice)
POper osBy mouth
SC / SQ—Subcutaneous
IM—Intramuscular
IV—Intravenous
ID—Intradermal

Comments

Post a Comment

Popular posts from this blog

  For bacteriology testing aimed at identifying and conducting Antimicrobial Susceptibility Testing (AST) for GLASS (Global Antimicrobial Resistance Surveillance System) priority pathogens , various reagents and supplies are typically required. Here's a list of essential reagents for such testing: 1. Culture Media: Nutrient Agar : For general cultivation of bacteria. Blood Agar : For growing fastidious organisms and detecting hemolytic activity. MacConkey Agar : For selective isolation of Gram-negative bacteria, particularly Enterobacteriaceae. Mannitol Salt Agar : For the selective isolation of Staphylococcus aureus . Chocolate Agar : Enriched medium for fastidious organisms like Haemophilus and Neisseria species. Cetrimide Agar : For selective isolation of Pseudomonas aeruginosa . XLD Agar (Xylose Lysine Deoxycholate) : For selective isolation of Salmonella and Shigella . 2. Gram Staining Reagents: ...
Read more

Citrobacter freundii

Image
1. What is Citrobacter freundii? Citrobacter freundii  is a species of facultative anaerobic Gram-negative bacteria belonging to the family Enterobacteriaceae. It is rod-shaped and typically measures 1-5 μm in length.  This bacterium is commonly found in soil, water, sewage, food, and the intestinal tracts of animals and humans 1 2 . 2. Transmission of Citrobacter freundii Citrobacter freundii  can be transmitted through: Direct contact : With contaminated surfaces or materials. Ingestion : Of contaminated food or water. Nosocomial transmission : In healthcare settings, particularly affecting immunocompromised patients 2 . 3. Epidemiology of Citrobacter freundii Citrobacter freundii  is widely distributed in the environment and is a common component of the gut flora.  It is considered an opportunistic pathogen, primarily causing infections in immunocompromised individuals, the elderly, and those with prolonged hospital stay...
Read more

Spearman's Rank Correlation Coefficient (ρ)

Image
 Spearman's Rank Correlation Coefficient (ρ) Definition: Spearmans' rank correlation coefficient is a non-parametric measure of the correlation between two variables that examines the relationship between their rankings, rather than their actual values. Formula: $$ρ = \frac{\sum{i=1}^{n} (ri - si)^2}{\sum{i=1}^{n} (ri^2 + si^2 - 1)}$$ where:  n is the number of paired observations  ri is the rank of the i-th observation in the first variable  si is the rank of the i-th observation in the second variable Interpretation:  -1 ≤ ρ ≤ 1  ρ = 1: Perfect positive correlation (rankings of both variables are exactly the same)  ρ = -1: Perfect negative correlation (rankings of the variables are exactly opposite)  ρ = 0: No correlation (no relationship between the rankings) Assumptions:  The data should be ordinal, i.e., their values represent ranks or positions.  The relationship between the variables should be monotonic, i.e., as one variable incr...
Read more