azithromycin and benzalkonium chloride

Action and Spectrum

Actions and spectrum: 

azithromycin: 

• Action: azithromycin is an antibiotic belonging to the macrolide class. It works by inhibiting bacterial protein synthesis. Specifically, it binds to the 50S subunit of the bacterial ribosome, preventing the formation of new proteins essential for bacterial growth and reproduction. This action leads to the inhibition of bacterial growth and the death of susceptible bacteria. 
• Spectrum: azithromycin has a broad spectrum of activity against many Gram-positive and Gram-negative bacteria. It is used to treat skin & soft tissue infections, respiratory tract infections, sexually transmitted infections, and other bacterial infections. 

benzalkonium chloride: 

• Action: benzalkonium chloride (BZK) is a quaternary ammonium compound with antimicrobial properties. It acts as a disinfectant and antiseptic agent. BZK disrupts the cell membranes of microorganisms, including bacteria and viruses, leading to the leakage of cellular contents and cell death. It is commonly used in various topical antiseptic and disinfectant products. 
• Spectrum: benzalkonium chloride has a broad spectrum of antimicrobial activity against bacteria, viruses, and fungi. It is often used in products such as hand sanitizers, wound cleansers, and disinfectant sprays to reduce the risk of infection. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Nausea 

Diarrhoea 

Angioedema 

Urticaria 

Dizziness 

Cholestatic jaundice 

Vertigo 

Chills 

Lightheadedness

Vaginal dryness 

Confusion 

Muscle aches 

Black Box Warning

Black Box Warning: 

There is no specific black box warning associated with azithromycin and benzalkonium chloride. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

• Allergy or Hypersensitivity: Contraindicated in individuals with known hypersensitivity or allergic reactions to azithromycin and benzalkonium chloride. 
• Liver Disease: Caution is advised, and dose adjustments may be necessary when using azithromycin in individuals with severe liver disease. benzalkonium chloride is typically used topically and may not pose significant concerns in this context. 
• Kidney Disease: Individuals with severe kidney disease may require dose adjustments when taking azithromycin. Use of azithromycin should be carefully monitored in these cases. 
• Medication Interactions: azithromycin may interact with certain medications, including antacids and other drugs that can affect its absorption. Check with a healthcare provider for potential drug interactions.

Caution: 

• Resistance: Overuse or inappropriate use of antibiotics like azithromycin can contribute to antibiotic resistance, which makes infections more difficult to treat in the future. Use antibiotics only when prescribed by a healthcare provider for bacterial infections. 
• Age and Pediatric Use: azithromycin should be used with caution in newborns and infants, particularly those born prematurely, as it may cause a specific heart rhythm problem known as prolongation of the QT interval. The use of benzalkonium chloride may vary depending on the specific product and age of the individual. 
• Topical Application If benzalkonium chloride is used in topical formulations, avoid contact with eyes, mucous membranes, and open wounds, as it can cause irritation.

Comorbidities: 

• Cardiovascular Conditions: Patients with a history of heart disease, arrhythmias, or other cardiovascular conditions should use azithromycin with caution, as it may prolong QT interval, which can increase the risk of arrhythmias.  
• Respiratory Conditions: Patients with COPD, asthma, or bronchiectasis may benefit from azithromycin for its anti-inflammatory properties. However, it should be used under the guidance of a healthcare provider to assess potential benefits and risks. 
• Immunosuppression: Individuals with HIV/AIDS or undergoing immunosuppressive therapy, may be more susceptible to infections. The use of antibiotics like azithromycin should be carefully considered and monitored in these cases. 
• Eye Conditions: If benzalkonium chloride is used in ophthalmic solutions, individuals with certain eye conditions or sensitivities should be cautious and consult with an eye specialist. 

Pregnancy / Lactation

Pregnancy consideration: pregnancy category: not assigned 

Lactation: excreted into human milk: unknown  

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• <b>Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

The combination of azithromycin and benzalkonium chloride represents two distinct pharmacological components with different mechanisms of action. azithromycin is a macrolide antibiotic that inhibits protein synthesis, effectively targeting and eradicating susceptible bacteria. It is used to treat bacterial infections.

