Lysozyme: Indications, Dosage, Sore Throat Efficacy, and Side Effects

Nearly everyone "consumes" lysozyme every day—not through pharmaceuticals, but because human tears, saliva, and breast milk naturally contain this enzyme. But do lysozyme lozenges or capsules deliver meaningful anti-inflammatory effects? Is there scientific backing for using it to treat a sore throat? What is the correct dosage, and who should avoid it? Based on recent clinical literature from the National Library of Medicine (NIH/PubMed) and guidance from the Drug Office of Hong Kong, here is a complete medical overview.

What Is Lysozyme?

Lysozyme (also known as muramidase) is a naturally occurring antimicrobial enzyme in the human body. It was discovered in 1922 by British scientist Alexander Fleming in human nasal mucus; he observed that nasal secretions inhibited bacterial growth on agar plates and later identified lysozyme as the active constituent.

In humans, lysozyme is synthesized by immune cells (particularly phagocytes and mucosal epithelial cells) and is widely distributed throughout:

• Tears, saliva, and sweat
  
• Nasal secretions, urine, and breast milk
  
• Blood serum, liver tissue, and cartilage
  

Salivary lysozyme concentrations typically range from 2 to 60 µg/mL, serving as an essential first-line component of non-specific innate immunity.
Commercial pharmaceutical-grade lysozyme is purified predominantly from hen egg white, which represents the most abundant natural source of the enzyme. Common commercial brand names include Neo-Lysozyme, Leftose, and Likinozym. Formulations include oral tablets, capsules, throat lozenges, and oral sprays.

Mechanism of Action: Antibacterial and Anti-Inflammatory Effects

Lysozyme’s therapeutic utility stems from multiple distinct biological activities:

1. Antibacterial Mechanism (Direct Hydrolysis of Bacterial Cell Walls)

The classical mechanism of lysozyme involves enzymatic cleavage of the peptidoglycan backbone in bacterial cell walls:

• It specifically hydrolyzes the $\beta$-(1,4)-glycosidic bonds linking N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG).
  
• Once the peptidoglycan matrix degrades, the structural integrity of the cell wall fails, triggering osmotic imbalance and rapid bacteriolysis.
  

Lysozyme acts primarily against Gram-positive bacteria. It also exerts activity against select Gram-negative strains through non-enzymatic pathways (such as activating endogenous bacterial autolysins and disrupting cytoplasmic membranes).

Beyond its enzymatic antibacterial role, lysozyme exhibits:

• Antiviral activity against select viral pathogens (including HIV and herpesviruses like Herpes Simplex and Varicella-Zoster).
  
• Antifungal inhibitory activity against organisms such as Candida albicans.
  

2. Anti-Inflammatory Mechanism (Suppression of Pro-Inflammatory Mediators)

The anti-inflammatory property of lysozyme is a common clinical feature in the Hong Kong market. The underlying biological pathways include:

• Inhibition of TNF-$\alpha$ and IL-1$\beta$: In human monocyte models, lysozyme downregulates the transcriptional expression and secretion of pro-inflammatory cytokines TNF-$\alpha$ and IL-1$\beta$.
  
• Suppression of IL-6: In murine peritoneal macrophage assays, lysozyme inhibits lipopolysaccharide (LPS)-induced TNF-$\alpha$ and IL-6 release.
  
• Histamine Modulation: Lysozyme chloride suppresses mast cell histamine release, contributing to antiallergic and antiexudative responses.
  
• Tissue Repair: Neutralizes acidic metabolites generated during acute inflammatory processes, mitigates tissue edema, and accelerates mucosal re-epithelialization.
  

Key Distinction: Lysozyme is not a conventional anti-inflammatory drug in the pharmacological sense; it belongs neither to nonsteroidal anti-inflammatory drugs (NSAIDs) nor to corticosteroids. Its anti-inflammatory benefits are mediated through immunomodulation and the host immune clearance initiated upon bacterial cell wall breakdown—categorizing it as an adjunctive anti-inflammatory agent.

3. Immunomodulation

• A clinical trial in cancer patients undergoing chemotherapy demonstrated that lysozyme administration accelerated recovery of CD4+/CD8+ T-lymphocyte ratios, indicating positive immunomodulatory activity.
  
• As an innate immune effector, lysozyme bolsters local mucosal defense barriers, enhancing physiological resistance against upper respiratory tract pathogens.
  

Clinical Indications for Lysozyme

Clinical reference materials from OT&P Healthcare, Bowtie Health, and Vinmec indicate that lysozyme is commonly utilized for:

• Upper respiratory tract inflammation: Acute pharyngitis, tonsillitis, laryngitis, and sore throat relief.
  
• Oral and dental conditions: Aphthous ulcers (canker sores), gingivitis, periodontitis, and post-dental extraction swelling.
  
• Respiratory mucus clearance: Adjunctive mucolysis in acute/chronic bronchitis and bronchiectasis (often compounded with mucolytics).
  
• Dermatological and surgical conditions: Minor wound management and localized edema control.
  

Clinical Evidence for Sore Throat

Study 1: Infectious Tonsillopharyngitis (Large-Scale Study of 1,727 Patients)

A study published in Materia Socio-Medica (indexed in NIH/PMC) assessed 1,727 patients with acute tonsillopharyngitis (predominantly viral) treated with an oral spray formulation (Lysobact Spray) combining lysozyme chloride and cetylpyridinium chloride over 5 days:

• 95% of patients evaluated the therapeutic effect as effective or highly effective.
  
• 32% of participants reported measurable symptomatic relief within 10 minutes of initial application.
  
• 74.11% demonstrated complete resolution of sore throat symptoms with good therapeutic response.
  
• Adverse event rates were minimal at 0.004% (7 patients reported mild side effects: 3 cases of rash, and 1 case each of dysgeusia, xerostomia, and oral burning sensation).
  
• 97% of patients reported good to excellent tolerance.
  

Study 2: Non-Infectious Sore Throat (Occupational Cohort of Teachers)

A pilot clinical study published in the Bosnian Journal of Basic Medical Sciences (indexed in NIH/PMC) evaluated 25 schoolteachers—an occupational group prone to non-infectious vocal strain and pharyngitis—using lysozyme lozenges 6 times daily for 5 days:

• Lysozyme lozenges delivered positive relief from non-infectious sore throat discomfort.
  
• Zero adverse events were observed throughout the study duration.
  
• 92% of participants reported that they would select the same treatment for future episodes.
  

Scientific Caveat: Available clinical trials evaluating lysozyme for sore throat generally feature small sample sizes (such as the 25-patient pilot study), and several received pharmaceutical industry funding. While these represent valid proof-of-concept findings, robust confirmation requires larger, randomized, double-blind, placebo-controlled trials (RCTs).

Recommended Dosage and Administration

Clinical dosing guidelines compiled by OT&P Healthcare and Bowtie include:

Oral Tablets / Capsules (Most Common Dosage Form)

• Standard Adult Dosage: 90 mg to 270 mg daily, divided into 2 to 3 equal doses (typically 1 tablet/capsule of 30 mg to 90 mg three times daily).
  
• Pediatric Dosage: Must be determined by a physician based on body weight (often 30 mg to 60 mg two to three times daily for older children).
  

Administration Guidelines:

• May be taken before or after meals.
  
• Swallow whole: Do not crush, grind, or chew tablets or capsules; altering the dosage form may accelerate systemic absorption and increase localized gastrointestinal irritation.
  
• Consult a physician or pharmacist prior to administration if unclear.
  

Lozenges / Oral Sprays

• Lozenges: Regimens referenced in clinical literature evaluate 1 lozenge slowly dissolved in the mouth up to 6 times daily for 5 days.
  
• Oral Spray: Administer per package instructions, typically 1 to 2 sprays every 2 to 3 hours as needed.
  
• Symptomatic improvement—particularly sore throat easing—is often observed within minutes of local lozenge or spray application.
  

Availability in Hong Kong

In Hong Kong, lysozyme products are categorized as over-the-counter (OTC) formulations and do not require a doctor's prescription. They are available at retail chains such as Watsons and Mannings, as well as community pharmacies. Records from the Drug Office of the Department of Health show over 250 registered pharmaceutical products containing lysozyme.

Adverse Effects: Common and Rare

Lysozyme demonstrates an established safety profile; the US Food and Drug Administration (FDA) categorizes it as Generally Recognized As Safe (GRAS) for designated food applications. However, potential adverse effects include:

• Gastrointestinal: Nausea, vomiting, dyspepsia, mild anorexia, abdominal discomfort, and diarrhea.
  
• Dermatological: Generalized pruritus, mild skin flushing, and erythema.
  

Warning: Severe Egg Allergy Risks

The Drug Office of the Department of Health in Hong Kong has relayed medical alerts issued by Singapore's Health Sciences Authority (HSA):

Because commercial lysozyme is purified from hen egg whites, it can precipitate severe allergic reactions in individuals with hypersensitivity to egg proteins.

Documented adverse drug reaction (ADR) reports highlight a child with known egg allergy who developed acute paroxysmal coughing, generalized urticaria, and an acute exacerbation of eczema after ingesting lysozyme. Additional reported ADRs include periorbital edema and systemic erythematous rashes.

Healthcare providers should verify an individual's personal history of egg allergies prior to recommending or dispensing lysozyme.

Contraindications and Populations Who Should Avoid Lysozyme

Lysozyme vs. Conventional Anti-Inflammatory / Analgesic Agents

Primary References and Official Health Sources

1. NIH/PubMed — Lysozyme in Non-Infectious Sore Throat: A Pilot Study (Bosnian Journal of Basic Medical Sciences, 2020/2022):
   https://pmc.ncbi.nlm.nih.gov/articles/PMC7202184/
   https://pubmed.ncbi.nlm.nih.gov/35695397/
   
2. NIH/PubMed — Efficacy and Safety of Lysozyme-Containing Oral Spray (1,727 Cases, Materia Socio-Medica, 2016):
   https://pmc.ncbi.nlm.nih.gov/articles/PMC5239661/
   
3. NIH/PMC — Therapeutic Applications and Bioactive Properties of Lysozyme (Frontiers in Pharmacology, 2021):
   https://pmc.ncbi.nlm.nih.gov/articles/PMC9982862/
   
4. OT&P Healthcare Hong Kong — Lysozyme Drug Information (Dosing, Side Effects, and Warnings):
   https://www.otandp.com/medicines-in-hong-kong/lysozyme
   
5. Drug Office, Department of Health (Hong Kong) — Safety Precautions on Lysozyme-Containing Medicines in Egg-Allergic Patients:
   https://www.drugoffice.gov.hk
   
6. Vinmec International Hospital — Lysozyme Chloride: Uses, Administration, and Dosages:
   https://www.vinmec.com/eng/blog/what-is-lysozyme-chloride-uses-and-dosages-en
   
7. Bowtie Health Blog — Lysozyme Guide: Uses, Side Effects, and Over-the-Counter Guidance:
   https://www.bowtie.com.hk/blog/en/drugs/lysozyme/
   

(Disclaimer: The medical information provided above is intended for general health education and informational purposes only and does not constitute individual medical advice, clinical diagnosis, or a treatment plan. Always consult a registered medical practitioner or licensed pharmacist regarding any persistent symptoms or medication regimens.)