On the other hand, benzalkonium chloride is a quaternary compound with antiseptic & disinfectant properties. It disrupts the cell membranes of microorganisms, rendering them nonviable. This combination is not typically used together but rather for different purposes: azithromycin for bacterial infections, and benzalkonium chloride as a topical antiseptic and disinfectant.  

Pharmacodynamics: 

• Inhibition of Protein Synthesis: azithromycin binds to the 50S subunit of bacterial ribosomes, preventing the elongation of the polypeptide chain during protein synthesis. This action disrupts bacterial cell growth and reproduction, leading to cell death. 
• Bacteriostatic and Bactericidal Effects: azithromycin can exhibit both bacteriostatic and bactericidal effects, depending on the concentration and susceptibility of the target bacteria. 
• Broad-Spectrum Antimicrobial Activity: benzalkonium chloride exhibits broad-spectrum antimicrobial activity against bacteria, viruses, and fungi. 
• Antiseptic and Disinfectant Uses: It is commonly used in topical antiseptic solutions and disinfectant products to reduce the risk of infection in wounds, on skin, and on surfaces.

Pharmacokinetics: 

azithromycin: 

• Absorption: azithromycin is orally administered and is well-absorbed from the gastrointestinal tract. It is available in various formulations, including tablets and oral suspensions. Food can affect its absorption, with higher bioavailability when taken with food. 
• Distribution: azithromycin is distributed throughout the body, including in tissues and cells. It has a long half-life, allowing for once-daily dosing. The drug can penetrate respiratory tissues, making it effective for treating respiratory infections. 
• Metabolism: azithromycin undergoes minimal metabolism in the liver. The drug gets eliminated unchanged in the bile and then excreted in the feces. 
• Excretion: A small portion of azithromycin is excreted in the urine, but the primary route of elimination is through bile and feces. This property contributes to its long half-life. 

benzalkonium chloride: 

• Absorption: When benzalkonium chloride is used topically, it is not significantly absorbed into the bloodstream through intact skin or mucous membranes. However, absorption can occur if applied to damaged or compromised skin. 
• Distribution: In cases where absorption occurs, benzalkonium chloride can be distributed throughout the body. 
• Metabolism: benzalkonium chloride is not metabolized by the body. 
• Excretion: Excretion of benzalkonium chloride primarily occurs through urine or feces, depending on the route of absorption. 

Adminstartion

Administration: 

• Oral Tablets/Capsules: These are typically taken by mouth with a full glass of water. azithromycin may be taken with or without food, but it is important to follow the specific instructions provided with your medication. 
• Intravenous (IV) Solution: In some cases, azithromycin may be administered intravenously in a healthcare setting by a healthcare professional. 
• Topical Solutions/Wipes: benzalkonium chloride is often found in antiseptic solutions, wipes, and hand sanitizers. When using these products, follow the instructions on the product label. Typically, you would apply the solution to the affected area (e.g., skin or surface) and allow it to dry. 
• Ophthalmic Products: Some ophthalmic (eye) solutions contain benzalkonium chloride as a preservative. These should be used as directed by your eye care professional. Avoid touching the eye dropper tip to prevent contamination. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: azithromycin and benzalkonium chloride 

Pronounced: (ah-ZITH-roh-MY-sin-and- BEN-zal-KO-nee-um KLOR-ide)  

Why do we use azithromycin and benzalkonium chloride? 

Azithromycin is commonly used to treat bacterial infections, including bronchitis & pneumonia, skin & soft tissue infections, sexually transmitted infections, and others. It is an antibiotic that works by inhibiting bacterial protein synthesis.

benzalkonium chloride is often used in various topical antiseptic products, including hand sanitizers, wound cleansers, and surface disinfectants. It is used to reduce the risk of infection by inhibiting the growth of bacteria, viruses, and fungi on the skin or surfaces.